Subsidy Project of Decommissioning and Contaminated Water
Management for FY2021
Development of Fuel Debris Retrieval Method

FY2022 Final Report

June 2023
International Research Institute for Nuclear
Decommissioning (IRID)
All rights reserved.
©International Research Institute for Nuclear Decommissioning (IRID)

No.1

Table of Contents
Purpose and Goals of “Development of Fuel Debris Retrieval Method”
Accomplishments of Related Projects Implemented in FY2019-20
Project Overview
Implementation Schedule
Project Organization
Implementation Items of This Project1) Development of side access method
2) Development of top access method
7. Summary
8. Specific Goals for Achieving the Purpose of the Project and Evaluation of
Level of Achievement
1.
2.
3.
4.
5.
6.

©International Research Institute for Nuclear Decommissioning1. Purpose and Goals of “Development of Fuel Debris Retrieval Method”

No.2[Purpose of development of fuel debris retrieval method]
It is believed that the nuclear fuel has melted along with the core internals at Tokyo Electric Power Company Holdings, Inc. (TEPCO) Fukushima Daiichi
Nuclear Power Station (1F) and exists in the Reactor Pressure Vessel (RPV) and the Primary Containment Vessel (PCV) as fuel debris.
Although it is believed that the fuel debris present inside the RPV and PCV is currently in a sub-critical state, since the Reactor Building (R/B), RPV, PCV,etc. have been damaged due to the accident, the plant itself is in an unstable condition unlike its initial design. In order to prevent diffusion of radioactive
materials and bring the fuel debris to a stable condition, the fuel debris needs to be retrieved and its sub-critical state needs to be maintained.
Against this background, we will conduct studies in this project based on the “Mid-and-long-term Road-map Towards Decommissioning of Tokyo ElectricPower Company Holdings, Inc.’s Fukushima Daiichi Nuclear Power Station” (hereinafter “Mid-and-Long-Term Road-map”), aiming towards theimplementation of work for further increasing the scale of fuel debris retrieval in coordination with the engineering and project management activities
undertaken by Tokyo Electric Power Company Holdings, Inc. (TEPCO). The development results of this project will be used in TEPCO’s engineering
activities.
The purpose of this project is to smoothly carry out decommissioning and contaminated water management at 1F by implementing projects that support
technological development contributing to the decommissioning and contaminated water management at 1F based on the Mid-and-Long-Term Road-map
and the “FY2021 Decommissioning Research & Development Plan” (Secretariat Meeting of the Team for Countermeasures for Decommissioning andContaminated Water Treatment (86th), and in addition, to make efforts to enhance the standard of science and technology in Japan.
Under the project for “Development of Fuel Debris Retrieval Method”, the elemental technologies required for securing retrieval work area for thetechnologies related to equipment, devices and systems required for increasing the retrieval scale of fuel debris and reactor internal structures, and for
ensuring throughput, will be developed and tested based on research and development results obtained so far.

[Project goal]
The goal of the project is to conduct studies in order to accomplish work for further increasing the scale offuel debris retrieval based on the Mid-and-Long Term Road-map.

[Duration of Project] April 2021 to March 2023 (2 years)©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.3

The fuel debris retrieval method results related to this project are provided below.
Details pertaining to (1) to (5) are provided in the following pages.
(1) Establishment of access route for installation of cells(4) Access equipment(2) Access tunnelInterfering objects

Distal end of the rail israised due to the inclination,and hence vertical space isrequired.

Robot arm

Welding
robot

Unit canLine of flow of the robot
arm and unit can
Height is reduced bykeeping the rail inside
the cell horizontally

Welding head

Access rail

Fixed rail

Robot arm

Welding
robot
Frame

Simulated equipment
hatch part

Robot arm
Transportat
Line of flow of the robot
ion cart
arm and unit can

Dual arm typemanipulator

Frame

Result: Development of access tunnel
installation (welding) technology

Result: Development oftechniques for supporting
remote operations

Unit canResult: Developmentof access routeestablishment
technology related to
installation of the cells(3) Side access method using access tunnel
CRD
opening

Interference
removalequipment

CRD
opening

Interfering
objects(5) Top access method
Secondary boundary
Retrievalequipment
Additional building

Passageway

Connection
sleeveInterfering
objects
Processing
tool

Dual lid
Transportation
cart

Dedicated transport
container

Processing tool

Result: Method for interference removalusing fuel debris retrieval equipment
when side access method

Result: Development of technology for removing
interfering objects and reactor bottom©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.4(1) Establishment of access route for installation of cells[Overview of access route establishment for installation of the cells]•••

A boundary is set up by means of cells and fuel debris is retrievedby accessing from the side of the PCV using a robot arm.
Considering accessibility of the pedestal opening, the robot arm iscarried in via the shortest linear route to access fuel debris.
The cells are installed after reducing the load on the R/B floor
because they are heavy.

Fuel debris
retrieval cell

Mini cask cell

Transportation
cask cell
Canister cell

Fuel debris
retrieval
preparatory cell
Dual arm type robot
container[Items implemented until FY2020]① Access equipment•
The access equipment was modified from using the access rail method tofixed rail method, the required height and space were reduced, andconceptual study was completed.
② Cell (Fuel debris retrieval cell established inside the R/B)•
The functions of the fuel debris retrieval cell were clearly specified, theequipment inside the cell were studied, the cell structure was substantiatedand its size was reduced.
•
The shielding thickness was streamlined to reduce the weight of the fueldebris retrieval cell.
•
The method of installing the cell installation frame on the wall and floor beams,
which are the strong members of the building, to support the weight of the cell
was studied, and it was confirmed that the installation in that manner ispossible from the perspective of allowable load at each R/B location.
③ Study of cell installation method•
The illustration showing the steps that are expected to be viable frompreparatory works to installation was studied and technical issues wereidentified.

Fuel debris transportation
cask cell

Transportation cask yard

Access equipment
Temporary storage area
Maintenance cell
Equipment transfer container

Equipment transfer
container yard

Reactor building
Floor beam

Installation cell frame

BSW
Fuel debris retrieval cell

Reactor building wall

©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.5(1) Establishment of access route for installation of cells◼ Issues in cell installation: Issues related to this project are excerpted from the Fuel Debris Retrieval FY2020 Final
Report*1
No.

Issue

1

Detailing of the structure of the shielding door andthe structure between cells

2

Substantiation of the cell adapter structure3

Substantiation of the method of carrying-in andinstalling the shielding door and the cell adapter

4

Establishment of the reference marking method
for cell installation

Overview

This project

The partitioning structure of the shielding door for substantiating
an efficient installation method so as to reduce the exposure ofworkers, and the structure of the connecting part between thecells will be detailed.

Refer to 6.1) (1) ①

The structure of the cell adapter required for adopting themethod of installing the cell adapter by remote operation will be
substantiated.

Refer to 6.1) (1) ①

The steps involved in carrying-in and installation will be detailed,based on the detailed structures of the shielding door, cell
adapter and cell; element tests pertaining to the method of
installation by remote operation will be planned andimplemented; and feasibility will be verified.

Refer to 6.1) (1) ①

The method of measurement and marking performed inadvance for determining the reference line from the pedestal
opening or X-6 penetration, etc. required for installing the cell
will be established.

Refer to 6.1) (1) ①*1： “Development of Technology for Further Increasing the Scale of Retrieval of Fuel Debris and Reactor Internal Structures” FY2020 Final Report (March 2021)©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20(2) Access tunnel

Additional

増設建屋
building[Overview of access tunnel]•••

The additional building outside the R/B and the PCV is connected with anaccess tunnel having a shielding function, to establish the carrying-in/out
route.
The load of the access tunnel will be borne by the outer wall of the R/B
and the Biological Shield Wall (BSW), in order to maintain within the load
limit for the floor surface on the first floor.
The tunnel is assembled outside the R/B, and is inserted and installed byremote operation so as to reduce worker exposure.

[Items implemented until FY2020]
•

•

PCV
Access tunnel
アクセストンネル

The work procedures from removing the shield in front of the equipment
hatch to connecting the access tunnel to the PCV were drafted taking
remote operation into consideration, and the exposure dose in the eventof operations that are not carried out remotely was estimated.
The structure of the connecting part between the PCV and sleeve, andthe sleeve and access tunnel was studied, element tests related toconnecting the PCV (equipment hatch) and the sleeve by means of
welding were conducted, and it was verified that the 20mm gap can bewelded.

Testing by setting conditions
Gap

Flat plate(t=12)

Flat plate(t=90)

No.6✓ Stacking
method✓ Weldingposition✓ Heat input for
welding✓ Welding gap

Overview of access tunnel

Element test
✓ Welding gap(Equipment similar
to the actual facility)<While creating the arc>

Implemented<Welding machine>

Welding test being conducted©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.7(2) Access tunnel◼ Issues in the whole access tunnel: Items related to this project are excerpted from the Fuel Debris
Retrieval FY2020 Final Report*1
No.

1

2

3

Issue

Overview

This project

Installation accuracy of access tunnel
sleeve

The access tunnel sleeve is welded to the PCV
equipment hatch shell. Although it was confirmedthat the 20mm gap can be welded, the gap
needs to be reduced as much as possible
considering the on-site workability, thermal
contraction effect at the time of welding, andquality.

Refer to 6.1) (1) ②

Reduction in the scale of delivery
equipment by reducing the delivery
weight of the main body of the accesstunnel and shortening of theinstallation process

The delivery weight of the main body of theaccess tunnel is approx. 430 ton, and exceeds
1000 ton if the counterweight is included. Hence,the delivery equipment and the related provisions
outside the R/B are large scale. This leads toissues such as not being able to start
preparations around the R/B such as
constructing the additional building, etc.

Refer to 6.1) (1) ③

Shield block (Unit 1) and BSW blockout (Units 2, 3)(Unit 1) After pulling out the existing shield plug,
as it interferes with the access tunnel main body,it needs to be removed.
(Units 2, 3) BSW needs to be blocked out.

Refer to 6.1) (1) ④*1： “Development of Technology for Further Increasing the Scale of Retrieval of Fuel Debris and Reactor Internal Structures” FY2020 Final Report (March 2021)©International Research Institute for Nuclear Decommissioning

No.8

2. Accomplishments of Related Projects Implemented in FY2019-20(3) Side access method using access tunnel

Carrying-in
搬入セルcell

廃棄物
Waste
搬出セル
transfercell[Overview of side access method using access tunnel]✓✓✓

The PCV and additional building are connected by means of a passage(access tunnel). The access tunnel is installed by delivering it remotelyfrom outside the R/B.
The work of removing interferences from inside PCV and the work offuel debris retrieval is carried out using multiple equipment for remote
operation. Equipment is assembled inside PCV as required.
This method is applicable regardless of the unit and whether theinterference is inside or outside the pedestal.

Maintenance
保守セル cell

PCV
燃料デブリ
Fuel
debristransfercell
搬出セル
Passage (access tunnel)
通路(アクセストンネル)

Illustration showing how the PCV and additionalbuilding are connected[Items implemented until FY2020]✓✓✓

The feasibility of the work of installing common utilities(assembling the stand, connecting the utility line) was verified.
It was projected that comparatively smaller interfering objects
such as fallen ICM (In-core monitor) housing can be removed byremote operation.
It was projected that the work of routing cables, processing fueldebris, etc. can be carried out in parallel using multiple equipment
Connection of the cables ofユーティリティラインとPCV内でのthework equipment inside
作業装置のケーブルを接続
the
PCV to the utility line

Equipment
機器ハッチ
hatch

Utility line: Installed
ユーティリティライン：by遠隔にて構築
remote operation

Simulated
ICM
housingIllustration showing
installation of utility line

CRD opening
CRD開口
(Only
base minimum equipment for※CRD開口に常設になるのは最低限のcarrying-in/out
and cables are
搬出入設備とケーブルのみ
permanently
installed at the CRD
opening.)

1. Carrying-in the①干渉物撤去interference removal
装置搬入
equipment
2. Carrying-in the②CRD開口周辺
interference removal
干渉物撤去
equipment

5. Transfer of⑤干渉物の搬出interfering
objects

Illustration showing removal ofinterfering
objects from around the
CRD開口周辺干渉物撤去イメージ
CRD opening
Interference removal
干渉物撤去装置
equipment

3.③ペデスタル
Accessing thepedestalbottom
底部アクセス
4. Removal of interfering objects④ペデスタル底部干渉物撤去
from the pedestal bottom

Saber saw
Monitoring
監視装置
equipment

Fuel debris
燃料デブリ
retrieval cell
取り出しセルWork arm

Cutting jig

Illustration showing work inside the pedestal

Cutting of simulated ICM housing©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.9(3) Side access method using access tunnel◼ Issues in side access method: Items related to this project are excerpted from the Fuel Debris Retrieval
FY2020 Final Report*1

No.

1

Issue

Method of removing large
interfering objects

Overview

This project

The method of removing large
interfering objects such as CRD
changer, which cause major hindrance
in the fuel debris retrieval work, by
remote operation, will be studied.

Refer to 6.1) (2)① to ③*1： “Development of Technology for Further Increasing the Scale of Retrieval of Fuel Debris and Reactor Internal Structures” FY2020 Final Report (March 2021)©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.10(4) Access equipment[Overview of access equipment]•

The access equipment is carried-in in a straight line towards the pedestal opening in the PCV, and the interfering
objects on the access route and fuel debris inside the pedestal are cut and collected.

Telescopic interference
removal equipment（Dual motor-operated arms)

Fixed rail type dual motoroperated arms

[Items implemented until FY2020]•

Fixed rail type hydraulicarms
Trajectory for avoiding simulated interfering objects
and reaching the target value
Trajectory ofTrajectory of
the left arm
the right arm

The following conceptual studies on the access equipment for accessing the interfering objects and fueldebris were completed.
➢

Concept, structure and installation method of the fixed rail and telescopic guiding equipment.

➢

Concept, structure, method of carrying-in, method of emergency withdrawal of the dual motoroperated arms.

➢

Method of using the hydraulic arms with the fixed rail.

•

The height of the access equipment was reduced from 3m to 2.2m.

•

It was confirmed that the load of the access equipment does not cause any issues in the integrity of thepedestal CRD opening.

•

The procedures for removing the interfering objects and retrieving fuel debris were brushed up andsubstantiated, technical issues were identified and the actions to be taken in response were studied.

•

Methods supporting remote operation were studied for better work efficiency.

Generation of trajectory when
methods supporting remote
operation are adopted©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.11(4) Access equipment◼

Issues in the access equipment: Items related to this project are excerpted from the Fuel Debris Retrieval FY2020 Final Report*1

No.

Issue

Overview

This project

Conceptual study of tip tool

The method for cutting the assumed interfering objects
and fuel debris and the concept of the tip tool need to bestudied although under certain pre-conditions to get an
idea of the overall work including throughput.

Refer to 6.1) (3) ①

2

Dealing with deviations

Deviations during remote operation support by the
manipulator, caused due to the difference in the 3Dmodel and the actual objects on-site, and due to errors ininstallation by using the robot, need to be dealt with.

Refer to 6.1) (3) ①

3Establishment of remote
operation support required
during the operation

Remote operation support needs to be established for
operations such as cutting, grabbing and collection.

Refer to 6.1) (3) ①

1*1： “Development of Technology for Further Increasing the Scale of Retrieval of Fuel Debris and Reactor Internal Structures” FY2020 Final Report (March 2021)©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.12(5) Top access method[Concept of the new top access method (removing and transferring unitized structures)]✓✓✓✓

Individual structures are unitized and transferred
The reactor core is cut into multiple units, and the lower hemispherical dome at the reactor bottom is separated from the RPV asa single unit.
The shielding and air tightness of the objects to be transferred is ensured by using dedicated transportation containers fortransporting structures or access route or a combination of both.
The work of finely cutting the structures that are retrieved and enclosing them in storage containers is carried out in a buildingthat is at a distance from the R/B.

[Items implemented until FY2020]✓✓✓

The retrieval plan and removal method pertaining tointerfering objects, from removing the shield plug up to thereactor bottom, were consolidated and a draft of the steps
involved in the access method was created.
It was indicated that measures to reduce the weight of theshielding on the operation floor, the crane and the meansof transportation are feasible, and the specifications suchas dimensions, shield weight, etc. of the largetransportation container were created.
Element tests were conducted pertaining to the reactor
bottom part which is difficult to access due to spaceconstraints and for which the work procedures such as forfall prevention measures, etc. are complex, and therequired time obtained from test results was reflected in
the throughput estimation.

原子炉建屋
Reactor Building
Crane
揚重機

Additional

Retrievalequipment
取り出し装置増設建屋
building

Transportation
搬送
cart
台車

Dual lid
二重蓋

連絡通路
Passageway
Heavy
weightオペフロ上
on the
重量大 floor
operation

Connection
接続
sleeve
スリーブ

Dedicated

輸送専用容器transportation
vehicleIllustration of the method of transferring unitized structures©International Research Institute for Nuclear Decommissioning2. Accomplishments of Related Projects Implemented in FY2019-20

No.13(5) Top access method◼ Issues in top access method: Items related to this project are excerpted from the Fuel Debris Retrieval FY2020 Final Report*1
No.

1

2

3

Issue

Overview

This project

Method for cutting structures otherthan the reactor bottom

During the conceptual study, cutting the shroud
into upper and lower parts was considered as awork step. The method of cutting the reactor
internal structures including the shroud will be reexamined and studies will be conducted on
substantiation of the cutting method.

Refer to 6.2) (1) ①

Substantiation of the large transfer
container

Conceptual studies were conducted on largetransfer containers (dedicated transportation
containers) for transferring structures up to the
New building. In the future, the structure of largetransfer containers will be substantiated, andstudies will be conducted on the structural viability
including manufacturing capability, etc.

Refer to 6.2) (1) ②

Substantiation of transportationequipment

Cutting structures that cannot be directly stored inlarge containers in the additional building wasconsidered as a work step in the conceptual study.
Also, localized shielding will be added forstructures that have a high radiation dose rate.
Hence, substantiation of the means fortransporting the retrieved structures will be
studied, and revision of the work steps will beconsidered in accordance with the workability at
the additional building.

Refer to 6.2) (1) ③*1： “Development of Technology for Further Increasing the Scale of Retrieval of Fuel Debris and Reactor Internal Structures” FY2020 Final Report (March 2021)©International Research Institute for Nuclear Decommissioning3. Project Overview

No.14

3. 1. Collaboration with other projects
Isolation Technology for Preventing
Spread of Contamination
Sharing the status of studies

Development of Isolation Technology for Preventing
Spread of Contamination while Retrieving andTransporting Large Structures
Sharing of technicalchallenges

Continuous
monitoring
Development of System for Continuous
Monitoring Inside the PCV

Sharing of investigation needs/results

Development of Safety
SystemDevelopment of Liquid/Gas Phase Systems,
Criticality Control Technology

Sharing of analysis needs/results
Sharing the statusof studies

Development of Fuel
Debris Retrieval Method➢ Development of Side Access Method➢ Development of Top Access Method

Internal
Investigation

Characterization
Development of Analysis and Estimation
Technology for Characterization of Fuel Debris
Coordination between
containing/transfer and methods

Containing, Transfer
and Storage
Technologies

Development of Technology
for Investigation inside RPV・Sharing of safety scenarios
Development of Technology for
Detailed Investigation inside PCV

Gradually Increasing
the Scale of Fuel
Debris Retrieval
Development of Technology for Increasing
the Scale of Fuel Debris Retrieval in Stages

Sharing of technical challenges

・Coordination ofwork steps

Technology for Ensuring
SafetyDevelopment of Technology Related toEnsuring Safety during Fuel Debris Retrieval

Development of Technology for Containing,
Transfer and Storage of Fuel Debris
Coordination of collection/transfer and methods

Solid waste
Research and Development for Treatment andDisposal of Solid Radioactive Waste

In this project, joint meetings will be conducted as required in coordination with the above-mentioned projects.
©International Research Institute for Nuclear DecommissioningNo.15

3. Project Overview
3. 2 Development items involving
solicitation and implementation policy
1) Development of side access method(1) Development of the method of installing
access equipment① Installation of large heavy structures
・Verification of the feasibility of detailing andinstallation method of the cell structure to beinstalled inside of the R/B or the structure of
the access equipment② PCV connection sleeve installation andwelding by remote operation
・ Study/feasibility verification of methods forremote installation and welding, inspection,
maintenance, etc. of the sleeve① Installation of large heavy structures
Base plate
DebrisretrievalcellShieldingdoor

Maintenance
cell

Cell
adapter

Canistercell

LLW
Debristransportation transportation
cask cell
cask cell② PCV connection sleeve installation andwelding by remote operation
Additional
増設建屋
building

Sleeveスリーブ

PCV③ Installation of shield
Study/feasibility verification of the method ofadditional installation of access tunnel shield
for reducing the load of the ancillary facilities

Access tunnel
アクセストンネル

Illustration ofsleeve welding④ Disassembly of shield plug

Frame

③ Installation of shield
Main body ofaccess tunnel

Concrete blocks④ Disassembly of shield plug
・ Study/feasibility verification of technology
related to remote disassembly of the shield
plug, etc. (shield plug, block-out) which is alarge and heavy object

Breaker

Additional installation shielding
using iron balls

Iron balls
Hose
Rail
Cell
©International Research Institute for Nuclear Decommissioning3. Project Overview

No.16

3. 2 Development items involving
solicitation and implementation policy（2）① HVH disassembly
Cuttingline
切断線1) Development of side access method(2) Development of disassembly andremoval technology① HVH disassembly・Study/feasibility verification of themethods for HVH removal considering fall
prevention and remote operation② Disassembly of CRD exchanger
・Study/feasibility verification of themethods for disassembling and removing
the CRD exchanger, which is a large
structure, considering remote operation inlimited space with limited equipment③ Interfering objects removal from pumppit・Study/feasibility verification of themethods for remotely cutting andtransferring interfering objects such as
existing pumps, etc. from inside the pump
pit

チップソー
Tip saw

HVH
disassembly
HVH解体ロボット
robot

パネル
Panel

HVH
disassembly
HVH解体ロボット
robot

パネル
Panel

(2)② Disassembly of CRD exchanger
Equipment for
切断片transferring
cut
搬出装置
pieces

Suspending the cutting tools and揚重ワイヤによる切断ツール・ロボ
robotsand lifting the cut pieces with
吊り降ろし、切断片吊り上げ
the hoisting wire
CRD
CRD
交換機
exchanger

Where cut
切断片arepieces積載部
loadedプラット

Platform
フォーム

Carrying搬出入
in/outレール
rail
Robot for CRD
CRD交換機exchanger
撤去ロボット
removal(2)③ Interfering objects removal from pump pit(3)① Remotely operated tip tool for retrieval

Simulated pump(3) Advancement and development of
retrieval methods① Remotely operated tip tool for retrieval・ Verification of the methods fordisassembly and removal of structuresinside PCV, and the procedures forprocessing and collecting fuel debris.
・ Acquisition of data for throughput
evaluation.

Circular cutter test

Slinging jig

Small robot↑

Mock-up (left) andelement test equipment← Operator console©International Research Institute for Nuclear Decommissioning3. Project Overview
3. 2 Development items involving
solicitation and implementation policy
2) Development of top access method(1) Development of technology for realizing
the concept of retrieving large structures① Method of cutting large structures
・ Study/feasibility verification of the methods
for cutting and separating structures that area mixture of metallic and ceramic material
including the filler material
・ Study/site applicability evaluation of themethods for transferring the structures after
they have been cut, until the structures areloaded on to the large transportationequipment② Large transfer container
・Development of the conceptual structure of
the transfer system including the method ofplacing the structures in the large transfer
container・Detailed study/feasibility verification related
to the air-tight structure of the large transfer
container as a whole, manufacturing
procedures, etc.
③ Large transportation equipment
・Investigation and studies related to themethods of transporting large and heavy
contaminated structures in terms of theadaptability to the air-tight gate, etc.
・ Structural examination/on-site applicability
evaluation of the transportation equipment
including the drive mechanism

No.17① Method of cutting large structures
揚重機
Crane

Laser + WJ
head

連絡通路
Passageway

Scope of studies
本事業の検討範囲
conducted
in this project

Connection
接続スリーブ sleeve（PCVと連絡通路間を(connecting
the PCV接続）
andthe passageway)
Structures other than
炉内構造物以外の構
the reactor internal
造物
structures(PCV head,（PCVヘッド、RPVヘッ
RPV head, etc.)ド等）→ Results of the⇒要素試験結果は、
element tests have「2021年度実施分
beenreported in the
成果*」で報告済“Accomplishment
Report for FY2021*”

Test piece

Reactorinternal
炉内構造物
structures(Dryer,（ドライヤ、セパレータ、
separator,
shroud,シュラウド、燃料デブリ
fuel等） debris, etc.)

Study of methods for cutting the reactor
2019-20年度
bottom and implementation of element
炉底部切断の検討・要素試験実施
tests③ Large transportation equipment
Crane(Passageway)② Large transfer container
可動フランジMovableflangeUpper lid
上蓋

Lower lid
下蓋Shielding
cart
Passageway
Transportation cart
(Localizedshielding)*Accomplishment Report for FY2021: https://irid.or.jp/wp-content/uploads/2022/08/2022007_deburitoridashi.pdf

Large transfer
container

大型搬出容器← To bedeveloped
during this
PJ

©International Research Institute for Nuclear Decommissioning3. Project Overview

No.18

3. 2 Development items involving solicitation and implementation policy
Development items involving
solicitation

Implementation policy

Reference pages

1) Development of side access method(1) Development of the method of
installing access equipment① Installation of large heavy structures
The pre-conditions and required specifications will be clearly specified, the cell structure installedinside R/B and the structure of the access equipment will be detailed, the installation method will
be studied, and the feasibility will be verified based on the on-site applicability of the method
including the procedures, installation accuracy and efficiency of the overall method, by element
tests using simulated test specimens, etc.

No. 27 to 152② PCV connection sleeve installation and welding by remote operation
The requirements for installation of the sleeve, etc. connected to the PCV by remote operation will
be consolidated, the method of installation by remote operation, the equipment and devices, andprocedures will be studied, and feasibility of the requirements such as accuracy assessment, etc.
will be verified by element tests using simulated test pieces. Also, the requirements pertaining towelding, inspection and maintenance of the sleeve, etc. as containment technology for theconnection part will be consolidated, the method of implementing the series of operations
including welding procedures, inspection and maintenance by remote operation will be studied,and the feasibility and workability of welding will be verified by means of verification tests using
simulated test pieces.

No. 153 to 228③ Installation of shield
In order to reduce the floor load of the ancillary facilities required for transportation to the inside of
the R/B, the R/B, etc. streamlining the structure of the access tunnel shield, and the transportation/ installation methods will be studied and development will be carried out.

No. 229 to 264④ Disassembly of shield plug
As the shield plug, etc. (shield plug, block out) in front of the existing equipment hatch, which is alarge and heavy object made of concrete, etc. needs to be removed, technology related to safeand efficient disassembly in confined spaces will be studied and developed.

No. 265 to 293① HVH disassemblyUpon studying and organizing the requirements for disassembling and removing HVH, element
tests on disassembly and removal by means of remote disassembly equipment and devices
developed so far using simulated test pieces will be planned and implemented considering remote
operation in limited space, and the feasibility of specific cutting/collection methods will be verified.

No. 294 to 321② Disassembly of CRD exchanger
Upon studying and organizing the requirements for disassembling and removing the CRD
exchanger, element tests using simulated test pieces will be planned and implemented
considering remote operation in limited space, and the feasibility of specific cutting/collection
methods will be verified.

No. 322 to 381(2) Development of disassembly andremoval technology©International Research Institute for Nuclear Decommissioning3. Project Overview

No.19

3. 2 Development items involving solicitation and implementation policy
Development items involving
solicitation

Implementation policy

Reference pages

1) Development of side access method(2) Development of disassembly andremoval technology③ Interfering objects removal from pump pit
The gap between the inner surface of the pit and the pump is small, and it is not easy to access withtools, etc. Hence, the method of confirming the status of the target objects by means of images capturedby the camera, and then cutting, etc. and transferring will be studied in detail, and feasibility will beverified by element tests.

No. 382 to 411(3) Advancement and development of
retrieval methods① Remotely operated tip tool for retrieval
The procedures for removing structures from inside the PCV, processing fuel debris and collecting in unit
cans, operability, efficiency of the tip tools, etc. will be verified by studying the tip tools and operation
systems and conducting element tests, etc., and the viability of the series of operations will be verified.
Also, the actual data on the work procedures will be acquired and consolidated, and data for evaluating
the throughput will be obtained.

No. 412 to 538① Method of cutting large structures
The method of cutting and separation taking metal in-core structures and ceramic fuel debris into
consideration will be studied, and element tests will be conducted using simulated test pieces. Also, themethod of transferring cut structures including PCV head, etc. until the structures are loaded on to thelarge transfer equipment, will be studied, and on-site applicability will be evaluated.

No. 539 to 614② Large transfer container
Detailed study will be conducted on the conceptual structure of the transfer system including the methodof placing the structures in the large transfer container, the air-tightness and shield structure of the largetransfer container as a whole including the lid part, manufacturing procedures, etc. Also, the structure of
the large transfer container will have to be such that it is easy to decontaminate the inside of thecontainer assuming it will be re-used. Furthermore, full-scale transfer containers will be test
manufactured, their performance will be verified by element tests, viability will be verified and issues in
on-site application will be identified.

No. 615 to 648③ Large transportation equipment
The preconditions of the large transportation equipment and the required development items will be
studied and consolidated, the method for transporting large heavy contaminated structures with certainty
will be investigated and studied in terms of the adaptability to the air-tight gate, etc., on-site applicabilityof the large transportation equipment will be evaluated by element tests and structural examination of thetransportation equipment including the drive mechanism, and issues will be identified.

No. 649 to 669

2) Development of top access method(1) Development of technology forrealizing the concept of retrieving
large structures©International Research Institute for Nuclear Decommissioning3. Project Overview

No.20

3. 3 Points to be noted while executing this project
The points to be noted while executing the plans under this project are described below.
[Points to be noted]
During the study, fuel debris retrieval method will be developed while considering
handling capability and maintenance methods of the equipment that will be handled

remotely, in terms of the following.
・As the equipment will be installed in areas with high radiation, as a general rule,maintenance will be carried out remotely.
・The contamination of the equipment and the required decontamination will need tobe taken into consideration.
・Limited work area will be available for maintenance work.
・Waste generated during maintenance work will need to be minimized as much as
possible.
・Installation and handling of criticality monitoring equipment will need to beconsidered.

©International Research Institute for Nuclear Decommissioning4. Implementation燃料デブリ取り出し工法の開発
schedule of this実施スケジュール（1/4）
project

類

法の開発
備の設置工

造物の開発

Planned：計画
Revise：見直しd
Actual：実績

Developmentof fuel debris retrieval
method Implementation schedule (1/4)
燃料デブリ取り出し工法の開発
実施スケジュール（1/4）
小分類
Large
classification
大分類

2021年度
2022年度FY20212021年度
2022年度FY2022
備考
Small小分類
classification
4月 5月
6月
7月 8月
9月
10月
11月
12月
1月
2月
3月
4月
5月
6月
7月
8月
1月 11月
2月 12月3月 JanDec Jan
Jun
Jul
Nov
Sept
Oct
Dec
Nov 12月
Oct 11月Aug
Apr
4月 May5月 Jun
6月 Jul
7月 Aug
8月 Sept
9月 10月
1月 Feb
2月 Mar
3月 Apr
4月 May
5月9月
6月10月
7月11月
8月 12月9月 10月
1月 Feb
2月 Mar3月

横取り出し工法の開発
1.１.Developmentof side(１) アクセス用設備の設置工
accessmethoda. 概念検討
法の開発(1) Developmentof① 大型重量構造物の設置
method for installingb. 要素試験計画
access equipment① Installation of largec. 試験準備/heavy structures
試験装置試作

d. 要素試験
e. まとめa. 概念検討

No.21[Legend]【凡例】

Remarks
備考

study of the structure of access equipment
a.a.Detailed
study of the Detailed
アクセス用設備の構造詳細検討
概念検討
アクセス用設備のstructure of access
構造詳細検討equipment
b.b.Detailingand study
アクセス用設備のof the steps for
据付ステップ詳
installing
accessequipment
細化検討

Detailingand study of the steps for installing access equipment
要素試験計画
アクセス用設備の据付ステップ詳細化検討
試験準備/試験装置試作
Verificationof the installation procedures through element tests
据付手順の要素試験検証

c.c.
Verificationof the
据付手順の要素installation procedures
試験検証
throughelement test

燃料デブリ取り出
d.d.Detailingof the workinsidethe cell of the
し設備のセル内
fuel debris retrieval
作業の詳細化
equipment
報告書作成
e.e.Report
creation

リーブ遠隔設

要素試験
燃料デブリ取り出し設備のセル内作業の詳細化
Detailingof the work inside the cell of the fuel debris retrieval equipment

まとめ

概念検討

報告書作成
Report creation

要素試験計画
b. 要素試験計画②Remoteinstallation
and welding of the PCV②
ＰＣＶ 接続スリーブ遠隔設
c. 試験準備/connection
sleeve
置・溶接
試験装置試作
d. 要素試験
e. まとめConceptual
概念検討study
a.a.Conceptual
概念検討study

Element
test plan
要素試験計画
試験準備/試験装置試作

b. Element test planb. 要素試験計画

c. Testpreparation/test
c. 試験準備/manufacturing of test
試験装置試作
equipment

Test preparation/test
manufacturing of test equipment
試験準備/試験装置試作
要素試験
Element
testまとめ
要素試験

d. 要素試験
d. Element tests

まとめ
e.e.Summarya. 概念検討
a. Conceptual study

b. 要素試験計画③Shield
installation③ 遮蔽体設置

c. 試験準備/
試験装置試作
d. 要素試験
e. まとめa. 概念検討
b. Element test planb. 要素試験計画

c. Testpreparation/test
c. 試験準備/manufacturing of test
試験装置試作
equipmentd. 要素試験まとめ
Summary

概念検討

Conceptual
study
概念検討
要素試験計画Element
test plan
要素試験計画
試験準備/試験装置試作
Test preparation/test試験準備/試験装置試作
manufacturing of test equipment
要素試験

・Since it took time
・試験内容検討に時
to study the
間を要したため、試験
contents of the test,
準備工程および試験
the test
工程を見直し。
preparation
schedule and thetest schedule wererevised.

Element
test
要素試験
まとめ

d. Element tests

まとめ
e.e.Summary

Summary
まとめ©International Research Institute for Nuclear Decommissioning

の開発
の設置工

物の開発

ーブ遠隔設

燃料デブリ取り出し工法の開発 実施スケジュール（1/4）
4. Implementation scheduleof this project

小分類[Legend]【凡例】
Planned：計画
Revised：見直し
Actual：実績

2021年度
2022年度schedule (2/4)
Developmentof fuel debris retrieval method
Implementation
燃料デブリ取り出し工法の開発
実施スケジュール（2/4）
4月 5月 6月 7月 8月 9月 10月 11月 12月 1月 2月 3月 4月 5月 6月 7月 8月 9月 10月 11月 12月 1月 2月 3月

Large大分類
classification

Small
小分類
classification

１.Development
横取り出し工法の開発
1.
of sidea.
概念検討(１) アクセス用設備の設置工
accessmethod(1) Developmentof method法の開発
b.
要素試験計画foraccess④ installing
シールドプラグの解体
equipmentc.
④ 試験準備/Disassembly of shield
試験装置試作
plug

d. 要素試験
e. まとめ

備考

FY20212021年度
2022年度FY2022
Apr 5月Aug Sept
Oct 11月
Dec
Nov 12月
Apr 5月Feb 3月May 6月Jul
Dec 1月Jan 2月Feb 3月Mar 4月May 6月Jul
Jan 2月Jun 7月Aug Sept
Oct 11月
Mar
Jun 7月Nov 12月
4月
8月
9月 10月
8月
9月 10月
1月
概念検討
Conceptual
概念検討 study

a. Conceptual study

a. 概念検討

要素試験計画Element
test plan
要素試験計画b. Element test planb. 要素試験計画

試験準備/試験装置試作
Test preparation/test
manufacturing of test equipment
試験準備/試験装置試作

c. c.
Test
preparation/test
試験準備/
manufacturingof test
試験装置試作
equipment

No.22

備考
Remarks
・試験計画立案(試験・Sinceit took time to
項目等の決定)、試験
draft
the test plan(finalize
the test items,
体準備に時間を要し
etc.)
and prepare the
たため、試験準備工程
test
pieces, the test
および試験工程を見preparation
schedule直し。
and test schedule
were revised.

要素試験
Elementtest
要素試験

d. 要素試験まとめ

d. Element tests

Summaryまとめe. まとめe. Summary

概念検討
(2)
Developmentof(２)概念検討
解体・撤去技術の開発
a.
disassembly and removal
technology①要素試験計画
HVH解体
b.
① HVH disassemblyc. 試験準備/
試験装置試作
d. 要素試験
e. まとめa. Conceptual study

a. 概念検討

要素試験計画Element
test plan
要素試験計画b. Element test planb. 要素試験計画
Test preparation/test manufacturing of test equipment
試験準備/試験装置試作
試験準備/試験装置試作

c.c.
Test
preparation/test
試験準備/
manufacturingof test
試験装置試作
equipment

要素試験

d. 要素試験

Element
要素試験test

d. Element tests

まとめe. まとめe. Summary

概念検討

a. 概念検討

a. Conceptual study

a. 概念検討② Disassembly of CRD② CRD交換機の解体
exchanger

b. Element test planc. 試験準備/
試験装置試作

c. Testpreparation/test
c. 試験準備/manufacturingof test
試験装置試作
equipmentd. 要素試験

要素試験
d.d.Element
tests

b. 要素試験計画

e. まとめ・HVH解体、CRD交換
・Sincethe tests on
HVH
disassembly,
機の解体、ポンプピット
CRD
exchanger
内干渉物撤去の試験
disassembly
and実施場所が同一のたinterfering
objects
め、実施時期を見直removal from the
し。
pump pit are
conducted at thesame location, thetime ofimplementation wasrevised.

Conceptual study
概念検討

Summary
まとめ・Basictests are・IRID内レビュー等でconducted in FY2021の指摘事項を踏まえ、based on matters
2021年度中に基礎試
indicated
during the
IRIDinternal review, etc.
験を実施した。結果をThe
results are reflected
概念検討および要素
in the conceptual study
試験計画に反映する。
and element test plan.

概念検討 study
Conceptual
Element
test plan
要素試験計画要素試験計画

b. 要素試験計画

e.e.Summary
まとめ

Test
preparation/test manufacturing of test equipment
試験準備/試験装置試作
試験準備/試験装置試作
Basic
tests related to fall
落下防止・切断片搬出
prevention and transferring
に関する基礎試験
of cutpieces・試験計画(試験内容

Element
test
要素試験

要素試験
まとめ

Summary
まとめ・Sinceit took time to検討)、準備に時間を
plan
the tests (studying
要したため、試験工程
the test contents) andを見直し。
preparefor them, thetest schedule wasrevised.

©International Research Institute for Nuclear Decommissioning

開発
開発
設置工
設置工

の開発
の開発

ブ遠隔設
ブ遠隔設

燃料デブリ取り出し工法の開発
燃料デブリ取り出し工法の開発 実施スケジュール（1/4）
実施スケジュール（1/4）

【凡例】
【凡例】
[Legend]

4. Implementation schedule of this project：計画
Planned：計画：見直し
Revised：見直し：実績
Actual：実績

2021年度
2022年度
2021年度
2022年度
備考
備考
Developmentof
fueldebrisretrievalmethodImplementation
4月 5月
5月 6月
6月 7月
8月 9月
9月 10月10月 11月
11月 12月
12月
1月 2月
2月 3月
3月 4月
4月 5月
5月 6月
6月
7月 8月
8月 9月
9月 10月10月 11月
11月schedule
12月 1月
1月(3/4)2月 3月
燃料デブリ取り出し工法の開発
実施スケジュール（3/4）
4月
7月 8月
1月
7月
12月
2月
3月
FY2021
FY2022
2021年度
2022年度Small
Large大分類
classification
小分類
概念検討
classification
概念検討
May
Dec 1月
Mar
Jun
Aug
Aug
Oct 11月
Jan Feb
Dec
Jun
Jul
Jan
Feb
Apr
Nov 12月
Apr
Mar
Sept
May
Jul
Sept
Oct 11月
4月 5月 6月 7月 8月 9月 10月
2月 3月
Nov 12月 1月 2月 3月 4月 5月 6月 7月 8月 9月 10月
a.
a. 概念検討
概念検討

No.23

小分類
小分類

1.１.
Developmentof side
横取り出し工法の開発
accessmethod(２)
解体・撤去技術の開発
b.
要素試験計画b.
要素試験計画(2) Development ofdisassembly and removal③試験準備/
ポンプピット内干渉物撤去
c.
technologyc.
試験準備/③ 試験装置試作
Removalof interfering
試験装置試作
objects from the pump pit

d.
d. 要素試験
要素試験
e.
e. まとめまとめ

a. 概念検討
概念検討a.
(3) Advancement andb.development
要素試験計画(３)
取り出し工法の高度化開b.
要素試験計画of retrieval
発
methodc.
Remotely
operated tip tool
①試験準備/
取り出し用遠隔先端ツー
c.①
試験準備/
for試験装置試作
retrieval
試験装置試作ルd. 要素試験
要素試験
d.
e. まとめまとめ
e.

a. Conceptual study

a. 概念検討

Element
test plan
要素試験計画

試験準備/試験装置試作
試験準備/試験装置試作

b. Element test planb. 要素試験計画

Test
preparation/test manufacturing of test equipment
試験準備/試験装置試作

c. Testpreparation/test
c. 試験準備/of test
manufacturing
equipment
試験装置試作要素試験
要素試験
Element
要素試験test

まとめ
まとめ

要素試験
d.d.Elementtests
e. まとめe. Summarya. Study of measures
to enhancea. スループット改善
throughput

Summary
まとめ・Sincethe tests on
・HVH解体、CRD交換
HVH
disassembly,
機の解体、ポンプピット
CRD exchanger
内干渉物撤去の試験
disassembly and実施場所が同一のたinterfering
objects
め、実施時期を見直removalfrom theし。 pit are
pump
conducted at thesame location, thetime ofimplementation wasrevised.

概念検討
概念検討
Study
of measures
to enhance throughput
スループット改善策の検討
要素試験計画要素試験計画策の検討

Tip
tool element
test plan and preparation
先端ツール要素試験計画・準備
試験準備/試験装置試作

試験準備/試験装置試作

b. Tip tool elementb. plan
先端ツール要素test
andpreparation
試験計画・準備

要素試験
Element
test (Processing test forevaluating
throughput)（スループット評価用加工試験）

要素試験
要素試験

c. Element test
(Processing
test forc. 要素試験（スevaluating throughput)

まとめ
まとめ

ループット評価用
加工試験）

d. Study of operating
systema.
a. 概念検討
概念検討

d. 操作システムの検討

b.
b. 要素試験計画
要素試験計画

e. Development andsimulation verification
操作システムのofe.operating
systemc.
c. 試験準備/
試験準備/
試験装置試作試験装置試作

Conceptual
概念検討study

要素試験計画要素試験計画

Remarks
備考

開発・シミュレー
ション検証

d.
d. 要素試験
要素試験

f. Element tests(Series of operations
f. 要素試験（操作using
the operating
system)システムを使ったe.
e. まとめまとめ

g. Report creation

一連作業）

Study of operating system
操作システムの検討
概念検討
概念検討
Development and simulation verification of

要素試験計画操作システムの開発・シミュレーション検証
operatingsystem
要素試験計画

試験準備/試験装置試作
試験準備/試験装置試作
Element tests (Series of operations using
要素試験（操作システムを使った一連作業）
theoperating system)

要素試験
要素試験

報告書作成
まとめ
creation
まとめ Reportg. 報告書作成©International Research Institute for Nuclear Decommissioning燃料デブリ取り出し工法の開発 実施スケジュール（1/4）

実施スケジュール（1/4）
4. Implementation燃料デブリ取り出し工法の開発
schedule of this project

2021年度
2022年度
2021年度
2022年度Developmentof fuel debris retrieval method
Implementation
schedule (4/4)
燃料デブリ取り出し工法の開発
実施スケジュール（4/4）
4月
5月
6月
7月
8月
9月
10月
11月
12月
1月
2月
3月
4月
5月
6月
7月
8月
9月10月
10月11月11月12月
12月1月
1月 2月
2月 3月
3月
4月 5月 6月 7月 8月 9月 10月 11月 12月 1月 2月 3月 4月 5月 6月 7月 8月 9月

類

小分類
小分類

法の開発
法の開発
備の設置工
備の設置工

Large大分類
classification

造物の開発
物の開発

リーブ遠隔設ーブ遠隔設[Legend]【凡例】【凡例】
Planned：計画：計画
Revised：見直し：見直し
Actual
：実績
：実績

Small
小分類
classification

概念検討
２.
上取り出し工法の開発
2.
Developmentof topa.a.
概念検討(１) 大型構造物の取り出しコ
accessmethodンセプト 実現に向けた技(1)
Developmentof
要素試験計画b.b.
要素試験計画術開発 for realizing thetechnology
conceptof retrieving large①試験準備/
大型切断工法c.c.
試験準備/
structures
試験装置試作試験装置試作①
Method of cutting large
structures

要素試験
d.d.要素試験

a. Conceptual study

a. 概念検討

Conceptual
概念検討 study
Element
test plan
要素試験計画要素試験計画
b.b.Element
test plan

Element
test plan (Cutting reactor internal structures)
要素試験計画（炉内構造物切断）試験準備/試験装置試作
試験準備/試験装置試作
Test preparation/test manufacturing of test equipment
試験準備/試験装置試作

c. Testc. 試験準備/preparation/test
manufacturingof test
試験装置試作
equipment

要素試験
要素試験

Element test
要素試験（炉内構造物切断）(Cutting
reactor internal structures)

要素試験（RPVヘッド解体）
Element
tests (RPV head disassembly)

d. 要素試験まとめ
e.e.まとめ

まとめ
まとめ

d. Element tests

概念検討
概念検討
a. Conceptual study

要素試験計画b.b.
②要素試験計画
Large transfer container② 大型搬出容器

b. Element test plan

試験準備/
c.c.試験準備/
試験装置試作試験装置試作

c. Testpreparation/test
c. 試験準備/manufacturingof test
試験装置試作
equipment

要素試験
d.d.要素試験

a. 概念検討

要素試験計画要素試験計画Element
test plan
要素試験計画

b. 要素試験計画

試験準備/試験装置試作
Test
preparation/test manufacturing of test equipment
試験準備/試験装置試作
試験準備/試験装置試作

要素試験
要素試験

d. 要素試験

Element
tests
要素試験

まとめ
まとめ

e. まとめe. Summarya. Conceptual study③
Large transfer
概念検討
a.a.
概念検討

a. 概念検討

containers③ 大型搬送装置

b.b.Element
test plan
要素試験計画試験準備/
c.c.試験準備/
試験装置試作試験装置試作

c. Testc. 試験準備/preparation/test
manufacturingof test
試験装置試作
equipment

要素試験計画
b.b.要素試験計画

概念検討
概念検討

Element test plan

要素試験計画要素試験計画要素試験計画

試験準備/試験装置試作
試験準備/試験装置試作

Element
tests
要素試験

まとめ
まとめ

e. Summary

Major
milestones
主要なマイルストン

Test
preparation/test manufacturing of test equipment
試験準備/試験装置試作

要素試験
要素試験

d. Element tests

e. まとめまとめe.e.まとめ

Summary
まとめConceptual
概念検討 study

d. 要素試験

要素試験
d.d.要素試験

・As
the time of the RPV
・RPVヘッドスタッドボ
headstud bolt cutting
ルト切断要素試験に
element test overlapped
ついて、他試験と試験with the test time of
時期が重複するため、
othertests, test
preparations
were made2021年度中に要素試
assuming
the element
験を実施することで試
tests would be験準備を実施し、要素
conducted in FY2021,
試験を実施。２１年３月
andthe element tests
were
conducted. Theyに完了。
were completed in
March 2021.

Element
tests were
要素試験は２２年12月
completedに完了。 in December
2022

Conceptual study
概念検討

d. Element tests

まとめe.e.まとめ

備考
Remarks

Summaryまとめ

e.e.Summary
まとめ

概念検討
a.a.概念検討

備考
備考

FY2022
2021年度
2022年度FY2021
Jul 概念検討
Oct 11月
Jan Feb
Apr May
Aug Sept
Apr May
Dec 1月Mar
Dec 1月Mar 4月Jul Aug
Jan 2月Feb 3月Nov 12月
Oct 11月
Nov 12月
4月
5月 Jun
6月 7月
8月
9月 10月
2月 3月
5月 Jun
6月 7月
8月 Sept
9月 10月
概念検討

要素試験計画要素試験計画No.24

Interimreport中間報告

Annualreport
年度末報告

Interimreport中間報告

Summary
まとめ・Afterorganizing the・作業容器や隔離
issuesbased on the
シートを含めた搬出入
steps for carrying in/out
ステップに基づく課題
thework container and
整理後に要素試験項
isolation
sheet, element
test
items, etc. are
目の抽出等を行い要
identified
and the
素試験計画を立案。
element test plan is
・搬出入ステップ検討
drafted.
および課題整理に時・Sinceit took time tostudy
the steps for
間を要したため、試験
carrying
in/out and to計画の立案は2022年
organize the issues, the度から実施。
element test plan wasdrafted from FY2022.

Finalreport
最終報告
Presentationof results report
実績報告書提出©International Research Institute for Nuclear Decommissioning5. Project Organization

No.25

International Research Institute for Nuclear
Decommissioning (IRID)➢ Coordination of overall planning and technology
management➢ Coordination of technology administration including
technology development progress management

Tokyo Electric Power Company
Holdings, Inc.
➢ Various coordination for site
application

Project teams to cooperate fortechnological development

Hitachi-GE Nuclear Energy, Ltd.
[Element tests, technical development]
1) Development for side retrieval method(1) Development of the method of installing
access equipment② PCV connection sleeve installation andwelding by remote operation③ Installation of shield④ Disassembly of shield plug(2) Development of disassembly and removal
technology① HVH disassembly② Disassembly of CRD exchanger③ Interfering objects removal from pump pit
2) Development of top access method(1) Development of technology for realizing theconcept of retrieving large structures① Method of cutting large structures② Large transfer container③ Large transportation equipment

Mitsubishi Heavy Industries, Ltd.
[Element test, technical development]
1) Development for side access method(1) Development of the method of installing
access equipment① Installation of large heavy structures(3) Advancement and development of retrieval
methods① Remotely operated tip tool for retrieval

Development of Fuel Debris Retrieval Method(Development of Isolation Technology for
Preventing Spread of Contamination while
Retrieving and Transporting Large Structures）
Development of technology for further increasing
the scale of retrieval of fuel debris and reactor
internals(Development of technology related to ensuringsafety during fuel debris retrieval)
Development of safety systems (Liquid/gas phasesystems, criticality control technology)
Development of analysis and estimation
technology for characterization of fuel debris

Development of technology for detailed
investigation inside PCV (Field validation of thetechnology for detailed internal investigation using
X-6 penetration)
Development of technology for detailed
investigation inside PCV(On-site demonstration of technology for detailed
investigation considering deposit measures)
Development of technology supporting integrated
management of decommissioning at Fukushima
Daiichi Nuclear Power Station(Development of systems for continuous
monitoring inside PCV)

Development of technology for investigation
inside RPVDevelopment of technology for gradually
increasing the retrieval scale of fuel debris
Research and development for treatment anddisposal of solid waste

Development of technology for containing, transfer
and storage of fuel debris©International Research Institute for Nuclear Decommissioning5. Project Organization

No.26

Main sub-contracting details
Hitachi-GE Nuclear Energy, Ltd.
[Sub-contracting details]
・ PCV connection sleeve remote installation test,
additional access tunnel shield installation test,
HVH disassembly element test,
CRD exchanger disassembly element test,
pump pit interfering objects removal element test,
large transportation equipment element test
(Toko Corporation)
・ PCV connection sleeve remote welding test,element tests related to RPV head disassembly,
test manufacturing of large transfer containers,
air-tightness test
(Mitsubishi Heavy Industries, Ltd. (Former Mitsubishi Power,Ltd.))・ Elemental test related to the method of cutting large reactor
internal structures(Sugino Machine Limited)・ Study related to filler material for the top access unitizedlarge structures transfer method

Mitsubishi Heavy Industries, Ltd.
[Sub-contracting details]・ Design assistance related to detailing of cell structure(MHI NS Engineering Co., Ltd.)・ Design assistance related to detailing of the accessequipment fitting method (MHI NS Engineering Co., Ltd.)・ Cell adapter remote installability verification test
（DIA F Engineering, Ltd., MHI NUSEC, LTD.)・ Indoor and outdoor cell installation frame placement study(Nihon Kensetu Kogyo Co. Ltd.)・ Installation position setting technology verification test
（DIA F Engineering, Ltd., MHI NUSEC, LTD.)
・ Design assistance related to the method of processing
structures and fuel debris(MHI NS Engineering Co., Ltd.)・ Structures and fuel debris processing test
(MHI NS Engineering Co., Ltd.)・Evaluation of validity of the trajectory calculation logic for
avoiding obstacles(Kobe University)
・Coding of the software for avoiding obstacles(MHI NS Engineering Co., Ltd.)(University of Tokyo)
・ Design assistance related to the study of side accessmethod,shield plug disassembly elemental test
(Hitachi Plant Construction, Ltd.)・ Design assistance related to the study of top access method(JTEC Corporation)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project

No.27

1) Development of side access method(1) Development of the method for installing access equipment① Installation of large heavy structures
The installation of cells, which are large heavy structures, has been studied to be used as accessequipment for the side access method, with the purpose of further increasing the scale of retrieval of fueldebris and reactor internal structures. For precise cell installation inside the R/B, ensuring of installation
accuracy and optimization of installation work need to be studied and related development needs to be
carried out with respect to the cell structure and connection with the PCV.
In order to install the cell structure, which is a large heavy structure, on the PCV connecting part, the cellstructure needs to be positioned accurately on the PCV connecting part while keeping within the load limit
for the floor inside R/B, and the connection to the PCV opening needs to be accomplished remotely via thestructure equipped with confinement function and a function for dealing with displacement caused byearthquakes. The method of installing the access equipment for the cell structure inside the R/B will be
studied, verification tests will be conducted, and the efficiency of the method as a whole and feasibility ofthe procedures will be verified.
As the pedestal opening cannot be modified and changed easily, the cell structure needs to be installedaccurately by remote operation while sufficiently considering the mutual correlation between the location of
the X-6 penetration, which is where the access equipment is installed, and the location of the pedestal
opening (axis joining both openings), when both openings are connected. As the access equipment isinstalled along the axis leading to the pedestal opening from the X-6 penetration, first, the method ofcarrying-in and remotely installing the cell structure meeting this requirement via the connection structure
will be studied while taking earthquakes measures into consideration. Then, the viability will be verified
based on the on-site applicability of the method including the procedures, installation accuracy andefficiency, by elemental tests using simulated test pieces, etc.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]

No.28① Installation of large heavy structures
Table of Contents(1) Development results achieved so far and correlation with this project(2) Background and purpose of this research(3) Project Goals(4) Development schedule(5) Implementation items, their mutual correlation, and correlation with other research(6) Implementation items(6)-1: a. Detailed study of the structure of the access equipment(6)-2: b. Study on detailing of procedures for installing the access equipment(6)-3-1: c. Verification of element test for the installation procedures(6)-3-2: c. Elemental test verification of installation procedures （Organizing therequired specifications of the equipment for remote installation)(6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment(7) Summary©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for
Installing Access Equipment]① Installation of large heavy structures(1) Development results achieved so far and correlation with this project[Upgrading of fundamental technology(FY2017-18)]

Equipment hatch cell
Carrying in/out cell

Fuel debris retrieval cell

Crane maintenance module

Mini cask cell
Shielding door

No.29

Equipment temporary storage module
Fuel debris
Maintenance retrieval cell
Shielding door
cell
Cell adapter

Canister cell
Cask cell••

Study of the composition of fueldebris retrieval equipment and the
proposed layout
Study of the method of installing thesuspension bridge type cell

Waste transfer cell
Cell installation deck
Mini cask cell
Maintenance cell

Canister carrying in station
Canister cell

Access equipment
carrying-in/out port
Waste carrying-in/out port
Cask carrying-in/out port

Cell installation frame

Composition of the fuel debris retrieval
equipment (suspension bridge type cell)

Layout of the fuel debris retrieval equipment

Mini cask cell LLW transportation cask cell
[Further increasing the retrieval scale
Fuel debris retrieval cell
Canister cell Fuel debris transportation cask cell
(FY2019-20)]•

Substantiation of the access equipment(cell adapter, shielding door, cell) to beconnected to the PCV inside the R/B,
study and verification of feasibility of
installation method.

ShieldBiological
Shield Wall

Frame
structure

Debris retrieval cell

Reactor building wall

Frame for supporting the load of the cell
10. Work of making an opening on PCV
10 PCV
壁コンクリート開口作業
concretewall
遮へい扉（開口状態）
Shieldingdoor (open)

Transportation cask yard

イ
メ
ー
ジ
図

Illustrations•

Reactor building
Floor beam

11. Work of carrying-in and installing cell
11 セルアダプタの搬入・設置作業
adapter
Temporary cellfor 開口作業用仮セル
the work ofmaking an
openingCell

セルアダプタadapter

Material
機材搬出入台車
carrying-in/out
cart

Temporary cell
開口作業用仮セル
for the work ofmaking an
opening

Access equipment
temporary storage
space
Maintenance cell
Equipment transfer Equipment transfer
container
container yard

12. Preparation for installing cell inside the
12 建屋内セル設置準備
building
Temporary cellfor the work ofmakingan
開口作業用仮セル
openingCell

セルアダプタadapter

Material
機材搬出入台車
carrying-in/out
cart

Truck
Rail for carrying建屋内外結合
in/outthe cell for
セル搬出入用レール
linking the insideand outside of
the building

Fixedrail installation
固定レール設置台
platform

Cell connection
セル取り合い用フランジ
flange1)
Setting up the cell for the work of making an
1）開口作業用セル設営
opening2）開口作業（ガレキ等は搬入作業と逆手順で実施）
2)
Work of making an opening (Procedures
oppositeto those for carrying-in work are※開口作業の進捗に従い遮へい扉を少しずつ閉じる
手 followed for debris, etc.)
順 # The shielding door is gradually closed as thework of making the opening progresses.

1) Preliminary preparation for carrying-in cell
1）セルアダプタ搬入前準備
adapter (PCV wall surface cleaning / 3D shape(PCV壁面清掃・3D形状計測/セルアダプタ開先作業)
measurement/ Cell adapter groove work)
2) Loading the carrying-in/out cart on the outdoor
2）ヤード建屋クレーンで搬出入台車を屋外レールに搭載
rail with the help of a yard building crane3）機材搬出入台車にセルアダプタを搭載
3) Loading the cell adapter on the equipment
4）ケガキに位置合わせを行いながら設置
carrying-in/out cart
4) Installing while adjusting the position inaccordance with the layout markings

1)
Carrying-in and installing the fixed rail
1）固定レール設置台搬入・設置する。
installation platform
2）機材搬出入台車にセル取り合い用フランジを搭載
2)
Loading the cell connection flange on to theequipment
carrying-in/out cart
3）ケガキに位置合わせを行いながら設置
3) Installing while adjusting the position in4）遮へい扉閉止後、開口作業仮セル解体
accordance with the layout markings4) Disassembling the temporary cell for the work ofmaking an opening, after the shielding door isclosed・・ Studyof method ➡
of makingan opening A method that
開口工法検討PCV鋼板を損傷させない加工方法
would not damage the PCV steel plate・Installationof cell adapter
・ セルアダプタ据付・設置(Installation of sling and roller for carrying-in at the（開口部に吊ピース及び搬入用ローラの設置等）
opening)

Need for cell connection 遠隔搬入・設置工法
flange, remote carrying・・ セル取り合い用フランジ要否,
in and installation method
・・Method
作業時の仮設遮へい方法
of temporary shielding during work

Procedure•

Pillar

Installation
cell frame

Study on downsizing the cells installedinside R/B
Study of the method of supporting theload of the cells
Fuel debris retrieval
Study of the work steps involved in
preparatory cell
installing the fuel debris retrieval
Dual arm typerobot container
equipment[Development of Retrieval Method(FY2021-22)]

Matters ofconcern•

Cask cell(cask transfer inspection area)
Waste transfer cell

懸 ・・ Need
開口部表面仕上げ要否
for finishing the surface of the opening
念 (Considering
the impact on cell adapter installation)（セルアダプタ設置への影響考慮）
事 ・Specifications of the temporary cell for the work of making
・ 開口作業用仮セル仕様及び開口時のダスト対策
項 an opening and dust measures once the opening is made・Methodof removing the X-6 penetration and contamination
・ X-6 ペネ撤去工法及び汚染管理
control

Cell downsizing
Fuel debris retrieval equipment installation work steps©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]

No.30① Installation of large heavy structures(2) Background and purpose of this research✓
Reasons for this research• Studies have been conducted on the equipment for accessing the inside of the PCV pedestal, cell adapter forconnection to the PCV and for confinement, and access equipment composed of the shielding door and cell, withrespect to the side access method, in order to further increase the retrieval scale of fuel debris and reaction internal
structures. In FY2020-21, the access equipment was studied in terms of downsizing the cells to be installed inside theR/B, method of supporting the load of the heavy cells, as also the work steps involved in installing the fuel debris
retrieval equipment.
• The following requirements concerning the access equipment are addressed in this subsidy project.
➢ In order to install the cell structure, which is a large heavy structure, on the PCV connection part, the cell structureneeds to be positioned accurately on the PCV connection part while keeping within the load limit for the floor inside
the R/B, and the connection to the PCV opening needs to be accomplished remotely via the structure equippedwith confinement function and a function for dealing with displacement caused by earthquakes, and the structuresand requirements to accomplish this need to be clearly specified.
➢ As the pedestal opening cannot be modified and changed easily, while connecting the X-6 penetration, which is
the location where the access equipment is installed, to the PCV opening, the mutual correlation between thelocations of both openings (the axis joining the openings) is sufficiently considered, and the access equipment isinstalled along the axis leading to the pedestal opening from the X-6 penetration. Hence for remotely installing thecell structure, the procedures for carrying-in the cell structure and installing it accurately, while meeting theserequirements, need to be established.
• Therefore, in order to install the access equipment accurately inside the R/B, ensuring installation accuracy andoptimization of installation work need to be studied and related development needs to be carried out with respect to thecell structure and connection with the PCV.
✓

Expected outcome of this research, reflection destination, and contribution of the outcome• Expected outcome: Development of the procedures for installing the access equipment, and establishment of therequired specifications of the equipment for remote operation.
• Reflection destination and contribution of the outcome: Establishment of the method for installing the accessequipment inside the R/B for the side access method.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]① Installation of large heavy structures

No.31(3) Project Goals✓
Requirements from the reflection destination• The access equipment is planned to enter from the pedestal opening of the PCV and retrieve fueldebris.
• An access route for the above-mentioned access equipment needs to be constructed in a straightline from the pedestal opening to the X-6 penetration.
• Hence, the shielding door or the cells, etc. which are large heavy structures, need to be installedaccurately along that straight line.
• Also, the connection part between the cells installed on the first floor of the R/B and the PCV
should use a cell adapter with a bellows structure to absorb the displacement in the event of anearthquake.
• Further, the cell adapter, shielding door and the cells need to have a confinement function.
• And, as BSW is installed after the opening is created, it means that the work of installing the cell
adapter will have to be carried out under high radiation environment from the PCV. Henceinstallation by remote operation becomes necessary.
✓ Goals based on the above-mentioned requirements• Studying the required fitting accuracy, adjustment method, etc. and substantiating the structure, in
addition to functions such as the earthquake displacement absorption function, confinement
function, etc. that are required of the access equipment which comprises large heavy structures.
• Detailing the procedures for installing the access equipment.
• Examining the installation procedures that must be verified, and verifying them by element tests.
• Organizing the required specifications of the equipment for remote installation, based on the
results of element tests.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for
Installing Access Equipment]

No.32① Installation of large heavy structures(4) Development schedule[Legend] Planned:
FY2021

Actual:FY2022

Study items
4
Major milestones

5

6

7

8

9

10

11

12

1

2

3

4

5

6

7

8

Interim Report▼

Interim Report
▼

9

10

11

12

Interim Report
▼

1

2

3

Final report▼

Substantiation of the work carried out inside the fueldebris retrieval cell(a) Detailed study of
installation
the structure of the Substantiation of theRequired
work
carried out insideaccuracy
the fuel debris retrieval
cellaccess equipment
Detailed
examination of
structure

Required installation
accuracy Organization of installation
IDR conditions(Structure of the(b) Study on detailingof procedures for
installing the accessequipment(c) Verification ofelement tests for the
installation
procedures(d) Detailing of thework carried out
inside the cells of thefuel debris retrieval
equipment

access equipment)

Detailing of installation procedures
Detailed examinationof structure
Assumption of failuremode of thecomponents

Review as appropriate

Substantiation of installation equipment andtools
Substantiation of installation procedures

Under
review
Risk assessment /Study of response

Study of element test plan

Manufacturing of element test equipment
Preparation forelement tests

Organization of installation
conditions
Detailing of installation procedures
Substantiation of remote installation equipment andSubstantiation of the work carried out inside and outside the fuel debris retrieval
tools
cell andinstallation
study on cell structure
Substantiation of installation procedures
Element test plan (brief study) Element test plan (detailed study)

Element test

Assumption of failure mode of the components

IDR (Element test plan)

Risk assessment / Study of response

Manufacturing of element test equipment Preparationfor element
tests(e) Creation of a reporton installation of large
heavy structures

Element test
Creation of reportCreation of report

Remarks©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for
Installing Access Equipment]

No.33① Installation of large heavy structures(5) Implementation items, their mutual correlation, and correlation with other research✓
Implementation items and correlation between the implementation items
a. Detailed study of the structure of the access equipment•
Substantiation of the specifications of the access equipment and clear
specification of installation requirements<Brief explanation>b. Study on detailing of procedures for installing the accessequipment•
Detailing of installation procedures•
Substantiation of installation tools

c. Verification of element tests for the installation procedures•
Designing and manufacturing of equipment for the element test•
Identification of issues in implementation of element tests and in thespecifications of the equipment for remote installationc. Verification of element tests for the installation procedures•
Identification of required specifications of the equipment based on the
results of element tests

d. Detailing of the work carried out inside the fuel debris
retrieval equipment cell•
Detailing of installation procedures•
Substantiation of installation tools(Detailed explanation)

Verification by mock-up tests after completing basic designing(1/1 scale)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.34① Installation of large heavy structures(5) Implementation items, their mutual correlation, and correlation with other research✓
Implementation items and correlation between the implementation items： Items targeted during the installation oflarge structures in FY2021-2022
Work
step

Removal of interfering objects inside theReactor Building(Removal of RHR piping, etc.)

Ground preparation in front of R/B

Removal of BSW in front of air lockand around X-6 penetration：Items studied particularly in
FY2021-2022
Making of an opening in the R/B buildingwall⓪ Current state
Laid iron plate
TrenchG/H

Crushed stone

TP+8,900

IndoorOpening for entry ofworkers

Existing ground

Outdoor① Digging down TP+8,900-300mm

Illustration ofwork steps

Digging down

Building opening for fuel debris
retrieval cell

TP+8,900

G/H

Crushed stone Existing ground② Ground preparation using concrete

Scope of ground
preparation

Ground preparation
using concrete

TP+8,900

RemarksWork
step

Crushed stone

Building opening for themini cask cell

G/H

G/H

Existing ground• FY2019-2020: Implementation of conceptual
study on the method• FY2019-2020: Implementation of conceptual
study on the method

Shielding door base plate

Setting up the outdoor yard

Setting up the cell installation frame

Shielding door installation
Anchor casting area
Base plate for the rail

Cell installation frame• FY2017-2020: Implementation of conceptual
study on the method

Making a hole in the BSW/Cutting the X-6
penetration
Shielding door

TemporaryshieldingG/H

Shielding door

Base plate for the rail
Retractable
part

Illustration ofwork steps

Base plate

Motor 電動フォーク
operated fork

① Installation of base plate

G/H

Truck

Installation
cart

Remarks

電動フォーク
Motor
operated fork

Craneoutdoor
for carrying-in/out
Overhead retractableyard

Illustration of outdoor yard
(Overhead retractable tent
house)

X-6 penetration cutting② Installation of rail

PCV Penetration plug

Closing plate(Further, the penetration is closed beforehand)

Shielding door

• FY2017-2020: Implementation of conceptual
study on the method• FY2021-2022: Implementation of study on
substantiation of the structure of the baseplate and shielding door, and on detailing of
the installation method

Penetration plug

Cutting• FY2019-2020: Implementation of conceptual
study on the method• FY2021-2022: Implementation of study on themethod of marking the reference line for
installation

Core boring• FY2017-2018: Plan to use the method ofmaking a hole in BSW developed by Toshiba(hole making method)• FY2021-2022: Implementation of study on themethod of ascertaining the shape of the PCV
steel plate through measurements using 3D
scanner©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.35(5) Implementation items, their mutual correlation, and correlation with other research✓
Implementation items and correlation between the implementation items： Items targeted during the installation oflarge structures in FY2021-2022

Work
step

Carrying-in and installation of cell adapter

Pressure resistance test and trial run of thecell functions

Arm introduction and making of hole in PCV wall

Shielding door closed

Robot arm for welding

Cell adapter
grabbing arm

Installation of fuel debris retrieval cell andother structures：Items studied particularly in
FY2021-2022

Fuel debris retrieval cell
PCV concrete wall

Carrying-in of thetelescopic dual arm

Fuel debris retrieval cell

Weldingequipment
and tool rack

Mini cask cell
Fuel debris retrieval back-up cell

Maintenance cell
Canister cell

Shieldingdoor

Illustration ofwork steps

Configurationof the boundary
バウンダリの構成

Cell adapter
Cell adaptertransportation cart

Debris transportation
container cell

Crawler craneWelding
溶接個所
locationPush jack

LLW transportation
container cell

Tent house

RemarksWork
step• FY2019-2020: Implementation of conceptual
study on the method• FY2021-2022: Cell adapter installation method,interfering objects verification and identificationof required specifications for the installationequipment• FY2019-2020: Implementation of conceptual
study on the method• FY2021-2022: Overall structural verification(structural verification of boundary) using
simulated bodies• FY2017-2020: Implementation of conceptual study
on the method

Removal of interfering objects outside the pedestal (1)(Telescopic dual arm type robot)

Removal of interfering objects outside the pedestal (2)(Telescopic dual arm type robot)

Removal of interfering objects from inside thepedestal (1)(Telescopic dual arm type robot)

Removal of interfering objects from inside the pedestal(2)(Telescopic dual arm type robot)• FY2017-2020: Implementation of conceptual
study on the method• FY2021-2022: Verification of cutting
performance of the tip tool, and development of
the function for automatically avoiding
obstacles• FY2017-2020: Implementation of conceptual
study on the method• FY2021-2022: Verification of cutting performanceof the tip tool, and development of the function
for automatically avoiding obstacles• FY2017-2020: Implementation of conceptual
study on the method• FY2021-2022: Verification of cutting
performance of the tip tool, and development of
the function for automatically avoiding obstacles• FY2017-2020: Implementation of conceptual
study on the method• FY2021-2022: Verification of cutting performanceof the tip tool, and development of the function
for automatically avoiding obstacles

Illustration ofwork steps

Remarks©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.36(5) Implementation items, their mutual correlation, and correlation with other research✓
Implementation items and correlation between the implementation items： Items targeted during the installation of large
structures in FY2021-2022

Work
step

Installation of fixed-type rail
(Fixed rail type dual arms)

Removal of interfering objects frominside the pedestal (3)(Fixed rail type dual arms)

Illustrationofwork steps

Fuel debris retrieval(Fixed rail type dual arm type robot)

Constant
monitoring
Sub-criticality
measurement• FY2017-2020: Implementation ofconceptual study on the method

RemarksWork
step

Sub-criticality measurement：Items studied particularly in
FY2021-2022

Fuel debris transfer• FY2017-2020: Implementation of conceptual
study on the method• FY2021-2022: Verification of cutting
performance of the tip tool, and developmentof the function for automatically avoiding
obstacles

Fuel debris retrieval(Hydraulic arms)• FY2017-2020: Implementation of conceptual
study on the method

CRD removal• FY2017-2020: Implementation of conceptual
study on the method

Fuel debris delivery

Unit canCanister cell

Transport
ation cart

Illustrationofwork steps

Fuel debris
retrieval cell

Unit canWinch

Fuel debris
transportation cask cell

• FY2017-2020: Implementation ofconceptual study on the method

Remarks• FY2017-2020: Implementation of conceptual
study on the method• FY2021-2022: Verification of cutting
performance of the tip tool, and developmentof the function for automatically avoiding
obstacles• FY2017-2020: Implementation ofconceptual study on the method

Mini cask cell

• FY2019-2020: Implementation ofconceptual study on the method©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.37① Installation of large heavy structures(6) Implementation items(6)-1: a. Detailed study of the structure of the access equipment✓ Objective• In order to install the cell structure, which is a large heavy structure, on the PCV connection part, the cellstructure needs to be positioned accurately on the PCV connecting part while keeping within the load limit
for the floor inside the R/B, and the connection to the PCV opening needs to be accomplished remotely via
the structure equipped with confinement function and a function for dealing with displacement caused byearthquakes. The structures and requirements to accomplish this need to be clearly specified.
• The access equipment that is provided with a confinement function, etc. and conforms with the limitations on
the floor load applicable to fuel debris retrieval equipment using the side access method, needs to be
substantiated.
✓ Project Goals• To substantiate the structure of the cell adapter, shielding door and cell that form the access equipment.
• To study the specifications of the confinement function and the earthquake displacement absorptionfunction, and the structure.
• Also, to add the required installation accuracy and method of adjusting the position while installing, to thestructural study.
✓ Comparison with existing technologies• The cell adapter, shielding door and cell that are the components of the access equipment are technologies
that are present in existing nuclear facilities.
• Since the access equipment, which comprises large and heavy structures, has to be installed accurately
inside the existing R/B at the Fukushima Daiichi Nuclear Power Station, and the cell adapter has to beinstalled by remote operation, the requirements of the installation equipment need to be satisfied.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.38① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results

1) Connection structure of the boundary with the PCV (1/7)➢➢➢➢

A base plate is installed to support the load of the BSW and then the shielding door is installed.
The cell adapter is welded between the PCV and the shielding door.
The shielding door and the fuel debris retrieval cell are welded/connected with bolts.
The confinement boundary comprises the fuel debris retrieval cell, shielding door (casing) and the cell adapter.
Base plate

Base plate

BSW

Shielding door
(Casing)
Shieldingdoor

Cell adapter

Connecting
flangeWelding(Remote operation)

PCV

Shieldingdoor

Shieldingdoor[Illustration of the shielding
door installation][Mass of each component]・ Cell adapter: 3 ton
・ Base plate: 70 ton
・ Shielding door: 25 ton
・ Fuel debris retrieval cell: 140 ton
・ Equipment inside the cell/ancillaryequipment (including the margin): 42ton

Welding(Remoteoperation)

Cell adapter

Welding(Remoteoperation)

Welding
locations(Inside the cell)
Fuel debris retrieval cell

Bolt connection
location(Outside the cell)[Connection methods]
Fuel debris
retrieval cell

[Confinement boundary]©International Research Institute for Nuclear DecommissioningNo.39

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures: Load mass point(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results

1) Connection structure of the boundary with the PCV (2/7)[Shielding door]
Cell installation frame and anchor casting part(enlarged view)
Fuel debris retrieval cell

(Concrete opening)

Fixed on the strong members using post installed anchors
Cell installation frame (Enlarged view)

Shielding door

Shielding door

Fuel debris retrieval cell

Cell installation frame(Shielding door)(Shielding door housing)(For anchor M20 for fixing theshielding door frame)

Connecting part of the shielding
door and cell installation frame(Enlarged view)(Shielding door housing)(Shielding door)

X-6 penetration(Concrete opening)(External dimensions of cell adapter)(Internal dimensions of cell adapter)(Concrete opening)(Shielding door housing)(Stroke)(Shielding door)(BSW opening)(External dimensions of cell adapter)(Internal dimensions of cell adapter)(Sipping lag)Fixed rail typedual arms

X-6 penetration

Inner side of bellows©International Research Institute for Nuclear DecommissioningNo.40

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results

1) Connection structure of the boundary with the PCV (3/7)[Boundary part]A structure such that the cell adapter flange part can be hitched on the shielding door
[Carrying-in of cell adapter ①]
Shielding door

BSW

[Carrying-in of cell adapter ②][Cell adapter length
adjustment/temporary fixing/welding]
BSW

BSW

[Opening of PCV]

Fuel debris
retrieval cell

BSW

Positiondetermining pin

Welded part
PCV

Boundary

Cell adapter

X-6 penetration(cut)

Adjusting the length ofthe cell adapter with thehelp of the sipping bolt

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.41(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results

1) Connection structure of the boundary with the PCV (4/7)
The bases for establishing the dimensions of the cell adapter, BSW opening and shielding door are consolidated below.
<Width/Height> ⇒ The size of the BSW opening is established by keeping a 100mm# margin while inserting from an openingthat is required based on the arm and rail size.
No.

Name

Width (mm)

Basis

1

Required opening(Arm and rail)2400

Arm and rail

2

Internal dimensions ofcell adapter

2800

200mm (= sipping lug height
100mm+ margin 100mm) × 2 =
400mm

3

Cell adapter
dimensions

2832

4

BSW opening

3032 ≒ 3100

Height (mm)
2525
225

Basis
Arm and rail
Height from the floor

2925(2525+400)

200mm (= sipping lug height 100mm+ margin 100mm) × 2 = 400mm

Plate thickness 16mm × 2 = 32mm

2957

Plate thickness 16mm × 2 = 32mm

External dimensions + margin
100mm × 2 (= 200mm)

3057

External dimensions + margin 100mm(External dimensions of cell adapter
from the floor +100mm)# The margin is established based on the work of installing large heavy objects by the company in the past.

<Length/Depth> ⇒ Determined by measuring the distance from the PCV steel plate to the shielding door.
No.

Name

Length (mm)Approx. 1780

1

2

Cell adapter

Depth of theshielding door

(In accordance withthe actual
measured value)

800

Basis
Gap between PCV and BSW (44mm), BSW thickness (1676mm), base plate thickness(60mm),

44 + 1676 + 60 = 1780mm
Frame for the fixed rail (350mm), shielding door thickness (285mm), shielding door plate
thickness (45mm, 20mm), total gap (100mm)
350 + 285 + 45 + 20 + 100 = 800mm©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.42① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results
1) Connection structure of the boundary with the PCV (5/7)
Clearance with the shielding door and BSW opening while carrying-in the cell adapter ⇒ Established based on the dimensions required for the
remotely operated welding robot
Gap while installing and inserting(Step 1: Avoiding interfering objects)

When installation is complete(Step 2: Securing a clearance forwelding)

Width

200mm
(100 + 100)

270mm
(135 + 135)

High

200mm
(100 + 100)

270mm
(135 + 135)

Requirements from theremotely operated robot
Welding specimen

Clearance

Flat surface

135

135

Simulated X-6
penetration

Manipulator(Property of IRID)

Illustration of welding in a confined space

135

Welding head

135

Side

135

135

135mm

A clearance of at least 135mm is
required for the welding head to accessthe part to be welded.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.43① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results

1) Connection structure of the boundary with the PCV (6/7)[3D-CAD of boundary structure]

Position determining pin

Shieldingdoor
Fillet welded part

Cell adapter

Inner surface of cell adapter
PCV
X-6
penetration

Fixed rail
installation
platform

Sipping bolt

Bellows

Fuel debris
retrieval cell

[Examples of operating performance of cell adapter (square shaped
bellows) in nuclear facilities]
・ Fast breeder experimental reactor main exhaust duct
・ High-temperature incinerator exhaust gas treatment facility
・ Connection between glove boxes<Sipping bolt>
・Restricts the retraction of bellows
during transportation・Size × number of bolts: M24 x 6
bolts
・Long bolts may be used as well

Fillet welded
part

Cell adapter for element tests(1/2 scale)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.44① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results

1) Connection structure of the boundary with the PCV (7/7)[Design specifications of cell adapter]
№

Items

Unit

Numerical values

1

Size

mm

2800 x 2925

2

Entire length

mm

1500

3

Material

―

SUS

4

Design pressure

kPa

20.0

5

Design temperature

℃

40.0

6

Amount of displacement in the axial
direction (horizontal)

mm

10.0 / -10.0

7

Amount of displacement in the
direction perpendicular to the axis
(vertical)

mm

5.0 / -5.0

8Position determining pin (connecting
hole)

Pins

2 pinsHole for the position
determining pin

It has been confirmed that
deflection due to self weight
does not have an impact.
(Deflection: about 1.5mm)

No. 4
Design pressure➢ The design should be water pressure resistant so that even after the hole is made in the PCV steel plate it can be covered with water as required inorder to ensure reversibility.
➢ The design pressure of the cell adapter is established based on the maximum water head pressure is applied to the cell adapter.
Maximum water head pressure = TP10064 (Current water level) - TP8764(R/B1FL) = 1.3m (0.0127MPa(g) ≒ 0.02MPa(g))

No. 5
Design temperature➢ Established based on the temperature inside PCV
No. 6, 7
Amount of displacement in the axial direction/amount of displacement in the direction perpendicular to the axis
➢ Established as followed based on the documents obtained from TEPCO on February 22, 2022.
(1) Considering the case of 900gal, ±10mm while ensuring sufficient margin as against a maximum horizontal value of 1.2mm.
(2) Vertical value is half that of the horizontal value = ±5mm.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.45① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results
2) Procedures for connecting the boundary with the PCV (Proposed)
Reference line

X-6 penetration

Reference line

① Marking the reference line## The line joining the pedestal opening
and X-6 penetration opening
Connecting the shielding door and cell
adapter: Welding (2 locations)② Installation of base plate③ Installation of shielding door

④ BSW opening(Temporary closure and reduction inlength of X-6 penetration)

Connecting the fuel debris retrieval cell and shielding
door (outside): Bolts
Carrying-in of the telescopic dual arm⑤ Installation of cell adapter(remote operation)⑥ Installation of fuel debris retrieval cell

⑦ Making an opening in PCV

Connecting the fuel debris retrieval celland shielding door (inside) Welding⑧ Laying of fixed rail for
removal of internalinterfering objects©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.46① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results3-1) Study of the strength of the access equipment ～ Distribution of the load on the floor because of the installation stand

➢
➢
➢
➢

The cell weight is 270 ton after streamlining the shield as well.
The structure is such that the weight of the cell does not get distributed directly on the R/B floor, but is supported by strength
members such as the floor beams and wall of the R/B.
Based on the site investigation results, etc., in addition to BSW since the nearby floor is expected to be used as a strength
member as well, the evaluation was revised (：load pivot point /：additional pivot point).
As a result, workability improved and the exposure of the workers reduced as well.

[Structure of the load on the R/B]
PillarReactor Building
Shield

Floor
beams

Installation cell
standReactor
Building wall

Frame structure

Fuel debris
retrieval cell

BSW

＜Additional pivot points＞
PCV©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.47① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results3-2) Study of the strength of the access equipment ～ Evaluation of the anchor bolt for fixing the cell installation frame

Purpose: It was determined that the BSW anchor casting performance needs to be improved from the perspective of reducing
worker exposure.
The shape of the installation stand described in the Accomplishment Report for FY2021*, which had a larger BSW
anchor casting area was modified.
[Case 1: Main Proposal] BSW and floor support proposal➢ The anchor casting area of the cell installation frame should be decentralized from only the BSW to include the BSW, thearea under its floor and some of the floor beams as well.
[Case 2: Additional study] Proposal to support the entire floor surface➢ The extreme case wherein the BSW anchor casting in Case 1 is eliminated should be studied for further reducing exposure.
➢ The anchor casting area of the cell installation frame should be decentralized from only the BSW to include the BSW, thearea under its floor and some of the floor beams as well, and the stand should be reinforced.
Wall surface anchor castingarea (130 bolts)

Wall surface anchor casting (32 bolts)

Wall surface anchor casting (0 bolts)
Area under BSW floor (46 bolts)

1m
Shielding door base plate
Accomplishment Report for FY2021 (*)
Fuel debris retrieval cell structure

Area under BSW floor (48 bolts)

Case 1: Main Proposal[Case 2: Additional study](*) https://irid.or.jp/wp-content/uploads/2022/08/2022007_deburitoridashi.pdf©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.48① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results3-2) Study of the strength of the access equipment ～ Evaluation of the anchor bolt for fixing the cell installation frame
Items

Previously reportedCase 1: Main Proposal[Case 2: Additional study]

BSW wall surface

130 bolts

32 bolts

0 bolts

Area under BSW floor

0 bolts

48 bolts

46 bolts

Cell installation frame
part

277 bolts

148 bolts

62 bolts

Total

407 bolts

228 bolts

108 bolts

BSW wall surface structure

Numberof bolts•

MeritsSimple structure which does not havediagonal bracing for supporting the
BSW wall surface and the building wall
surface•Comparatively larger number of BSW
wall surface anchor casting bolts
Comparatively larger number of overallanchor casting bolts••

Reduced number of BSW wall surface
anchor casting bolts
Reduced number of overall anchor
casting bolts

•
•

•
•
Demerits•

Diagonal bracing is required to support
the cell for seismic resistance or the
rigidity of the cell needs to beenhanced.

•

Reduced number of BSW wall surface
anchor casting bolts
Reduced number of overall anchor
casting bolts
A frame is required to support theshielding door.
Diagonal bracing is required to support
the cell for seismic resistance or the
rigidity of the cell needs to beenhanced.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.49① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results3-3) Study of the strength of the access equipment ～ Evaluation of the strength of the Reactor Building(Brief strength evaluation by modeling the BSW and Reactor Building wall surface openings)➢ Analysis model: A multi-mass model in which the BSW and Reactor Building wall surface openings
required for installing the access equipment are made in a model of the current Unit 3 Reactor Building
and which is provided with heavy load conditions considering side access retrieval method (Buildingground interaction system model).
➢Seismic ground motion: Seismic response analysis is conducted with respect to a seismic ground motionof Ss 900 that is used for the study as a severe value on the safer side.

➢

Seismic response analysis result: It was verified that there is sufficient margin between the shear strain
on the seismic wall (0.19 x 10-3) and the evaluation criteria （4.0×10-3）.
Seismic response
analysis model(Detailed strength evaluation by modeling the openings)➢ Studies were conducted on functional maintenance of the seismic wall of the Reactor
Building with respect to long-term vertical load (self weight) and seismic load using a three
dimensional elasto-plasticity FEM analysis model.
➢

As a result of the evaluation, it was verified that the compressive strain (957μ) of concreteand the tensile strain (673μ) of the rebars is below the evaluation criteria (compressive
strain: 3000μ, tensile strain: 5000μ).

BSW opening

Cross section of
the analysis model

Reactor Building opening

Three dimensional elastoplasticity FEM analysis model©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.50① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (1/7)a) Requirements at the time of installation➢ A route that would enable the robot arm to access the pedestal opening from the X-6 penetration opening in a straightline needs to be established.
➢ In other words, the fixed rail and the rail inside the cells need to be installed along the straight axis joining the pedestal
opening and the X-6 penetration opening.

Reference line for installation

Maintenance cell
Fuel debris retrieval
preparatory cell
Air-tight door
Shielding door

Cell adapter

Pedestal
opening

Rail inside the cells
Fuel debris retrieval cell

X-6 penetration
opening

Fixed rail
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.51① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (2/7)b) Deviation occurred during installation[2] Rotational direction(Direction of angular deviation from a certain line heading towards a center) (Angle of deviation from the reference line)
The greater the distance from the center, larger is the angle of deviation.
→ The extent of deviation can be controlled by positioning the installation reference line and the rail installation positionreference line at a location that is as distant as possible from the center.
[2] Horizontal direction
The extent of deviation during installation can be controlled within the clearance of the pedestal opening and fixed rail.
→ At other sites, for example in the case of the clearance of BSW and cell adapter, there is sufficient margin for deviationand it can thus be dealt with.
Further, deviation in the vertical (height) direction can be adjusted when installing the fixed rail.

Clearance of thepedestal opening andthe fixed rail

Rail installationreference line
Rail installationreference line

Reference line for installation
Reference line for installation[1] Rotational direction[2] Horizontal direction©International Research Institute for Nuclear Decommissioning

No.52

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (3/7)

1°

0.18m

c) Setting the installation accuracy for the rotational direction➢
Set to less than 1°. (Tentatively: apportioned to the horizontal accuracy mentioned below.)

10md) Setting the installation accuracy for the horizontal direction➢ Needs to be installed within the clearance of the pedestal opening and the fixed rail.
➢ Installation accuracy is set as given below.
Pedestal opening: 750mm
Width of fixed rail: 640mm

Clearance 110mm(One side: 55mm)

Installation accuracy:±50mm

PCV steel plate
Cell adapter

Pedestal
opening

Reference line
for installation

BSW

Fixed rail*

Fixed rail
BSW

Pedestal*Unit 5 Field investigation
Pedestal opening width: 760 to 765mm

Fixed rail installation platform

Clearance of the pedestal opening and the fixed rail

Considered almost parallel©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.53

4) Study on required installation accuracy for the accessequipment (4/7)e) Other: Installation accuracy of cell adapter
If the central axis deviates horizontally or vertically during the installationof the cell adapter, its impact on the groove gap is evaluated.
【 Evaluation conditions】
PCV outer diameter = 20,000mm
Cell adapter dimensions = 3,000mm# The center of the cell adapter is assumed to be the center of the
PCV spherical shell.

As the gap with the welding portion needs to be under 5mm,
Installation accuracy of cell adapter: 15mm or less

Amount of increase in groove gap: Δx(mm)(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results

Extent of deviation of central axis from cell adapter L(mm)Amount of increase in groove gap: X(mm)# The installation position of the cell adapter is adjusted so that the gap with the welded portion is under 5mm.
Further, it may be possible to eliminate the gap as required by pressing the cell adapter as well.

Cell adapter
Fillet welding

Extent of deviation of central axis: L(mm)Covering sheet

Cell adapter

Shielding©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.54(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results
Robot arm

4) Study on required installation accuracy for the access equipment (5/7)
Reactor Building

Rail inside the cells

PillarShieldRail inside the cells

Floor beams

Cell installation frame

BSW

Fuel debris retrieval cell

PCV

Frame structure
Fixed rail

Shield(Cell)

Cell installation
frame

Reactor Building wall

Cell installation frame➢ The structure is such that the weight of the cell does not
get distributed directly on the R/B floor, but is supported
by strength members such as the floor beams and wall of
the R/B.

Shield (cell)➢ Method of fixing the cell installation frame on to theReactor Building floor surface.

Shim for adjusting
the height
Base plate

Building
wall

Beam

Pivot point of the loadNote: Anchor casting into the floor
surface is considered- The base plate is installed on the Reactor Building floor
surface- The cell installation frame is welded and fixed on to thebase plate(The height is adjusted with the shim plate)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.55(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (5/7) - Installation method
BSW

Shielding door casing
Shielding door

Installation accuracy

Cell reference line

Building for the rotationalpillardirection⇒Less than 1°

Cell adapter

Installation accuracy for thehorizontal direction⇒ Less than ±55mm
640/750

Fixed rail
Fuel debris retrieval
preparatory cell

Fuel debris retrieval cell

Positiondetermining pin(BSW opening)(External dimensions of cell adapter)(Internal dimensions of cell adapter)(Concrete opening)(Internal dimensions of cell adapter)(External dimensions of cell adapter)

Referenceline forinstallation① The central axis is established byleaving a gap of 55mm on the left andright sides to make room for the large
hydraulic arm* to pass.
② The “required opening size” is established by leaving amargin of 100mm on the left and right sides in accordance withthe telescopic type guiding equipment* or the fixed rail thatpasses through, whichever is wider.

(Sipping lag)Fixed rail typedual arms

X-6 penetration

Pedestal③ The outer diameter of the cell adapter is establishedconsidering the unevenness* of the bellows in addition to
the “required opening size”.
Inner side of bellows(Telescopic type guiding equipment)④ The “BSW opening width” is established by considering
the unevenness* of the core in addition to the outer
diameter of the cell adapter.

[There is room for modifying the size of the BSW opening part.
Also, changes can be made by modifying the dimensions of “*”.]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (5/7) - Installation method

No.56① The cell reference line and alignment of the cell andthe shielding door casing is verified at the plant.*② The shielding door casing is installed in accordance with thereference line for installation.*

Shielding door
casing③ The cell installation frame (rail) is installed based on thereference line for installation.*

BSW(Seal welding from the inside after installing the cell*)

Building
pillarCell reference line

Cell adapter

640/750
Fixed rail
Fuel debris retrieval
preparatory cell

Fuel debris
retrieval cell

Reference line
for installation

Pedestal

Position determining pin④ The distance, etc. up to the position
determining pin and the PCV is measured and thecell adapter is adjusted.*⑤ Cell adapter is installed
remotely.
Shielding door

Cell adaptertransportation cart

Part where guideholes are made[*: Can be implemented manually using the shielding door, etc.]

Rail for transportation

Cell adapter

Illustration of cell adaptertransportation work

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.57(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (5/7) - Installation method(Illustration of actual dimensions)

BSW

Shielding door
casingBuilding pillar Shielding door
Cell installation frame
Cell reference line

Installation accuracy for thehorizontal direction⇒ Less than ±55mm

PCV steel plate
Cell adapter

640/750

Fixed rail

Pedestal
Fuel debris retrieval cell
Referenceline forinstallation

Shieldingdoor

Biologicalshielding wall
PCV steel plate

160

Installation accuracy
for the rotational
direction⇒Less than 1°

Pedestal
Cell adapter

Fixed rail
Retrieval arm©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.58① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (6/7)f) Other: Actions to be taken in the event of an earthquake during installation

Even through the duration of installation is about 1 year, which is short, earthquakes are likely to occur during work.
Actions to be taken in the worst case that an earthquake should occur, are listed here.

[1] Maintenance of confinement function➢ The work of making an opening in the PCV wall surface is carried out by means of a robot arm, while maintaining
negative pressure inside, after conducting the pressure resistance test once the installation of access equipment(cells) is completed.
Hence, even if an earthquake occurs during the work of making an opening, a boundary is secured by means of
PCV - cell adapter - shielding door - cell.
➢ During the work of making an opening in the BSW or the outer wall of the Reactor Building, G/H is installed as ameasure to prevent dispersion of dust produced during the work into the surroundings.
[2] Actions to be taken in response to deviation in the installation position caused by the earthquake➢ In the event of a major earthquake, it is confirmed if there is any deviation from the coordinates that are set formarking the installation reference line and the reference points* that are marked on the R/B and PCV.
*: If X-6 penetration is present, X-6 is the reference point.
: When the X-6 penetration is removed, new reference points are marked on the R/B and PCV.
➢ If there are any deviations, the installation reference line is set again and the installation position is adjusted
accordingly.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.59① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (7/7)g) Summary (1/2)

1 Required installation accuracy
1) Cell installation accuracy① Within 1° in the rotational direction, within ±50mm in the horizontal direction with respect to thereference line

2) Cell adapter① Within ±15mm from the installation reference line
3) Actions to be taken in the event of an earthquake during installation① Confirming for deviation from the installation reference line and the reference points marked on
the R/B and PCV
2 Structure formation
1) Establishment of the boundary from PCV - cell adapter - shielding door casing - cells① Verification of viability including that of installing the casing, work in confined spaces, andwelding work
② Indication of specifications for the equipment for remote operation (Mentioned in No. 116)

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.60① Installation of large heavy structures(6) Implementation items (6)-1: a. Detailed study of the structure of the access equipment✓ Implementation items and results4) Study on required installation accuracy for the access equipment (7/7)

Shielding doorg) Summary (2/2)

3 Plan pertaining to the installation method[1] The reference line for installation joining the pedestal opening and
the X-6 penetration opening will be established .
[2] The rail installation position reference line will be established on thecell (including the shielding door, etc.) after the cell is built at theplant.
[3] The cell will be installed where the rail installation position referenceline coincides with the reference line for installation.
[Reactor Building][Plant]Fuel debris
retrieval cellRail installation reference line

[Reactor Building]Shielding door
Fuel debris retrieval cell

X-6 penetration

Rail installationreference line

Reference line for
installation

Reference line
for installation
PedestalRail inside the cells[1] Establishing the reference line for
installation

Rail installationreference line

[2] Establishing the rail installation reference line

[3] The cell will be installed where the rail
installation position reference line coincides withthe reference line for installation.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.61① Installation of large heavy structures(6) Implementation items(6)-1: a. Detailed study of the structure of the access equipment✓ Contribution of the results towards the reflection destination• Specific access equipment for establishing the access route for retrieving fuel debris present inside the pedestal
opening can be provided for fuel debris retrieval equipment used in the side access method.
• The access equipment can be equipped with a confinement function and the function of absorbing displacementsin the event of an earthquake.
• The method of installing the cell adapter by remote operation can be established in order to reduce the exposureof workers during installation.
✓ Analysis from the viewpoint of on-site applicability• As the cell adapter has to be installed under high radiation environment from the PCV after the opening in the
BSW is made, installation (dimensions, required accuracy) by means of equipment for remote operation isconsidered. (Reference: No. 35 to 40, 42)• A structure that requires minimal on-site welding work is used. (Reference: No. 35 to 42)• Closing the shielding door in accordance with the work procedures, etc. after the opening in the BSW is made, isconsidered for reducing worker exposure. Further, considering the rare possibility that this gets reversed, astructure that enables complete sealing by installing a closing plate on the shielding door is used.
(Reference: No. 35, 36)✓ Issues• For the shielding door or the cells, the base plate is planned to be installed on the BSW using post installedanchors. The structure of the fixed part of the base plate needs to be studied and determined upon conductingsite investigation, confirming the status of the arrangement of reinforcement bars, and considering theirplacement.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.62① Installation of large heavy structures(6) Implementation items(6)-1: a. Detailed study of the structure of the access equipment✓ Level of achievement compared to the goals• The specifications and structure of the access equipment with confinement function and displacement
absorption function for dealing with an earthquake, were substantiated. (Reference: No. 35 to 40, 42)• As part of the substantiation mentioned above, the installation accuracy and adjustment method during
installation were studied and the results were reflected in the structure.
✓ Future plans• In order to make it more feasible, results of verification by element tests will be provided as feedback andthe specifications and structure of the access equipment will be revised accordingly.
• The impact of dust dispersion when the opening in the BSW is made will be studied.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.63① Installation of large heavy structures(6) Implementation items(6)-2: b. Study on detailing of procedures for installing the access equipment[Purpose]: Verification of feasibility of the side access method for large scale fuel debris retrieval based on on-site
application.
[Objective]: Detailing of procedures for installing the access equipment related to fuel debris retrieval
Study of the method of identification and resolution of issues in implementing the procedures✓ Comparison with existing technologies
・ The “existing technologies” are used or combined for the installation method.
Along with using general technologies and results of past research, practical studies are conducted while comparing
with the environment (reduction in personnel exposure, prevention of spread of contamination, dust reduction, etc.)
specific to the stabilization of Fukushima.

✓ Implementation items and results
・ Studies on the method and detailing of procedures concerning installation of access equipment (shielding door, cell
adapter, large cells) installed inside the R/B.
[Results]: ① Detailing of the overall procedures concerning the access equipment (installation steps)② Detailing of installation procedures of the cell adapter, which are believed to be technically highly difficult(installation steps)③ Clear specification of the method of identification and resolution of issues in the installation procedures©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.64① Installation of large heavy structures(6) Implementation items (6)-2: b. Study on detailing of procedures for installing the access equipment[Result]: Overall step diagram
1. Work of ground preparation outside the R/B

3. Removal of BSW in front of air lockand around X-6 penetration

2. Removal of RHR pipes inside the R/B

Local exhaust
ventilation system

RHR pipe

Conceptual drawing

Equipment
carrying-in
route

Groundpreparation area

Western street
Inside R/B

Laid iron plate

Inside R/B

Ground preparation
using concrete
G/H

Crushedstone▽OP10.2m▽TP9.4m

Sheet covering

RHR pipe

G/H

Wire saw▽OP10.2m ▽TP8.9m

Cutting
location
Existing ground

Current state of theoutdoor area

Crushedstone

In front of personnel
access lock

Workers enter from the access lock
Step (1): Removal of BSW

G/H

Workers enter fromthe access lock

Local exhaust
ventilation system

Sheetcovering

Cutting
location

Existing
groundAfter ground
preparation work

Illustration ofisolation room

Illustration of cutting
the RHR pipes

Step (2): Installation of temporary shielding

Procedure
Issues

The embankment in the area on the west side outside theR/B is flattened so that its floor level is the same as thefloor of the R/B.
・ Inside R/B： TP.8.9m
・ Outside R/B： TP.9.4m ⇒ TP.8.9m

After the dose around the RHR pipes and the residualmaterial inside the pipes is verified, the shielding
material and support are removed.
G/H is installed for cutting the pipes, a pipe balloon plugis installed on both sides of the section of the pipes to be
removed, and after a blowing agent is filled, the pipes
are cut and the opening is closed.

The shield wall around the X-6 penetration and the BSW
in front of the personnel access lock and on the western
passageway are removed using an electric crane, and atemporary shield is installed in front of the personnel
access lock. Thereafter, 3D measurement of the form of
the surface of the BSW is performed.

If there are any objects to be buried, burying thoseobjects, etc.

Dust control measures during work
Method of filling the blowing agent while cutting the RHR
pipes, etc.

Method of removing the BSW in front of the personal
access lock (remotely operated heavy machinery)
Substantiation of additional temporary shielding©International Research Institute for Nuclear DecommissioningNo.65

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-2: b. Study on detailing of procedures for installing the access equipment: Target to bestudied this time

[Result]: Overall step diagram
Issue: Layout marking accuracy
4. Making an opening in the R/B wall

5. Centering (reference line for installation) and layout
marking inside and outside the building

Issue: Substantiation of the structure
6. Installation of shielding door base plate

Building frame (Blue color)

Shielding door base plate

Opening for entry of workers

Base line (reference)

Temporary shield

Building opening for fuel debris retrieval

Conceptual drawing

Electric shutter

Simple tent house

Building opening for mini cask cell

Building opening for fueldebris retrieval

Center of the cell
installation frame

Cart for installation

Area for anchor
placement

Illustration of layout marking inside R/B

Indoor Outdoor
Reference line for installation

Shielding door base plate

Building opening for mini cask cell

Simple tent house

Illustration of the layout
marking outside the R/B

Illustration of the shielding
door base installation

Procedure
IssuesIndoor G/H, vinyl covering, simple outdoor tent house are
installed as dispersion prevention measures, measures toprevent exposure (temporary shielding installation) aretaken and then openings are made in the building wall at 3
locations using a wire saw.

After marking the locations on the BSW (opening) inside theR/B, the installation location of shielding door base plate,
and the location for laying the cell installation frame, etc., themarkings are extended on the floor of the outdoor yard.

After searching for the rebars, the shielding door base plateis fixed by placing anchors.

・ Structure of the greenhouse
・ Dispersion prevention measures while making openings

・ Method of ascertaining the reference location for
installation
・ Floor surface level adjustment method (required accuracy)

・ Handling of objects to be burried (rebars, etc.)
・ Study of transportation and installation methods©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.66(6) Implementation items (6)-2: b. Study on detailing of procedures for installing the access equipment[Result]: Overall step diagram
issue: Study of installation methods
7. Shielding door installation: Target to bestudied this timeIssue: Layout marking accuracy
8. Laying of the cell installation frame

Shielding door frame/shielding
door

Cell installation frame

Installation cart

9. Installation of outdoor tent house

No interference withthe pillars(Unit 5 Field investigation
result)Base plate

Conceptual drawing

Electric fork

Arrangement of the rail
within the building
Reference line
for installation
Cell installation frame
Base plate
Illustration of the shielding
door installation

Arrangement of the rail
outside the building

Outdoor tent house

Procedure
Issues

The shielding door frame / shielding door is carried inby means of the installation cart and bolted.

The cell installation frame is installed inside the R/B andthe base plate and the cell installation frame is installedoutside the R/B by means of a crane, etc.After laying thecell installation frame, the work of centering and levelingthe rail is carried out inside and outside the building.

Tent house is installed at the ground preparation
location outside the R/B.
The ancillary facilities and utilities are set up.

・ Substantiation of the transportation, alignment andinstallation method

・ Method of ascertaining the reference location for
installation
・ Cell installation frame connection method
・ Method of fixing the cell installation frame outside theR/B・ Dimensions of the outdoor tent house (required size)©International Research Institute for Nuclear DecommissioningNo.67

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-2: b. Study on detailing of procedures for installing the access equipment: Target to bestudied this time

[Result]: Overall step diagram

Issue: Processes concerning establishment of the boundary

Issue: Dust control
10. Making a hole in the BSW and cutting the X-6 penetration

11. Carrying-in and installation of cell adapter

12. Installation of the device/equipment transfer system cell
Robot arm for welding

Shielding door
Arm for grabbing
cell adapter

Temporary shielding
Greenhouse

Weldingequipment andtool rack

Mini cask cell

Canister cell

Conceptual drawing

Fuel debris
transportation cask cell
Cell adapter
Greenhouse

Cell adaptertransportation cart

PCV concrete wall
Penetration
plug

LLW transportation
cask cell
Air-tight door

Core boring (Example of methodof making an opening)
Penetration
plug

Cutting
Closingplate
X-6
penetration(It is assumed that the penetration plug (seal) is installed after
the internal investigation or after internal 3D measurement.)

Shielding door

Confinementboundary

Shielding wall

Welding
locations

Cell adapter
Fuel debris
retrieval cell

Welding location

Cell adapter

Procedure
Issues

The cell for making the hole is installed, and an opening is made in
the BSW.
Also, the length of the X-6 penetration is reduced and a closing plateis installed.

After carrying out the work of cleaning the PCV wall surface, conducting
3D measurement and making the cell adapter groove, the cell adapter iscarried in by means of the cell adapter transportation cart and installed.
PCV steel plate and the shielding door are welded on to the cell adapter.

After closing the shielding door, the cell is temporarily placed on thecell installation frame with a crawler crane, and then is carried in andjoined (welded).
After the cell is joined, a pressure resistance test of the inside of thecell is conducted.
Similarly all cells are carried in and installed.

・ Tentative cell specifications for the work of making the opening
・ Removal of X-6 penetration and contamination control Note）
・ Measures against outflow of dust into the gap between the BSW
and the PCV・ Reflection of the PCV surface finishing and measurement into
manufacturing
・ Installation of cell adapter by carrying it in remotely(Position determination and detailing of installation method)・ Study of the required equipment specifications in association withuse of equipment for remote operation

・ Cell fixing method

Note: Deliberately crossed out as this is outside the cope of studies conducted in the PJ.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.68① Installation of large heavy structures[Legend](6) Implementation items (6)-2: b. Study on detailing of procedures for installing the access equipment[Result]: Issues in the cell adapter installation procedures and response measures

Element test ①

Overall verification test

Element test ②

Unit 5 Field investigation

Element test ③
Classification into manual operation
Work step

Issue

Method of resolving the issue

Test planand remote operation
Element test

Actual facility

Manual operation

Manual operation

Remarks

1. Advanced preparation(1) Measuring and marking the cell installation location

Establishment of the method of scanning from

• Desk study of the scanning method and marking[Element test ①]

the X-6 penetration location to the CRD opening

technique will be conducted.

• 1/1 scale simulationand the method of making the marking for the• Feasibility of the studied methods will be verified• Ascertaining the coordinates bycells

using simulated bodies.

means of 3D measurement• Status at Unit 5
will be verified(FY2022)

2. Installation of shielding door

Checking of the status of BSW rebars for placing(1) Installing the shielding door base plate

post installed anchors
Strength of BSW is unknown(2) Installing the shielding door

Method of carrying-in, transportation andinstallation of shielding door

(3) Making an opening in the PCV concrete wall andcutting the X-6 penetration① Making an opening in the concrete② Method of cutting x-6 penetration③ Dust behavior when the opening in concrete is
made• It will be confirmed that the rebars are inserted at200mm pitch and the work has been carried out as-

per the manufacturing drawings (Unit 5 Field-

Manual operation• Rebars in Unit 5
will be investigated(FY2022)

investigation)• Desk study--

Manual operation--

Remote operation-① Subsidy projects that have been implemented in
the past are planned to be utilized.

③ Dust behavior is② Desk study will be conducted③ Circumstances will be estimated through analysis

planned to beanalyzed

3. Cell adapter processing(1) Polishing the surface adjoining the PCV wall
surface(2) Performing 3D measurement of the surface
adjoining the PCV wall surface

Study of method of polishing the surface bymeans of remote operation• Desk study(Identification of specifications required for remote--

Remote operation-

Manual operation

Remote operation-

Manual operation

Manual operation-

Manual operation

Manual operation-

Manual operation

Manual operation-

operation)

Study of 3D scanning method for the PCV steel• Desk study will be conducted on the method.

plate with the marking location of the fitting

Feasibility of the studied methods will be verified using [Element test ②]

reference line as a guideline

simulated bodies• 1/2 scale simulation• Ascertaining the form by means of
3D scanning(3)• Manufacturing of simulated cell

Manufacturing the cell adapter
Carrying
out work(4)

at the• The cell adapter will be manufactured on a trial basis
Processing the cell adapter

Advisability of processing the PCV connecting

using the results of the 3D measurement performed inconnecting flange

surface based on the results of 3D measurement(2), feasibility of processing using 3D measurement will

plant
(5)

adapter• Comparative verification with theform in the drawings

be verified.
Connecting the cell adapter andflange©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.69① Installation of large heavy structures[Legend](6) Implementation items (6)-2: b. Study on detailing of procedures for installing the access equipment[Result]: Cell adapter installation procedure

Element test ①

Overall verification test

Element test ②

Unit 5 Field investigation

Element test ③
Classification into manual operation
and remote operation

Work step

Issue

Method of resolving the issue

Test plan

Element test
stage

Remarks
Actual facility
stage

4. Cell adapter connection work

(1) Inserting the cell adapter in the BSW

Interference of shielding door and BSW• Checking for interfering objects by inserting simulated bodies

concrete with the machined surface• Identification of specifications required for remote operation

Manual operation

Remote operation

Manual operation

Remote operation

Manual operation

Remote operation

Manual operation

Remote operation

Manual operation

Remote operation--

Remote operation

-

-

-

Remote operation

-

-

-

Remote operation-

Manual operation

Manual operation--

Remote operation-(2) Aligning, welding and inspecting the cell adapter[Element test ③]• Desk study of the method (position with the help of the guide pin)
① Aligning the cell adapter on the PCV side

Establishment of the method of positioning • Verification of feasibility of the studied methods using simulated
the cell adapter on the PCV steel platebodies• 1/2 scale simulation(Part which will be checked forinterfering objects will be at 1/1• Identification of specifications required for remote operation

scale)• Checking for interfering objects② Aligning the cell adapter on the shielding door

Establishment of the method of positioningside

the cell adapter on the shielding door side

• Desk study of the method (Positioning with the help of the guide• Verification of positioningpin)(Accuracy ±7.5mm or less)• Verification of feasibility of the studied methods using simulated• Verification of gap measurement

bodies• Identification of specifications required for remote operation③ Measuring the gap between the cell adapter andEstablishment of a method of gap• Study using simulated bodies

the PCV surface

measurement by remote operation• Identification of specifications required for remote operation④ Measuring the gap between the cell adapter andEstablishment of a method of gap• Study using simulated bodies

the shielding door frame

measurement by remote operation• Identification of specifications required for remote operation

Establishment of a method of welding the• Desk study

cell adapter and the PCV steel plate by• Identification of specifications required for remote operation

remote operation(Results of existing subsidy projects will be used)⑤ Welding the cell adapter to the PCV wall surface

Establishment of a method of welding the⑥ Welding the cell adapter to the shielding door side cell adapter and the shielding door byremote operation• Desk study• Identification of specifications required for remote operation

5. Cell installation(1) Closing the shielding door

(2) Carrying-in the cell

Establishment of the boundary formationfrom the PCV steel plate to the cell

• Final verification of the boundary formation after carrying- in by[Overall verification test]means of usual methods (TIR roller, etc.) using simulated bodies• 1/2 scale simulation (Cell length(including cell installation frame)

about 2m)

6. Boundary inspection(1) Pressure resistance test

-

-

-

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.70① Installation of large heavy structures(6) Implementation items(6)-2: b. Study on detailing of procedures for installing the access equipment✓

Contribution of the results towards the reflection destination
・ Contributes to substantiation of the procedures for installing access equipment inside the R/B for the side accessmethod.

✓Analysis from the viewpoint of on-site applicability
・ Procedures were studied based on the structures inside Unit 3 Reactor Building, and the methods were studied
considering on-site applicability.
・ Each method required for installation is a combination of general technology and considers on-site applicability to theextent possible.

✓

IssuesWork through the X-6 penetration and work after removing BSW is highly difficult and is carried out under high-doseradiation environment. Hence it is carried out by remote operation (Carrying out the following work, in particular, ischallenging.)

・ Ascertaining the reference location required for installing access equipment and the method of marking the layout.
・ Method of ascertaining the shape of the cell adapter and the PCV steel plate at the time of connection.
・ Method of positioning the cell adapter on the BSW by remote operation.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.71(6) Implementation items(6)-2: b. Study on detailing of procedures for installing the access equipment✓ Level of achievement compared to the goals[Objective]: Detailing of procedures for installing the access equipment related to fuel debris retrieval
Study of the method of identification and resolution of issues in implementing the procedures[Achievement status]① Detailing of the overall procedures concerning the access equipment： Study of all the steps was completed.
The detailed study on the method of establishing the reference line has been completed as well.
② Detailing of installation procedures of the cell adapter, which are believed to be technically highly difficult: The study of procedures for carrying-in and installing the cell adapter has been completed.
③ Clear specification of the method of identification and resolution of issues in the installation procedures: The following issues have been identified in the installation procedures. The methods for resolving
the issues has been clearly specified.
1) Ascertaining the reference location using a laser scanner and the method of marking the layout2) Method of aligning the cell adapter with the PCV steel plate3) Method of remotely checking the position at the time of carrying-in and fitting the cell adapter©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.72(6) Implementation items(6)-3-1: c. Verification of element test for the installation procedures[Purpose]: Verification of feasibility of the side access method for large scale fuel debris retrieval based on on-site
application.
[Objective]： Verification of viability of the following issues identified in (6)-2 by element tests.
And, verification of workability if the operation needs to be performed remotely.
1) Ascertaining the reference location using a laser scanner and the method of marking the layout2) Method of aligning the cell adapter with the PCV steel plate3) Method of remotely checking the position at the time of carrying-in and fitting the cell adapter
Remote operations are not to be performed during the test. The scope of the test is to perform simple
carrying-in and installation and to clearly specify the specifications required of the remotely controlled
equipment.
✓ Comparison with existing technologies
・ The “existing technologies” are used or combined for the installation method.
Along with using general technologies and results of past research, practical studies are conducted while comparing
with the environment (reduction in personnel exposure, prevention of spread of contamination, dust reduction, etc.)
specific to the stabilization of Fukushima.
✓ Implementation items and results
・ Element tests have been conducted concerning the following issues identified in (6)-2 using test pieces and thefeasibility of the method has been verified.
[Results]: ① Element test plan (Completed)② Study of the element test details and test pieces, and arrangement of the test pieces (Completed)③ Implementation of element tests, provision of the results as feedback for the study on detailing of eachmethod (Completed)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.73① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Elemental test plan ①-2 Establishment of the method of marking the reference line for installation(Aim)• The central axis of the pedestal opening and the reference line for installation needs to coincide so that the robot arm can access the pedestal
opening in a straight line.
• Hence the procedure for extending the central axis of the pedestal opening to the floor surface where the cell will be installed will be
substantiated and verification tests will be carried out.
(Expected outcome)• Establishment of the method of marking the reference line for installation (using 3D scanning), verification of the marking accuracy, and points
of improvement.
➢

The R/B wall surface, X-6 penetration, and pedestal opening were measured by 3D scanning to obtain coordinates, and the method for marking
the reference line for cell installation was adopted to verify the following.
•
3D measurement using the 3D scanning procedure studied, and ascertaining of the coordinate position by integrating the measurement
results.
•
Marking of the reference line for installation on the building floor based on the coordinate data, and verification of its accuracy.
⇒ Feasibility of the method for ascertaining the reference line for installation by 3D scanning measurement is verified.

3D
scanning while the back hatch of the isolation
隔離部屋バックハッチを開けた状態で3D計測
chamber is open (Acquisition of Data A pertaining toTarget①, ②)（ターゲット①、②のデータA採取）Closing the back hatch of the isolation chamber, and
隔離部屋バックハッチ閉止し、気密扉解放
releasing
the air-tight door

Simulated BSW(Not essential)

Simulated R/B wall surface

Target ①

3D
scanning while the air-tight door is open
気密扉を開けた状態で３D計測(Acquisition of Data B pertaining to Target ②, ③
and
X-6 penetration)（ターゲット②、③、X-6ペネのデータB採取）Simulated PCV steel plate

3D scanner(Measurement Data E)

Simulated isolationchamber wall
surface

Target ②

Simulated airtight door

3D scanner(Measurement
Data D)

Simulatedpedestal opening

Movingthe 3D scanner up to the area in the vicinity of x-6
3DスキャナをX-6ペネ近傍まで移動し、
penetration, and performing 3D scanning (Acquisition of Data
Cpertaining
to Target ③ and from inside theX-6 penetration)
3D計測（ターゲット③、X-6ペネ内のデータC採取）Insertingthe 3D scanner inside x-6 penetration, and
3DスキャナをX-6ペネ内に挿入し、performing 3D scanning (Acquisition of Data D frominsidethe X-6
penetration)
3D計測（X-6ペネ内のデータD採取）Insertingthe scanner inside PCV, and performing 3D
スキャナPCV内へ挿入し、PCV内にて３D計測
scanning inside PCV (Acquisition of Data E pertaining
to（X-6ペネ、ペデスタル開口部のX-6 penetration and the pedestal opening
part) ）
データE採取Isolationchamber backhatch(simulated)

The relationship between the R/B wall surface, x-6 penetration and pedestal opening part is ascertained in
計測データA～EによりR/B壁面、X-6ペネ、ペデスタル開口部の関係を座標上で把握し、
terms
of coordinates based on the measurement Data A to E, and the reference line for installation is marked
on
the R/B floor after the isolation chamber is removed (for verifying accuracy)
隔離部屋撤去後のR/B床面に据付基準線をマーキング（精度確認）

Target ③
3D scanner(Measurement Data
A, B)

3D scanner(Measurement
Data C)

3Dスキャン計測イメージ
Illustrationof 3D scanning

Simulated inclined rail for
CRD exchange
Simulated X-6
penetration[Supplement]• It is assumed that the isolation chamber is set up based on
the assumption that measurement can be performed during the“Detailed Investigation Inside PCV” in Unit 3.
• 1/1 scale simulation• 3D scanner is the type equipped with a laser tracker©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.74① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-2 Establishment of the method of marking the reference line for installation
・ Verification of marking accuracy① The line extending from the central axis of the simulated pedestal opening is marked on the floor.
Reference line for installation based on simulated bodies

X-6 penetration
flangePedestal opening

CRD rail (simulated bymeans of scaffolding, etc.)② The 3D measurement Data A - E are integrated and the coordinates of the line extending from the central
axis of the pedestal are obtained based on the measured data.
③ With the Target ① and X-6 penetration flange as the reference points, the line extending from ① ismarked on the floor.

X-6 penetration
flangeReference line for installation based on measured data

Pedestal opening

Marking using the laser marking instrument

CRD rail (simulated bymeans of scaffolding, etc.)
Target ①④ The reference line for installation of ② and ③ are compared and the marking accuracy isverified based on the measured data.
X-6 penetration
flangePedestal opening[Approach towards accuracy verification]
The actual value is verified considering whether or
not the reference line for installation is within the
installation accuracy (±50mm) required for thepedestal opening as the primary condition.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.75① Installation of large heavy structuresExce(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-2 Establishment of the method of marking the reference line for installation
・Time of implementation： Mid October 2022 onwards (Tests completed)・Location: In the premises of the Mitsubishi Heavy Industries, Kobe Shipyard・ Test piece： 1/1 scale

Simulated isolationchamber back hatch(Partition)
Simulated Reactor
Building wall surface(Partition)

Simulated isolationchamber wall surface

Simulated airtight door
(Partition)
Simulated Reactor
Building floor

Simulated PCV
steel plate(Partition)
Simulated X-6
penetration

Some simulated
interfering objects(simulated with the help ofscaffolding, etc.)

3D scanner temporarystorage platform(simulated scaffolding
material)

CRD rail (simulated with thehelp of scaffolding, etc.)

Approx. 19000mm

Approx. 5900mm

Pedestal opening

Approx.
900mm

Illustration of the test piece (Total length approx. 26m * width approx. 2.5m * height approx. 2.5m）©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.76① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-2 Establishment of themethod of marking the reference line for installation

Simulated pedestal opening
3D scanner

Simulated X-6 penetration

Simulated isolationchamber wall

Target ①

3D scanner

Simulated Reactor Building
wall surface

Target ②
Simulated rail for CRD exchange
Simulated pedestal opening

Simulated Reactor Building wall surface

Illustration of the test piece (Total length approx. 26m *width approx. 2.5m * height approx. 2.5m)

Simulated X-6 penetration

Simulated isolation chamber wall
Simulated X-6 penetration

Simulated Reactor
building wall surface

Simulated pedestal opening<<Reference>> 3D measurement output
Verification of the accuracy of the reference line for installation obtained from this data

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.77① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation

・ Method of integrating the measured data A - E
The Measured data A - E is integrated by overlapping each 3D measurement data using common measurement targets.
・ Measured data A, B are integrated using Target
Target②②⇒

Integrated data ①

・ Measured data B, C are integrated using Target
Target③③andandX-6X-6penetration
penetrationflange
flange⇒Integrated data ②

・ Measured data C, D are integrated using the inside
Insideofofthe
theX-6X-6penetration
penetration⇒

Integrated data ③

Measured
計測データ
data

Measurementtarget (○: Relevant part)
計測対象（〇：該当部）
Target ①
ターゲット①

ターゲット②
Target ②

〇

〇

A
B

ターゲット③
Target ③

X-6 penetration
X-6ペネフランジ
flange

〇

〇

〇

〇

〇

C

E

(PCV side)〇（PCV側）・ Integrated data ② and ③ are integrated using Measured
measured data C ⇒Integrated data ⑤

合成元計測データ
Source measured
data to be integrated

data

A

B

①

〇

〇

③

(RB side)〇（RB側）(RB/PCV side)〇（RB/PCV側）

Integrated data ④②

Pedestal opening
ペデスタル開口D・ Integrated data ① and ② are integrated using Measured
measured data
data B
B⇒

Integrated
合成データ

Insideof the X-6
X-6ペネ内部
penetration

〇

C

D

E

〇
〇

〇

〇

Integrated
合成データ

Integrated data ④ and ⑤ are
integrated using integrated data ② andhereby the integration of measured
data A-E is complete.

Source measured data to be
合成元合成データ
integrated

data

①

②

④

〇

〇

⑤

〇

〇

③

〇

The correlation between the central axis of
the pedestal opening and Target ① isaccomplished.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.78① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation〇 Test method0) The test piece is set, the center of the pedestal opening is marked, and the line is extended.
A

C

B

D
E

Simulated Reactor Building

Simulated isolation chamber back hatch

Simulated isolation chamber

End of the X-6 penetrationon the PCV side

X-penetration flange

CRD rail

Inside of the pedestal opening③①②
Line at the center of thepedestal opening

Line extending from the center ofthe pedestal opening
Approx. 19000m

Regi
on
A

B
C
D
E

Approx. 5900m

Measurement section
Target ①

Approx.
900m

T③

T②

T③

T②

X-6 flange

T②

X-6 flange

X-6 endX-6 flange

X-6 endRemarks••

X-6 end•Pedestal opening•

Efforts are made to improve accuracy by setting thetarget.
Many points are measured in all the sections andthe data is evaluated as 3D.
Measurement is carried out in detail as it is based on
the structural shape.
The pedestal opening is evaluated as a surface andthe central axis is obtained.

(Coordinates are obtained by overlapping)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.79① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation〇 Test method
1) Target ① and ② are installed on the simulated Reactor Building wall surface and the simulated isolation chamber wall surface of the mock-up.
2) Correlation data between ① and ② is collected by 3D scanning (Measured data A).
Some simulated
interfering objects(simulated using
scaffolding, etc.)

3D scanner temporarystorage platform

Simulated X-6 (simulated scaffolding
material)
penetration

3D scanner

Pedestal
opening

CRD rail (simulatedusing scaffolding, etc.)

Target ①

Target ②

Measured data A

3) The simulated air-tight door is removed, and the simulated back hatch is installed.
4) Target ③ is installed on the simulated back hatch on the inside of the isolation chamber.
5) Correlation data between Target ②, ③ and X-6 penetration flange is collected by 3D scanning (Measured data B).
3D scanner temporarystorage platform (simulated
scaffolding material)

Simulated back hatch

Some simulated interfering
objects (simulated using
scaffolding, etc.)

Pedestal
opening

CRD railTarget ③

Target ②

X-6 penetration
flangeMeasured data
A6) The 3D scanner is moved to the vicinity of the X-6 penetration flange.
7) Correlation data between Target ③ and the area from X-6 penetration flange to the end of the X-6 penetration on the PCV side is collected by 3D scanning(Measured data C).
3D scanner temporarystorage platform (simulated
scaffolding material)

Simulated back hatch

Some simulated interfering
objects (simulated using
scaffolding, etc.)

Pedestal
opening

CRD rail (simulated using
scaffolding, etc.)

Target ③

X-6 penetration
flangeEnd of X-6 penetration on
the PCV side

Measured data C©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.80① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation
8) The 3D scanner is moved to the central part inside the X-6 penetration.
9) A partitioning wall is installed between Target ③ and the X-6 penetration flange.
10) Correlation data between Target ③ and the area from X-6 penetration flange to the end of the X-6 penetration on the PCV side is collected by 3D
scanning (Measured data D).

Simulated back hatch
Partitioning wall

X-6 penetration
flange3D scanner temporarystorage platform (simulated
scaffolding material)

End of X-6 penetrationon the PCV side

Some simulated interfering
objects (simulated using
scaffolding, etc.)

Pedestal
opening

CRD rail (simulatedusing scaffolding,etc.)

Measured data D11) The 3D scanner is installed on the temporary storage platform for the simulated CRD rail part.
12) Correlation data between the pedestal opening and the end of the X-6 penetration on the PCV side is collected by 3D scanning (Measured data E)

3D scanner(Tracker)

Simulated back hatch

End of the X-6 penetrationon the PCV side

Inner surface of the pedestal
opening

Measured data E©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.81① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation
13) The Measured data A-E is integrated (No. 78 sheet), and coordinates (1) (Target ①), coordinates (3) and coordinates (4) (pedestal opening) are acquired.

The point cloud data obtained
from the 3D scanner isconverted to coordinates① Integration of point cloud data
Simulated Reactor Building wall

Simulated isolation chamber wall

② Acquisition of coordinatesfrom the integrated data
Simulated X-6 penetration③ Acquisition of coordinates to be used
Some simulated
interfering objects(simulated using
scaffolding, etc.)

Pedestal opening

Simulated CRD rail
Straight line (a)Target ①-1

Straight line (c)Coordinates (1)(Acquired from the 3D
measurement results)

Target ①-2
Approx. 13000mm

Pedestal opening

Coordinates (2) (interim coordinates)(Acquired from the 3D measurement
results)

Coordinates (3)(Acquired from the 3D
measurement results)

Coordinates (4)(Acquired from the
3D measurement
results)

Straight line (b) Reference line for installation based on the measurement results# The straight lines and the reference line for installation are marked by usinga laser marking instrument to check the horizontal and vertical lines.

14) The pedestal opening and the simulated part of the Reactor Building wall surface are at a distance and hence interim coordinates are established from theviewpoint of making marking easier. Therefore a laser marking instrument is used to mark straight lines (a), (b) and (c).
Coordinates (2) of the point where straight line (c) intersects are obtained.
15) A straight line passing through the coordinates ascertained from the integrated data obtained after 3D measurement is marked.
(This straight line becomes the reference line for installation.)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.82① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation〇 Classification of the collected data
3D measurement is conducted 3 times and the data obtained is said to be N-1, N-2 and N-3 respectively.
Also, the following 3 cases were implemented for the method of integrating the measured data A - E.
◆ Case 1
・The measured data (A-C) is integrated using only the targets.
・ Since there are no targets for measured data (D and E), data is integrated using the test piece structure.
◆ Case 2
・ The measured data (A-C) is integrated not only using the targets but also using the test piece structure.
・ Since there are no targets for measured data (D and E), data is integrated using the test piece structure.
◆ Case 3
・ Measured data (A-E) is integrated using all available data (Targets, test piece structure, building, etc.)〇 Accuracy verification method
The reference line for installation (a) while assembling the test piece and the reference line (b) based on the measured data wereactually measured and errors were verified.
The following 4 locations were verified.
X-6 penetration flange
Pedestal opening: Reference line (a): Reference line (b)CRD rail (simulatedusing scaffolding, etc.)

Accuracy verification ④

Accuracy verification ③ Accuracy verification ② Accuracy verification ①©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.83① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation
Measurement
items

ケース1
Case 1

Case
2
ケース2

ケース3
Case 3①-8.1 mm

7.8 mm

4.2 mm②-8.1 mm

7.8 mm

4.8 mm③-1.8 mm

4.8 mm

8.5 mm④

8.1 mm-0.9 mm

16.1 mm

角度ズレ-0.04°

0.02°-0.03°

25.0 mm21.2 mm

1.8 mm②

24.9 mm21.2 mm

2.5 mm③

17.3 mm17.5 mm

4.9 mmData 計測項目〇 Test results データ

N-1

Angle
misalignment

①
N-2

N-3

Maximumvalue④

4.1 mm12.1 mm10.1 mmAngle
misalignment

角度ズレ

0.05°

0.02°

-0.02°①-19.0 mm-8.1 mm-1.6 mm②-18.0 mm-8.0 mm-0.5 mm③-3.5 mm

0.5 mm

1.6 mm④

23.1 mm15.1 mm

8.1 mmAngle
misalignment-0.10°-0.06°-0.02°

角度ズレ
Common共通⑤

Remarks
備考

Reference:
基準：≦50mm

Reference value

参考値（計算値）(calculated value)

Reference:
基準：≦50mm

Reference value

参考値（計算値）(calculated value)

Reference:
基準：≦50mm

Reference value

参考値（計算値）(calculated value)
For calculating the
角度計算用
angle

23920 mm
X-6 penetration flange

Pedestal opening

CRD rail (simulatedusing scaffolding, etc.)

Accuracy verification ④

Accuracy verification ③

Accuracy verification ②

Accuracy verification ①©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.84① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ①-3 Establishment of the method of marking the reference line for installation〇 Test results and considerations
1) In case 1 the maximum error was 25.0mm, in case 2 the maximum error was 21.2mm and in case 3 the maximum error was
16.1mm.
The error in the pedestal opening was less than 50mm (acceptable error). Thus the errors in all the cases were within the margin oferror.
2) It was confirmed that the reference line for installation can be obtained by ascertaining the relative positional relationship from the pedestal
opening to the R/B wall surface by 3D scanning measurement.
3) The error in case 3, which has the most data to be integrated, is the least. It was found that accuracy improves furthermore if all available
data is used while integrating the measured data.

The results of the tests conducted at actual scale (1/1) showed that an error accuracy of less than 25mm can be ensured for the central
axis of the pedestal opening when the cell is installed in accordance with the reference line for installation obtained using the 3D
scanner, and that it will be possible to insert the robot arm even in its current size.
〇 Future challenges
It is determined that the following will need to be considered in the future for securing a risk margin assuming 1) the impact ofenvironmental factors inside the PCV (scanner being under high radiation environment), and 2) impact of the status inside the PCV (dust,etc.).
① Confirming the impact of the 3D scanner being under high radiation environment② Increasing the installation risk margin by modifying the structure
・ Trying to increase the risk margin by making it possible to adjust (movable) rail used for inserting the arm into the cell.
・ Reducing (appropriately) the size of arm, particularly the actuator to increase risk margin.
・ Extending the internal wall of the cell which is likely to interfere with the cell if the actuator of the arm shifts laterally,©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.85① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell adapter can be processed](Aim)• A gap of 5mm or less needs to be provided for the welded connection surface between the cell adapter and the PCV.
• Hence, not just the installation accuracy but also the accuracy of the PCV connection surface of the cell adapter needs to be good.
• Therefore, the method of acquiring data will be substantiated and verification test will be conducted assuming that the three dimensional data on the PCV
surface will be obtained and 3D processing will be carried out.
(Expected outcome)• Establishment of the method of acquiring 3D processed data using a 3D scanner and verification of the processing accuracy of cell adapter.

➢

The PCV connection surface of the cell adapter is processed based on the data obtained by 3D scanning the simulated PCV steel plate, and it is verified whether or not thefinishing is according to the design shape based on the measured data.
・ 3D scanning of the simulated PCV steel plate is performed, and the data required for designing the shape of the PCV connection surface is acquired.
・ The cell adapter processing model is created using the 3D scan data.
・ The PCV connection surface of the cell adapter is processed based on the processing model, and the finished state is verified.
⇒ Verification of the feasibility of 3D scanning of the lower part of the X-6 penetration (confined space) (Verification of whether or not PCV connection surfaces withcomplex shapes can be processed)

BSW

PCV steel plate(simulated)

BSW opening

3D scanning of the simulated PCV steel plate surface including the X-6
penetration is performed(Acquisition of multiple data)

Shielding door (simulated)

Creating a 3D model of the PCV steel plate surface by integrating multipledata
3D scanner
Shielding door frame(Simulated)[Supplement]
Lower part of the X-6
penetration (confined space)
Verification of feasibility of
3D scanning

Designing (processing model) and processing of the cell adapter PCV
connection surface shape
3D scanning and creating a 3D model of the cell adapter (finished product)X-6 penetration(Simulated)
Building floor
3D scanning was performed at a prescribed location and PCV
connection surface was manufactured based on those results.
Illustration of the scanning test of the PCV steel plate surface

Verifying the finished state by comparing with the cell adapter (finishedproduct) and the 3D model of the PCV steel plate shape[Data acquired by means of 3D scanning]【3Dスキャンでの取得データ】
・PCV
steel plate shape
・PCV鋼板形状[Supplement]
1/2 scale simulation (Considering work efficiency during the test)

・Requiredlength of the cell adapter
・セルアダプタの必要長さ
・Positionof the guide pin
・ガイドピン位置©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.86① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation
procedures

After 3D scanning the
PCV steel plate(simulated) surface, thecell adapter is processed
to match the shape of the
PCV steel plate[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell adapter
can be processed]

・Time of implementation： Early October 2022 onwards (Tests completed)・Location: In the premises of the Mitsubishi Heavy Industries, Kobe Shipyard
・Test piece: 1/2 scale (Element test ③, used for the overall verification test as well)
6100

Drawing of the inner surface of cell adapter

X-6 penetration(simulated)
PCV steel plate (simulated)

Shielding door (simulated)

BSW(simulated)

Auxiliary shielding(simulated)

BSW (simulated)

Auxiliary shielding(simulated)
Guide pin

3500

5550

PCV steel plate (simulated)
Shielding door (simulated)

X-6 penetration (simulated)

Verification of feasibility of
3D scanning of the PCV
steel plate surface in thelower part of the X-6
penetration

Cell installation frame(simulated)

Cell installation frame(simulated)

Test piece

Floor plan

Test piece

Cross-section©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.87① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surfaceof the cell adapter can be processed]

・ Verification of the finished state of the cell adapter① A 3D model of the cell adapter is created by 3D scanning the cell adapter forwhich the connection surface with the PCV steel plate has been processed.
② The finished state of the PCV connecting surface of the cell adapter is verified bycomparing the 3D model of the cell adapter after processing and the 3D model ofthe PCV steel plate surface shape.
Cell adapter 3D model after processing (Illustration)[Approach towards determining processibility]
The finished state is verified as reference, and the final determination is based on the results of verifying the gap after inserting the cell adapter
during element test ③.
Verification of the conformance with

the PCV steel plate connection
surface shape

Shielding door (simulated)

Verification of the
distance between theshielding door frame
and the PCV steel
plate

Auxiliary shielding

Cell adapter

Simulated PCV
Simulated X-6 penetration©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.88① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ② Verification of whether or not the PCV connection surface of the cell adapter can be processed]
・ The cell adapter is manufactured based on the data obtained from the 3D scan of the simulated PCV steel plate.
・ Three dimensional verification of the finished state of the PCV connecting surface of the cell adapter.
⇒ It was found that there is a gap of about 4mm in the model. (The results of actual measurement were equivalent.)
Fine adjustments are made to the connecting part from there so that the dimensions of the finished product are within the criteria.
(Criteria： 2.5mm > Result 2.4mm)
3D measurement of the simulated PCV
Marking of
the reference
points(3 locations)
Simulated PCV
steel plate(To bemeasured)

3D measurement of the PCV connecting surface of the cell adapter

Cell adapter and PCV connecting part

Cell adapter

3D scanner
3D scanner

PCV steelplate<Enlarged>

Cell adapter

Cell adapter (tobe measured)

Cell adapter
measurement data

PCV steelplate

The gap is measured using a gap gauge
Gap: 2.5mm or less#Processingdata

PCV steel plate
Measured data
Marking of thereference points(3 locations)
Cell adapter connecting part in the 3D model

Gap(About 4mm)
Finished cell adapter

Result of overlapping the edges in the 3D model

Cell adapter

PCV steel plate# Criteria: Basis of less than 2.5mm⇒ Required dimensions from the remotely operated welding
equipment Since the actual gap is 5mm, here it is set to 2.5mm
which is 1/2.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.89① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell
adapter can be processed]

Target〇 Test method

PCV steelplate1) A simulated PCV steel plate part is set up, and a 3D scanner is installed at a location that is 2500mm from theX-6 penetration on the reference line for installation (approx. 1000mm from the shielding door frame) and at aheight of 880mm.
Data from 3D scanning of the front surface of the PCV steel plate is obtained using the 3D scanner.
(Measured data A).

Simulated PCV

X-6
penetration

3D scanner (installedon the upper side)
Simulated X-6 penetration

Base plate

Side view

Simulated PCV
Simulated X-6 penetration

3D scanner
Reference line for installation(Center of the X-6 penetration)

Illustration of the 3D scanner installation location (on thereference line for installation)

Marking of thereferencepoints(3 locations）

3D scanner

Simulated PCV
steel plate(To be measured)

3D measurement of the simulated PCV©International Research Institute for Nuclear Decommissioning

No.90

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell adapter can beprocessed]〇 Test method
3) The 3D scanners are installed at 2 locations that are 700mm on either side of a location that is 2500mm from the X-6
penetration end of the reference line for installation and at a height of 270mm or less.
4) Data from 3D scanning of the PCV steel plate is obtained from the 3D scanners on both sides respectively. (Measured data B,
C)
Shielding door
housing

Shielding door
housing

Shielding door

Shielding door
PCV steel plateX-6 penetration
3D scanner (installed on 2
locations on either side)
Reference line for installation(Center of the X-6 penetration)
3D scanner(installed on the underside)

X-6 penetration
Center of the X-6
penetration

PCV steel plate
Cell installation frame
Cell installation frame

Layout drawing

Side view©International Research Institute for Nuclear Decommissioning

No.91

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell adapter can be processed]〇 Test method
5) Measured data A - C is integrated to ascertain the shape of the PCV steel plate.
6) A 3D-CAD model of the PCV steel plate is created.
7) A 3D-CAD model of the shape of the cell adapter edge that connects to the PCV is created based on the 3D-CAD data on the PCV
steel plate.
8) The processing data of the distal end of the cell adapter is processed and the cell adapter is processed using a machine processor.

Distal end of adapter

3D point cloud data
(sample)Illustration of the 3D modelof the PCV steel plate

3D-CAD data on the distal end of thecell adapter

Cell adapter distal end processing©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.92① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell adapter can be processed]〇 Test results[Feasibility of 3D scan measurement including that of the gap under the X-6 penetration]1) In order to collect data pertaining to the location on the PCV steel plate front surface at the lower end of the X-6 penetration at a height of approx.

850mm above the reference line for installation, 3D scanners were installed at 3 locations (A, B and C) including the location on the reference line for
installation and 2 locations on either side of the line (left side 550mm, right side 700mm) at a height of approx. 250mm, and measurements were
performed. It was thus verified that data pertaining to the cell adapter connection part of the PCV steel plate including the gap on the underside of the X-6
penetration can be collected without any issues.

Enlarged

3D scan

To be measured (picture)
Point cloud data

PCV steel plate 3D scanning results (point cloud data)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.93① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell adapter can be processed]〇 Test results[Processed shape of the cell adapter based on the 3D scanning data]
・ The shape of the PCV connecting surface of the cell adapter is specified based on the results of 3D measurementof the PCV steel plate.
When the adjacent point cloud data is connected by straight lines, due to measurement error in 3D scanning thesurface becomes uneven. The surface is smoothened# before processing the cell adapter.
# Fine smoothening to the extent that data which is clearly noise, does not have an impact on the removal and connection.

Smoothening process

Shape before processing (3D-CAD)

Shape after processing (3D-CAD)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.94① Installation of large heavy structuresExce(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1 Verification of whether or not the PCV connection surface of the cell adapter can be processed]〇 Test results[Processing of the cell adapter and PCV steel plate connection surface, and verification of the finished state]1) According to the initial results of measurement there was a maximum gap of 4.0mm as against the allowable gap of 2.5mm or less.
2) The distal end of the cell adapter was adjusted and processed based on the initial results, and the gap was checked about reinserting.
3) By making adjustments it was possible to reduce the gap to a maximum of 2.4mm as against the allowable gap of 2.5mm or
less.
4) Based on the above, even though after the initial installation adjustments were necessary, adequate installation became possible bymaking adjustments and processing once again based on the data pertaining to the initial installation gap.
5) Moreover, by adopting the method in which the guide pin is used for insertion, installation within the gap between the pin and the pinhole became possible, and reproducibility (re-adjustment) became easier as well.
[The test was conducted at 1/2 scale this time, but the shape, curvature, allowable gap were matched and hence the results are applicable to the actual facility as well.]Distal end of the cell adapter
PCV steel plate

Measurement
計測結果

Measurement
計測結果

results (before

results (after

Measurement
計測箇所
location

Measurement
計測結果

Measurement
計測結果

results (before

results (after

①

2.0

0.7

②

1.5

0.7

⑯

2.0

0.9

⑰

1.5

③

2.0

1.2

0.7

⑱

2.0

④

0.0

2.5

1.6

⑲

3.5

1.5

⑤

3.0

1.3

⑳

4.0

1.7

⑥

3.0

1.5

㉑

4.0

2.3

⑦

4.0

1.8

㉒

3.5

2.0

⑧

4.0

2.2

㉓

3.0

1.7

⑨

4.0

2.4

㉔

2.0

1.0

⑩

4.0

2.0

㉕

2.0

1.0

⑪

3.0

1.4

㉖

2.0

0.9

⑫

3.0

0.4

㉗

1.5

0.8

⑬

2.0

0.9

最大
Maximum

4.0

2.3

⑭

1.0

0.0

Minimum
最小

1.0

0.0

⑮

1.0

0.7

Evaluation
評価基準：≦2.5mm
criteria:

Measurement
計測箇所
location

Gap verification
marking x 27

Gap

Cell adapter distal end gap measurement location

（調整前）
（調整後）
adjustment)
adjustment)

（調整前）
（調整後）
adjustment)
adjustment)

Cell adapter distal end gap measurement results©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.95① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Result]: Element test plan ②-1

Verification of whether or not the PCV connection surface of the cell adapter can be processed]〇 Test results and considerations

Effect of the polish removal spray1) The mirror surface (polished) condition of the PCV surface is[Cross section of the measurement
result (enlarged)]

likely to have caused the 4mm error in the initial gap measurement
results.

The polished PCV steel plate surface
Approx. 2mm
Absent2) Since the work of removing the coating from the PCV steel plate

Present

before performing 3D scanning measurement was initially
The reduction in noise (unevenness) was verified

assumed to be part of the work procedure, the picture was taken in

by comparing the measurement results before andthe polished condition.
While performing the measurement at the actual facility, a laser
scanner will be used and a polish removing spray#, etc. will be

used so that the shining surface does not have an impact.

after application of the polish removal spray.

Picture of the PCV steel plate

Name: HELLING

3-D Anti Glare Spray

Color: White# Based on the measurement results obtained from the additional
test after using the polish removal spray, when the cell adapter end
was manufactured once again, the maximum gap was 1.6mm.

[Operation at the actual facility]
The procedure while using the actual facility was revised, so that a rigid template member processed based on the results ofmeasurement performed using the 3D scanner is first inserted, the gap after insertion is confirmed and the template is pulled out,
the PCV steel plate connecting surface is processed further, the shape with which the gap can remain within the allowablevalue is finalized, and then the cell adapter is processed.Thereafter the cell adapter is processed and installed. This revised
procedure further improves accuracy.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.96① Installation of large heavy structuresExce(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-1 Verification of the method of installing the cell adapter by remote operation(Aim)• As the cell adapter is a high-dose radiation environment, it is required to be transported and installed by remote operation,
and a gap of 5mm or less needs to be provided for the welded connection surface between the cell adapter and the PCV inorder to ensure welding integrity.
• Hence the transportation method and installation method of the cell adapter are substantiated, the validity of the studied
structure is confirmed by verifying the insertion procedure through tests and the required specifications if the operation
has to be performed remotely are identified.
(Expected outcome)• Establishment of cell adapter transportation and installation methods, verification of installation accuracy, validation of theboundary structure and clear specification of required specifications of the equipment for remote operation.
➢ The cell adapter (manufactured during the element test ②) is inserted in the simulated body, and the interference risk, positioning and workability areverified.
・ The cell adapter is loaded on a simple cart and is inserted into the BSW opening along the cell installation frame.
・ The risk margin of interference with the shielding door, BSW opening and the X-6 penetration when the work of inserting the cell adapter is being
performed is verified.
・ It is verified that the gap between the shielding door frame/PCV steel plate frame and the cell adapter is within the allowable range.
BSW opening

PCV steel plate(simulated)
Shielding frame(simulated)#A simple cart is used, andthe cell adapter istransported along the rail
for cell transportation

The simple cart on which the cell adapter is loaded is installed on the cell installation frame

The height of the cell adapter is adjusted (Height ①)

The cell adapter is moved forward towards the PCV until it completely enters the shielding door frame

The height of the cell adapter is adjusted (Height ②)

Shielding door
(simulated)
X-6 penetration(simulated)
Building floor[Supplement]
The risk margin of interfering
during insertion and theworkability are verified, and therequired specifications forremote operation are identified.

The cell adapter is inserted completely into the PCV (positioned using a guide pin)Accuracy of the installation position (Top and bottom, left and right: error ± 7.5mm or less)

Cell adapter

Cell installation frame
Verification of the gap with the PCV steel plate/shielding door frame (2.5mm or less)Illustration of the work of transporting the cell adapter#The simulated body used in element test ② is used.

[Supplement]
The method of remotely verifying
the gap is considered.

©International Research Institute for Nuclear Decommissioning

No.97

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of
the installation procedures[Results]: Element test plan ③-2 Verification of the method of installing thecell adapter by remote operation

Cell adapter insertion workflow
The simple cart on which the cell adapter will be loaded isinstalled on the cell installation frame.
The cell adapter is loaded on the simple cart.

Important points related to positioning the cell adapter
・ Horizontal adjustment of the cell adapter (making sure the cell adapter flange surface is perpendicular)・ Centering of the cell adapter with respect to the reference line for installation
Cell adapter
Being perpendicular

Cell adapter flange surface

The position of the cell adapter on the simple cart isadjusted.
(Centering, leveling)
Change in shape (vertical) of the cell adapter in its
installed state is checked.

Guide pin

Guide hole

Simple cart

Reference line for installation

The simple cart is moved forward along the cell
installation frame up to the shielding door.

Cell adapter

X-6 penetration

Height of the cell adapter is adjusted (Height ①)
The cell adapter is moved forward towards the PCV until it
is completely inside the shielding door frame.

Height of the cell adapter is adjusted (Height ②)
The cell adapter is inserted completely on the PCV side.
(Positioning with the help of the guide pin)・ Change in shape of the cell adapter when it is loaded on to the simple cart (vertical direction)
Since the cell adapter is held in place by the sipping bolts, the bellows part does not sag,but this is verified for reference.
・ It is ensured that the cell adapter can be moved forward without any shift in its position and after
moving forward the position of the cell adapter is checked once again.
・ The guide pin is centered with respect to the guide hole (fine vertical adjustments)

Verification of the gap with the PCV and verification of thecell adapter installation position

The feasibility of positioning the cell adapter with the guide pin method is verified in thiselement test.

[Actions to be taken if the position needs to be corrected] If the gap exceeds thepermissible value
The guide hole should be provided with a clearance of ±2.5mm*, and theposition of the cell adapter should be finely adjusted so that the gap is 2.5mm orless (the cart should be provided with an adjustment function).
* Set conservatively as against a ±7.5mm (provisional value) lateral slip
margin©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.98① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-3 Verification of the method of installingthe cell adapter by remote operation
Process
工程

Set at a height so that it
does not interfere with theshielding door housing

確認項目items
Verification

Remarks(Dimensions are based on ½ scale)
備考（寸法値は、1/2スケール基準）

Step 1
ステップ１

Cell adapter height ①
セルアダプタ高さ①

Step 2
ステップ２

Risk margin of each interference checking location
各干渉確認部のリスク裕度

Step 3ステップ３

セルアダプタ高さ②
Cell adapter height ②

Designvalue: 2000mm
設計値：2000mm

ステップ４
Step 4

Deviationof installation position
設置位置のズレ

Details on the following page
詳細は次頁

Designvalue: 360 - 460mm
設計値：360～460mm－

Gap
between cell adapter/shielding door frame
セルアダプタ/遮へい扉フレームの隙間

詳細は次頁
Details on the following pageGap
between the cell adapter/PCV steel plate surface
セルアダプタ/PCV鋼板表面の隙間

Details
on the following page
詳細は次頁

Set at a height so that it does
not interfere with the BSW
opening： Interference
checking location

The height of the guide pin
and the guide hole ismatched.

Guide hole

Positioning with the help of the guide pin

Guide pin

Guide pin

Cell adapter

Cell adapter

Cell adapter

Cell adapter

Set at a height so that the basecan be bypassed

X-6
penetration

X-6 penetration

Height ②
X-6 penetration

X-6 penetration

Height ①

Step 1
Adjusting to height ①

Step 2Inserting the cell adapter

Step 3Adjusting to height ②

Step 4Completely inserting the cell adapter(Positioning with the help of the guide pin)

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.99① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-4 Verification of the method of installing the cell adapter by remote
operation
・ Verification after inserting the cell adapter① It is verified whether the accuracy of installation position is within the permissible value (1/2 scale: ≦±7.5mm).
[Verification method]・ Shielding door frame side: The guide pin is inserted in the guide hole.
・ PCV steel plate side: Checking for shift in the position of the cell adapter from the marking of position where the cell adapter is planned to beconnected on the PCV steel plate side.
Shielding door frame
The guide pin is inserted in the guide hole.

Cell adapter

Checking for horizontal deviation

PCV steel plate
Guide pin

X-6 penetration

Checking for vertical deviation: Marking on the PCV steel plate surface

Cell adapter

X-6 penetration② The gap between the cell adapter and the shielding door frame and the gap between the cell adapter
and the PCV steel plate surface is checked to make sure it is within the permissible value (1/2 scale: ≦2.5mm).

: Gap checking
location©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.100① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of theinstallation procedures[Results]: Element test plan ③-5 Verification of the method of installing thecell adapter by remote operation
・Time of implementation： Early December 2022 onwards (Tests completed)・Location: In the premises of the Mitsubishi Heavy Industries, Kobe Shipyard
・Test piece: 1/2 scale (Element test ②, used for the overall verification test as well)
6100

Cell adapter

X-6 penetration (simulated)
PCV steel plate (simulated)

Shielding door (simulated)

BSW (simulated)
Auxiliary shieldingBSW (simulated)(Simulated)
Auxiliary shielding(Simulated)

Guide pin

3500

5550

PCV steel plate (simulated)
Shielding door (simulated)

X-6 penetration (simulated)
Cell adapter
Cell installation frame(Simulated)
Cell installation frame(Simulated)

Test piece

Layout drawing

Test piece

Cross-section©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.101① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote operation
Simulated shielding door

Cell adapter

Simulated PCV steel plate
View of the insertion test

Cell adapter transportation
cart gripper

Cell adapter
CameraCell adaptertransportation cart
Cell adapter

After installation of cell adapter

Cell adapter
Gap

Cell adaptertransportation cart

Verification of gap with the shielding
door while inserting

Image captured by the camera installed on
the cell adapter©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.102① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote
operation〇 Test method
1) A 3D model of the cell adapter is created by 3D scanning the cell adapter for which the connection surface with
the PCV steel plate has been processed.

3D scanner
Distal end of
adapter

Cell adapter

Finished cell adapter
Illustration of the 3D model of the cell adapter
after processing
3D measurement of the PCV connecting surface of the cell adapter©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.103① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote
operation〇 Test method
2) 3D measurement data is acquired while the PCV steel plate, X-6 penetration, BSW and shielding door areassembled.
Shielding door
housing

Shielding door
housing

Shielding door

Shielding door
housing

Shielding door

Shielding door
housing

Shielding door
Shielding door
X-6 penetration
3D scanner
Reference line for installation(Center of the X-6 penetration)

PCV steel plate
Guide pin

PCV steel plateX-6 penetration

3D scanner (installed on 2
locations on both side)
Reference line for installation(Center of the X-6 penetration)

3D scanner (installedon the underside)

X-6 penetration
PCV steel plate

Center of the X-6
penetration

X-6 penetration

PCV steel plate

Cell installation frame

Cell installation frame

Cell installation frame

Cell installation frame

Side view

PCV steel plate

Layout drawing

Shielding door

3D scanner

3D scanner

X-6 penetration

BSW

3D scanner at the center of the test piece3D scanner on the right side of the test piece3D scanner on the left side of the test piece©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.104① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote
operation〇 Test method

3) The measured data mentioned earlier is combined and the following items are verified.
(a.) Specification of the guide pin hole position on the cell adapter flange(b.) Ascertaining the planned gap when the cell adapter is inserted

Shielding door
housing
PCV steel
plate

＋
BSW
openingX-6
penetration

Mock-up side 3D model

The dimensions of the location
where the guide hole is to bemade are established.

Assembledusing CAD

Illustration of the 3D model of the cell
adapter after processing

Assembled using 3D CAD(Ascertaining the location on the part
where the guide hole is to be made)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.105① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote
operation〇 Test method
4) The cell adapter guide pin holes are made based on the positional dimensions confirmed using 3DCAD.

Guide pin hole on the right side

Guide pin hole on the right side

Part where guide holes are madeLocation on the part where the guide hole
is to be made indicated using 3D CAD
Making the cell adapter guide pin hole
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.106① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote
operation
Pitch adjustment(for horizontal
adjustment)〇 Test method
5) The cell adapter is loaded on the simple cart.
6) The cell adapter is positioned before starting to insert it.
•
Leveling of the cell adapter•
Making sure that the central axis of the cell adapter coincides with thereference line for installation•
Verifying the extent of change in shape (vertical sagging) of the cell
adapter7) The shielding door is completely opened.

Roller adjustment(for horizontal
adjustment)

Yaw adjustment(for central axis adjustment)

Positional adjustment
mechanism(approx. 180kg)

Lateral movement(for central axis adjustment)

Cell adapter position adjustment mechanism

Shielding door PCV steel plate

Cell adaptertransportation cart

Cell adapter transportation cart installation
status （3D CAD）

Cell installation
frameState of the cell adapter when loaded(photo)Cell adapter transportation cart installation
status (photo)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.107① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verificationof the installation procedures[Results]: Element test plan ③-5 Verification of the methodof installing the cell adapter by remote operation

Process

Verification items
Cell adapter height ①

Step 1
Step 2
Step 3
Step 4

Risk margin of the interference checking locations

Cell adapter height ②
Deviation of installation position
Gap between cell adapter / shielding door frame〇 Test method

Gap between cell adapter / PCV steel plate surface

8） The cell adapter is inserted.
a) The height of the cell adapter is adjusted so that it can pass through the shielding door frame of the shielding door and the BSW opening(Each height is verified).
b) The cell adapter flange part is moved forward until it enters on the PCV side from the end of the shielding door frame while checking forinterfering objects (The margin for interference and the heights of the positions are verified).

Shielding door

Shielding door

Height at which there isno interference with theshielding door housing

Simulated X-6 penetration
ShieldingdoorInterference
checking location

Simulated
PCV
Height at
which there is

Simulated PCV
Cell adapter

Insertion no interferencewith the BSW
opening part

Cell adapter

Simulated X-6 penetration

Simulated PCV

Cell adapter

Cell installation frame
Height at which the base can be bypassed

Cross-section of Step 1

Status at Step 1 (photo)

Step 2 from the top

Cross-section of Step 2©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.108① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of
the installation procedures[Results]: Element test plan ③-5 Verification of the method of
installing the cell adapter by remote operation〇 Test method

Process

Verification items
Cell adapter height ①

Step 1
Step 2
Step 3

Risk margin of the interference checking locations

Step 4

Deviation of installation position

Cell adapter height ②
Gap between cell adapter / shielding door frame
Gap between cell adapter / PCV steel plate surface

8) The cell adapter is inserted.
c.) The height of the cell adapter is reduced so that the height of the guide pin on the shielding door frame side and that of the guidehole of the cell adapter coincide (The margin for interference and the heights of the positions are verified).
d.) The cell adapter is moved forward until the tip of the cell adapter comes in contact with the PCV steel plate surface while checking
the margin for interference and making sure that the guide pin on the shielding door frame side enters the cell adapter guide hole.
Fine adjustments are made as required in the position of the cell adapter (The margin for interference and the heights of thepositions are verified).
Shielding door

Shielding door

Shielding door
Shielding door

Simulated X-6 penetration

Simulated X-6 penetration
Guide pin
Guide hole

Height at which there isno interference with the
BSW opening
Cell adapter

Simulated PCV
Simulated PCV

Simulated X-6 penetration

Simulated X-6 penetration
Cell adapter

Cell adapter
Cell adapter

Simulated PCV

Simulated PCV

Cell installation frame

Cell installation frame
Height at which there is no interference with
the BSW opening / X-6 penetration /shielding door frame

Step 3 from the top

Cross-section of Step 3

Step 4 from the top

Cross-section of Step 4©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.109① Installation of large heavy structures

Process
Step 1
Step 2
Step 3
Step 4(6) Implementation items (6) -3 -1： c. Element test verification of theinstallation procedures[Results]: Element test plan ③-5 Verification of the method of installing thecell adapter by remote operation

Verification items
Cell adapter height ①
Risk margin of the interference checking locations

Cell adapter height ②
Deviation of installation position
Gap between cell adapter / shielding door frame
Gap between cell adapter / PCV steel plate surface〇 Test method[Verification of the margin of interference with the shielding door and the BSW opening
when the cell adapter is inserted]a.) Verification of margin of interference in Step 1
・Only the position is set, as the cell adapter is in its initialstate before transportation.
Shielding door

Height at which there is no interferencewith the shielding door housing①
Status at Step 1 (Picture)②
Insertion

Height at which there
is no interferencewith the BSW
opening③
Cell adapter

Height at which the base can be bypassed

Cross-section of Step 1

Verification
確認部位site

Simulated PCV№
セルアダプタ側Cell
adapter sideTop of the tip① 先端上面

Simulated X-6 penetration

Item with which there
is干渉対象物
interference

Actual
実測値
measured
value
(mm)
(mm)

Design
設計値
value

(mm)
(mm)

BSW開口上面Top of BSW opening

100

95

遮へい扉ハウジング
Shielding door housing

91

71

Bottom of the tip 遮へい扉ハウジング
Shielding door housing③ 先端下面5171②

Upper end of the
フランジ部上端
flange part[Considerations and evaluation]
・ Since the difference between ② and ③ is the cell adapter flange, a broader area is set
from the perspective of making the gap between the upper end and the BSW visible(the lower end is visible).
・ As the cell adapter is in its initial state before insertion, similar settings are planned
to be made when working with the actual cell adapter or improvements are planned tobe made using a camera.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.110① Installation of large heavy structures

Process
Step 1
Step 2
Step 3(6) Implementation items (6) -3 -1： c. Element test verification of the installation
procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter
by remote operation

Step 4

Verification items
Cell adapter height ①
Risk margin of the interference checking locations

Cell adapter height ②
Deviation of installation position
Gap between cell adapter / shielding door frame〇 Test method

Gap between cell adapter / PCV steel plate surface[Verification of the margin of interference with the shielding door and the BSW opening when the cell adapter is inserted]b.) Verification of margin of interference in Step 2・ It is determined that as the BSW opening is small it would be advisable to increase the margin on bothsides of the tip.
Shielding door

Gap

BSW

Gap
⑥

Gap

Cell adapter

④
②

№

①
Cell adapter⑤

Simulated PCV

Simulated X-6
penetration

Cell adapter

③

⑦
Gap

Gap

Gap

Step 2 from the top

Cross-section of Step 2

確認部位site
Verification
セルアダプタ側Cell
adapter side

Item with which there is
干渉対象物
interference

Actual
実測値
measured
value
(mm)
(mm)

Design
設計値
value

(mm)
(mm)

①

Top of the tip
先端上面

Top of the BSW
BSW開口上面
opening

100

95

②

Upper end of the
フランジ部上端
flange part

Shielding door housing
遮へい扉ハウジング

91

77

③

Right surface of the BSW開口右面
Right surface of the BSW
先端右面
tip
opening

8

16

④

先端左面
tip

Left surface of theLeft surface of the BSW
BSW開口左面
opening

23

16⑤

Right tip of the
フランジ部右端
flange part

Shielding door housing
遮へい扉ハウジング

62

77

⑥

Left tip of the flange 遮へい扉ハウジング
Shielding door housing
フランジ部左端
part

59

77

⑦

Bottom of the tip 遮へい扉ハウジング
先端下面
Shielding door housing

51

71[Considerations and evaluation]
・ It is believed that the difference in ③ and ④ is caused by the shift at thetime of insertion.
・ While working at the actual facility improvements are planned to be madeby constantly monitoring with a camera.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.111① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by
remote operation〇 Test method[Verification of the margin of interference with the shielding door and the BSW opening when the cell adapter isinserted]c.) Verification of margin of interference in Step 3
・ As the tip of the cell adapter flange part is not visible during insertion, verification is performed
using a camera, etc.
Process
Step 1
Step 2
Step 3Gap
Gap

Step 4Gap
Shielding door

Verification items
Cell adapter height ①
Risk margin of the interference checking locations

Cell adapter height ②
Deviation of installation position
Gap between cell adapter / shielding door frame
Gap between cell adapter / PCV steel plate surface③
Simulated X-6 penetration⑤

Height at which there isno interference with the
BSW opening①

Cell adapter

Simulated PCV
Simulated X-6 penetration

Cell adapter

④

⑥

②
Gap

Verification
確認部位site

Guide pin
Guide hole

Height at which there is no interference with the BSW
opening / X-6 penetration / shielding door frame

Step 3 from the top
Cross-section of Step 3№Celladapter side
セルアダプタ側

Item with which there
干渉対象物
isinterference

Actual
実測値
measured
value
(mm)
(mm)

Design
設計値
value

(mm)
(mm)

①

Top of the tip
先端上面

Top of the BSW opening
BSW開口上面

51

47

②

先端右面
tip

Right side of theRight side of the
BSW開口右面
BSW opening

25

30

③

Left side of the
先端左面
tip

Left side of the BSW
BSW開口左面
opening

35

30④

Right end of the
フランジ部右端
flange part

遮へい扉ハウジング
Shielding door housing

62

67

⑤

Left end of the
フランジ部左端
flange part

遮へい扉ハウジング
Shielding door housing

77

67

⑥

先端下面
Bottom of the tip

Lower end of the X-6
X-6ペネ下端
penetration

72

64

⑦

先端下面
Bottom of the tip

Bottom of the BSW
BSW開口下面
opening

34

39[Considerations and evaluation]
・ The numbers when installation is half way through can be used for the differencewith the design value without any problems.
・ Visibility is good. While working at the actual facility insertion is planned to be
performed by constantly monitoring with a camera.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.112
Process
Verification items① Installation of large heavy structures
Step 1
Cell adapter height ①(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter
by remote operation

Step 2
Step 3
Step 4

Risk margin of the interference checking locations

Cell adapter height ②
Deviation of installation position
Gap between cell adapter / shielding door frame
Gap between cell adapter / PCV steel plate surface〇 Test results[Verification of the margin of interference with the shielding door and the BSW opening when the cell adapter is inserted]

Gap verification
marking x 27

[Considerations and evaluation]1) After insertion, when the gap with the opening part was verified, it was found that an almost sufficientgap was secured, and thus the cell adapter can be favorably installed.
2) It was possible to keep a gap of maximum 2.4mm with the cell adapter after insertion as against theallowable gap of 2.5mm or less.

3) While positioning the cell adapter its entire length needs to be adjusted. The adjustment can be
performed using the sipping bolts in between the bellows (The effectiveness of adjustments made using
the sipping bolts is verified.)【隙間計測結果】[Gap
measurement results]
Shielding door
Simulated X-6
penetration

Shielding door

Sipping bolts

Simulated PCV
Simulated X-6
penetration

Cell adapter

Cell adapter
Simulated PCV

Cell installation frame

Step 4 from the top

評価基準：≦2.5mm
Evaluation
criteria: ≦2.5mm

Gap
Gap
Gap
MeasurMeasurMeasur 隙間計測結果
計測 隙間計測結果
計測
計測 隙間計測結果
ement
measurement ement measurement ement measurement
location
location
location
箇所(mm)
箇所 result
(mm)
箇所
(mm)
(mm)
result(mm)
result(mm)

Cross-section of Step 4

Status after installation

①

0.7

⑪

1.4

㉑

2.3

②

0.7

⑫

0.4

㉒

2.0

③

0.7

⑬

0.9

㉓

1.7

④

1.6

⑭

0.0

㉔

1.0

⑤

1.3

⑮

0.7

㉕

1.0

⑥

1.5

⑯

0.9

㉖

0.9

⑦

1.8

⑰

1.2

㉗

0.8

⑧

2.2

⑱

0.0

⑨

2.4

⑲

1.5

⑩

2.0

⑳

1.7

Results of verifying the gap between the cell adapter and PCV steel
plate after installation©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.113① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote operation〇 Test results[Verification of the margin of interference with the shielding door and the BSW opening when the cell adapter is inserted]
1) The gap with the opening part was verified when the cell adapter was inserted and it was found that an almost
sufficient gap was secured, and thus it became possible to install the cell adapter favorably.
2) However, there was a deviation of 8mm and 23mm in the gap between the distal end of the cell adapter and theshielding door frame.
(This is assumed to have been caused by the deviation at the time of insertion).
3) It is determined that there are no issues while working at the actual facility as continuous monitoring is
performed using a camera, etc., but in an effort to increase the risk margin (including visibility, etc, while
verifying the gaps), increasing the gap to about 50mm (1/1 scale) with respect to the dimensions (horizontal) of
the opening in the lateral direction of the shielding door housing and the cell adapter flange connecting platepart is considered as well.
Further, the test was conducted at 1/2 scale this time, but the shape, curvature, allowable gap were matchedand hence the results from the following page onwards can be applied to the actual facility of 1/1 scale.
Moreover, during the test the rigidity of the bellows is maintained by the sipping bolts and thus it does not pose
any issues in measuring the interference and gap during insertion.
Further, it was confirmed that the length can be adjusted with the help of sipping bolts.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.114① Installation of large heavy structures(6) Implementation items (6) -3 -1： c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote
operation〇 Test results[Validity of the guide pin and the guide hole position/size]
1) The cell adapter was inserted while positioning with the help of the guide pin, with pin size φ12mm and hole size φ22mm.
(Since the gap between the BSW and the cell adapter was approx. 25mm, the size of pin hole was kept at approx 22mm.)
Also, the location of the guide hole made on the cell adapter was finalized by verifying the connecting surface between the PCV steel
plate and the cell adapter using 3D scanning data.
2) When the cell adapter was completely inserted, it was confirmed that the guide pin was inserted into the guide hole without any
issues, and that there was a gap of 1mm or more between the guide pin and the guide hole.
(While working at the actual facility as well, the guide pin will be observed with the camera on the cell adaptertransportation cart, and based on that the position can be adjusted.)Also, the insertion position can be replicated within the scope of the guide pin.
3) It was confirmed that the installation method using the guide pin can be implemented without any issues.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.115① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote operation〇 Test results[The points to be remotely monitored while inserting the cell adapter]
1) The interference with the shielding door housing or the BSW opening, and the positioning of the guide pin were verified with the help of aremotely operated camera.
2) In this test as well, the points to be remotely monitored while inserting were verified by installing a monitoring camera.
3) Moreover, the points that were monitored visually were identified as points to be remotely monitored.
Based on the above, it was determined that the cell adapter can be inserted while visually checking the status of the gaps remotely by
installing cameras at the following points.
In the future, the method of fixing the cell adapter and the method of cable routing will be studied in detail.
・ Monitoring camera ①, ②
: For checking for interferences on the upper side of thecell adapter
・ Monitoring camera ③, ④
Shielding door

: For checking for interferences on the side of the cell

Shielding door

Monitoring
cameraSimulated X-6
penetration

adapter・ Monitoring camera ⑤: For checking for interferences on the lower side of the

Simulated PCV

cell adapter
・ Monitoring camera ⑥

Cell adapter
Cell adapter

Simulated X-6
penetration: For checking for interferences on the top of the cell
adapter・ Monitoring camera ⑦, ⑧

Simulated PCV: For checking the guide pin / guide hole

Cell installation frame©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.116① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote operation
Consolidation of requirements concerning the cell adapter transportation cart
The required specifications and required functions of the equipment for remote transportation of cell adapter were noted.
Further, the work to be performed remotely on said part was planned to be divided among the equipment required for remote operation in thesurrounding.
№

Required equipment

Requirements

Required functions

1

BSW drilling equipment

Making an opening in the BSW

Drilling the required opening (□3100mm)
Detecting the PCV steel plate2

X-6 penetration cutting equipment

Cutting the X-6 penetration plug and X-6 penetration

Verifying (camera), cutting and removing the X-6 penetration plug
Verifying (camera), cutting and removing the X-6 penetration

3

Equipment for finishing the PCV steel
plate

Removing the coating of the PCV steel plate,removing existing weld beads

Verifying the PCV steel plate (camera)
Surface treatment by means of buffing

Grabbing, inserting, positioning, tack welding and
gap measurement of the cell adapter

Grabbing mechanism of the cell adapter
・Mechanism for carrying-in (2 shafts: forward movement, up anddown movement)
・Positioning mechanism (4 shafts: horizontal, yaw, pitch, roll)・Movement pitch (Axis of rotation: 0.5°, lift travel: 5mm/rotation)
Monitoring the gap between the cell adapter and the shielding door
(camera, clearance gauge)
Cell adapter gap measurement
Monitoring the gap between the cell adapter and PCV steel plate(camera)Temporary fixing and welding of cell adapter and PCV steel plate
Temporary fixing and welding of cell adapter and shielding door

4

Cell adapter transportation cart

5

Equipment for welding the cell adapter
and PCV

Welding, inspection of external appearance

Welding and inspection of external appearance after welding (camera)

6

Equipment for welding the cell adapter
and shielding door

Welding, inspection of external appearance

Welding and inspection of external appearance after welding (camera)

7

Equipment for removing the sipping bolts

Removing the sipping bolts (cutting)Cutting and removing the sipping bolts
Verifying the position of the sipping bolts, verifying after cutting(camera)

The test was conducted at 1/2 scale this time, the shape, gap, etc. were matched to present the requirements concerning the equipment for remote operation. Although the weight andrigidity were different than the actual facility, the rigidity of the bellows was maintained by means of sipping bolts and did not pose any issues. Thus the requirements can be applied asthey are. However, handling the weight of the actual facility needs to be considered.
©International Research Institute for Nuclear DecommissioningNo.117

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote operation
Design concept of the transportation cart for the actual facility
1) The work of transporting and positioning the cell adapter and the work of tack welding shall be carried out using the same cart.
2) The cart shall be equipped with the following functions based on cell adapter transportation and position adjustment mechanism.
(a.) Groove gap visual verification function (quantification of gap dimensions by image processing)(b.) Cell adapter tack welding function(Equipped with welding torch operation mechanism, wire feeding mechanism)Approx. 4m
Vertical axis
Shielding door

Cell adaptertransportation cart
Transportation
mechanism

Tack welding mechanism
Position adjustment
mechanism

Traveling axis

Illustration of the overall cell adapter transportation cart

Shielding door
Tack welding torch
Rail for transportation

Tack welding torch

Cell adapter

Illustration of cell adapter transportation work

Cell adapter
View A©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.118① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]: Element test plan ③-5 Verification of the method of installing the cell adapter by remote operation
Clamp axis

Equipment specifications

Rolling axis (vertical)

Vertical axis

Camera for gap verification
Rolling axis
(horizontal)

Welding torch operation
axis (horizontal)

Tack welding
mechanism

Horizontal axis
Position adjustment mechanism
Axis of rotation
Traveling axis

Transportation
mechanism

Tack welding torch

Welding torch operation
axis (vertical)

Illustration of the position adjustment mechanism
and the temporary welding mechanism
Items

FunctionTransportation
mechanism

Position adjustment
mechanism

Tack welding
mechanism

Wire feeding axis

Camera for verifying the gap at the bottom end

Illustration of the overall cell adapter transportation cart

Main material

Welding torch operation axis
(Forward and backward)

Illustration of the area around the temporary welding torch diagram

Specifications
SS400, SUS304, Aluminum alloy
Cell adapter transportation, positioning, groove gap verification, tack welding function (Tig welding) *Simultaneous
welding at 2 locations possible

Axial configuration

Traveling axis, vertical axis

Actuator

Hydraulic cylinder, electric motor

Axial configuration

Clamp axis, horizontal axis, axis of rotation, rolling axis (vertical, horizontal)

Actuator

Electric motor

Axial configuration

Welding torch operation axis (forward and backward, vertical, horizontal), wire feeding axis

Actuator

Electric motor©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.119① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]: Element test plan ④ (Overall verification test)-1 Verification of viability of the boundary components(Aim)• The method of installing the overall components (shielding door, cell adapter, cell installation frame) including the cell will be
substantiated and the boundary components will be verified.
(Expected outcome)• Establishment of the method of carrying-in and installing the overall components and verification of viability of the boundary
components.
➢

The simulated fuel debris retrieval cell (partially simulated) is installed in the test equipment used in element tests ②, ③ and theboundary components are verified.
・ The simulated cell is mounted on the cell installation frame and is moved along the cell installation frame up to the shieding
door side.
・ The simulated cell and the shielding door connecting plate are fastened.
・ The boundary part is verified.
⇒ It is verified that the boundary has been formed.

BSW (simulated)

Preparing for simulated cell installation (Verifying that the shielding door is “closed”)
PCV steel plate (simulated)

Shielding door
housing (simulated)

Connecting plate

Simulated cell

Cell adapter

Mounting the simulated cell on the cell installation frame

Moving the simulate cell up to the shielding door frame along the cell installation frame

Fastening the flange for connecting simulated cell to the shielding door frame

Shielding door
(simulated)

Cell installation frame

Illustration of simulated cell installation#Simulated body is shared between element tests (2) and (3)Verifying the housing part from inside (The shielding door should be “Open”)[Supplement]# The simulated body is at ½ scale.
©International Research Institute for Nuclear DecommissioningNo.120

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]: Element test plan ④ (Overall verification test)-2 Verification of viability of the boundary components
・Time of implementation: Mid December 2022 onwards (Tests completed)・Location: In the premises of the Mitsubishi Heavy Industries, Kobe Shipyard

・Test piece: 1/2 scale (Used in element tests ② and ③ ＋ simulated cell casing)
6100

Shielding door
housing

Handrail (for verification work)
Connecting plate

Auxiliary shielding

Simulated X-6 penetration
PCV simulation

BSW
Cell adapter

AuxiliaryshieldingBoundary part
(Red line)

3500

5550

Simulated cell
Shieldingdoor

Simulated cell

Cell installation frame

Cell installation frame

Test piece

Layout drawing

PCV simulation

Test piece

Simulated X-6 penetration

Lateral view

©International Research Institute for Nuclear DecommissioningNo.121

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]: Element test plan ④ (Overall verification test)-2 Verification of viability of the boundary components
・ The simulated fuel debris retrieval cell is installed and whether the boundary from the cell to the PCV steel plate has been formed is verified.
[Further, the test was conducted at 1/2 scale this time, but the shape, gap and curvature of the boundary part were matched and hence the results are applicable to theactual facility of 1/1 scale.
(Since the test is conducted at 1/2 scale, the rigidity of the flange part, etc. is higher, but to an extent that can be sufficiently taken into consideration while designing.)]
Simulated shielding door
Simulated BSW

Simulated BSW opening part
PCV steel plate

3500mmSimulated fueldebrisretrieval cell

Cell adapter

Simulated frame forcarrying-in the cell

[Verification of the boundary at the connecting part (part with the red dotted line)][Boundary structure]
Shielding door①

PCV steel plate②

X-6 penetration

Shielding door

Cell adapter③

BSW

Fuel debris retrieval cell
Cell adapter②

Boundary

PCV steel plate①③

Cell adapter

Shielding door

Fuel debris retrieval cell

Cell adapter©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.122① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures[Results]： Elemental test plan Main verification items[Key results]
Test

Element test ①

Element test ②

Verification items

Verification method

Method of marking
the reference line
for installation

Verifying the actual value of thereference line for installation
obtained by means of the 3D
scanner by simulating the length
based on the actual facility

Whether of not thecell adapter can beprocessed

Comparison of the shape of thecell adapter and the shape of the
PCV steel plate after processing

Evaluation criteria

Allowable error≦±50㎜

Gap between the PCV
steel plate and the cell
adapter: ≦2.5mm

Interference between the cell
adapter and shielding door frame

Element test ③(Verification ofease ofinsertion)

Risk margin ofinterference during
insertion

Element test ③(Identificationof required
specifications)Overallverification test

Verification of theoperation of
inserting the cell
adapter and themethod ofpositioning it

Verification ofboundary formation

Maximum error 25mm

There is no interference
during insertion

Effectiveness of the guide pin
insertion method

Positioning should bepossible within the rangeof the guide pin and it
should be possible toreproduce thephenomenon

・ It is possible to position and insert
without any issues
・ Can be reinserted within the rangeof the guide pin gap

Verifying the direction related toposition adjustment

Verification of number ofworking shafts

・ Mechanism for carrying-in: 2 shafts(forward movement and verticalmovement)
・ Positioning mechanism: 4 shafts(horizontal, yaw, pitch, roll)

Verifying the pitch for position
adjustment

Verifying the movement
pitch

Axis of rotation: 0.5°
Movement stroke: 5mm

Verification of speed of insertion

Speed verification

Approx. 10mm/second

Identification of items to beverified pertaining to position
adjustment

Identification of monitoring
positionCan be inserted at the monitoring point

Visual confirmation

Visual confirmation of theboundary

Confirmed that there is no gap in theboundary part

Interference between the cell
adapter and BSW

Scale ofsimulatedbody

Future examination

Technical viability /feasibility

Impact of radiation
resistance of 3D scanner

Expected to materialize
based on the prospects ofstudying the shielding
structure

Ensuring further margin forerror(Study of margin of the cellarm)

Expected to be accomplishedbased on the detailed designin the future

Reflecting adjustment anduse of luster removal spray
into the procedures for theactual facility

Expected to be implemented
by revising the operation
procedures of the actual
facility

Study of template forverifying the gap

Expected to be accomplishedthrough detailed designing in
the future

Study of BSW opening part
dimensions consideringinterference margin

Expected to be accomplishedthrough detailed designing in
the future―

The guide pin method has
been used at our company
and hence is expected tomaterialize.

Concept of the equipment
for remote operation andthe conceptual study

Expected to be accomplishedthrough detailed designing in
the future

1/1

Initial measurement: 4mm(Impact of the metallic luster of the
PCV steel plate）
After adjustment: 2.4mm(The error improves to 2mm upon
using the luster removal spray)

Gap that is almost according to thedesign is ensured and thus insertion ispossible.
(Should be inserted by shifting theposition from the perspective of
visibility in some parts)

Visual confirmation of passing
through X-6 penetration
Verifying viability ofpositioning with thehelp of the guidepinResults

1/2

Expected to be accomplishedthrough detailed designing in
future Decommissioning©International Research Institute forthe
NuclearComplete full scale mock-up
tests6. Implementation items of this project [1)(1)Development of the Method for Installing Access Equipment]

No.123① Installation of large heavy structures(6) Implementation items(6)-3-1: c. Verification of element test for the installation procedures✓

Contribution of the results towards the reflection destination
・ Contributes to substantiation of the procedures for installing access equipment inside the R/B for the side access method.
✓ Analysis from the viewpoint of on-site applicability
・ The shape, etc. of the BSW opening / PCV steel plate is simulated to the extent possible as required in the test piece and thestructure inside the Reactor Building in Unit 3, and on-site applicability is considered.
1) Ascertaining the reference location using a laser scanner and the method of marking the layout
As the pedestal opening, the X-6 penetration and the distance between buildings need to be simulated to actual scale,
1/1 scale simulation is performed. (Reference: No. 73 - 84)2) Confirmation test on alignment of the cell adapter and PCV steel plate, method of confirming the position at the time ofcarrying-in and installation, and verification of installation procedures of the cells, etc.
PCV and BSW around the X-6 penetration inside R/B are partially simulated, and the cell adapter, shielding door and fueldebris retrieval cell are simulated (Approximately 2m of the length of the fuel debris retrieval cell on the PCV connection
side is simulated).
The size of the test piece is 1/2 scale based on the margin of error in the measurement accuracy and the workability.
(Reference: No. 85 to 122)
・ Each method required for installation is a combination of general technology and considers on-site applicability to the extent
possible.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1)(1)Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-3-1: c. Element test verification of the installation procedures✓ Level of achievement compared to the goals

No.124[Objective]: To verify the viability of the following issues identified in (6)-2 by element tests.
1) Ascertaining the reference location using a laser scanner and the method of marking the layout2) Method of positioning the cell adapter with the PCV steel plate3) Method of remotely confirming the position at the time of carrying-in and installing the cell adapter
The scope of the test is to perform simple carrying-in and installation and to clearly specify the specifications required of
the remotely controlled equipment.
[Achievement status]
1) Establishment of the method of marking the reference line for installation
・ Study on the method of ascertaining the reference location has been completed (The layout will be marked bymeans of regular marking.).
・ Element tests have been conducted to verify feasibility (Confirmed that the error is ≦25mm as against the error
range of ≦50mm).
2) Verification of whether or not the PCV connection surface of the cell adapter can be processed・ Study on the method of ascertaining the shape by means of laser scanning has been completed.
・ Element tests were conducted on machining the shape of the tip of the cell adapter based on the scanner results
and its feasibility was confirmed.
（≦2.4mm as compared to the error range of ≦2.5mm),
3) Verification of the method of installing the cell adapter by remote operation
・ Study on the method of insertion and installation with respect to the PCV steel plate at the time of carrying-in thecell adapter has been completed.
・ Element tests were conducted on carrying-in and installation with the structure that is being studied , and it was
confirmed that there are no issues.
Also, the specifications required for remote operation (equipment for remote operation) were clearly specified.
4) Verification of feasibility of the boundary components
・ Element tests were conducted on carrying-in and installation with the structure that is being studied , and it was
confirmed that there are no issues in the structure.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1)(1)Development of the Method for Installing Access Equipment]

No.125① Installation of large heavy structures(6) Implementation items(6)-3-2: c. Elemental test verification of installation procedures (Organizing the required specifications of theequipment for remote installation)[Purpose]: Verification of feasibility of the side access method for large scale fuel debris retrieval based on on-site
application.
[Objective]: To clearly specify the specifications required of the equipment needed for remote operation based on the
results of the element tests at the time of carrying-in and installing the cell adapter.
Clear specification of required specifications of the equipment
1) Clear specification of the cell adapter carrying-in and installation procedures
2) Consolidating the requirements concerning the equipment with respect to the carrying-in and installation
procedures
3) Clear specification of the requirements concerning the equipment based on the results of element tests✓ Comparison with existing technologies
・ As far as possible, existing technologies are combined for the installation method.
✓ Implementation items and results
Clarification of the specifications required of the equipment based on the results of the element tests at the time ofcarrying-in and installing the cell adapter has been completed.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1)(1)Development of the Method for Installing Access Equipment]

No.126① Installation of large heavy structures(6) Implementation items(6)-3-2: c. Elemental test verification of installation procedures (Organizing the required specifications of theequipment for remote installation)✓ Contribution of the results towards the reflection destination
・ Contributes to substantiation of the procedures for installing access equipment inside the R/B for the side accessmethod.

✓ Analysis from the viewpoint of on-site applicability

・ When the structure inside the R/B of Unit 3 and test piece were simulated, although the scale was reduced to 1/2
and the weight was not simulated, the small size made handling easier, and as the environmental conditions(shape of the BSW opening / PCV steel plate, etc.) that are required for installation were simulated, it became
easier to verify workability at the site.
・ The on-site work procedures were studied, and the results were reflected when the on-site work was considered.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1)(1)Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.127(6) Implementation items(6)-3-2: c. Elemental test verification of installation procedures (Organizing the required specifications of
the equipment for remote installation)✓ Level of achievement compared to the goals[Objective]: To clearly specify the specifications required of the equipment needed for remote operation
based on the results of the element tests at the time of carrying-in and installing the cell adapter.
1) Clear specification of the cell adapter carrying-in and installation procedures
2) Consolidating the requirements concerning the equipment with respect to the carrying-in andinstallation procedures
3) Clear specification of the requirements concerning the equipment based on the results ofelement tests[Achievement status]
1) The cell adapter carrying-in and installation procedures have been clearly specified.
2) The requirements concerning the equipment with respect to the carrying-in and installation
procedures have been consolidated.
3) The requirements concerning the equipment have been clearly specified based on the results ofelement tests.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.128① Installation of large heavy structures(6) Implementation items(6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment
Other: Detailing of the work carried out inside the cellsa) Purpose of the study➢ Time required for the work such as handling the unit can inside the cells, etc. is relevantto throughput calculation.
➢ In order to enhance throughput, the work carried out inside the cells at the time of fueldebris retrieval work is detailed in an attempt to enhance the accuracy of the throughput
calculation results.
Further, in order to be able to stably carry out fuel debris retrieval work on an ongoing basis, if any of thecomponents of the fuel debris retrieval equipment fails, it needs to be exchanged early on or
maintenance needs to be carried out at the earliest, so as to be able to resume retrieval work. Therefore,
the following studies are conducted as well, as risk assessment of the fuel debris retrieval equipment.

〇 Assumption of failure mode of the components inside the cells〇 Assessment of the extent of impact on retrieval work
〇 Study of measures to prevent long-term shutdown of operation©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.129(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsb)-1 Material handling flow (Fuel debris handling line)
Shielding door

Air-tight door(+ shielding door)# Lifting up the access equipmentfrom the unit can transportation cart Fuel debris retrieval cell

Dual arm
type robot

Temporary storage

Cell adapter

Draining
equipment

Weighing scale Assignment of LLW
ID / Equipment dosimeter // dosimeterfor capturing
weighing
images inside
the can

LLW 3Dmeasurement
equipment

Fuel debris retrieval
preparatory cell

scale

Canister cell

Fuel debris retrieval cell

Double door

# Number of containers:
5 containers

Double door

Canister
Mini cask cell

Air-tight door

Surface
Water
contamination cleaning andinspection
air drying

Stand-by pit(5)

Debris transportation
cask yard# Surface contamination verification

Fuel debris transportation cask cell

Air-tight door

Unit canFuel debris transportation cask cell
Outdoortransfer

Canister

Fuel debris
transportation cask

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.130① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellsb)-1 Material handling flow (Fuel debris handling line)

Fuel debris
retrieval cell

Mini cask cell

Canister cell

Fuel debris
transportation
cask cell
Fuel debris
transportation
cask yard①

The unit can containing fuel debris is transported from inside the PCV by means of a transportation cart.

②

The unit can is grabbed by means of the dual arm type robot and is stored temporarily in a temporary storage container with a shield.

③

The unit can is removed from the temporary storage container by means of the dual arm type robot, and is placed inside the draining
equipment to drain.

④

The unit can is removed from the draining equipment by means of the dual arm type robot, and the weight and dose of the unit can aremeasured.

⑤

The unit can is lifted up by means of the dual arm type robot, the images of the inside of the unit can are captured and an ID is assigned.

⑥

The unit can is lifted up by means of the overhead crane, and is placed inside the canister via the double door.

⑦

The double door of the canister is closed by means of the MSM on the wall surface.

⑧

The canister is transported up to the opening of the connection with the canister cell by means of the transportation mechanism.

⑨

The canister is received by lifting it up from the mini cask cell by means of the overhead crane.

⑩

The second lid of the dual lid is attached to the canister and surface contamination inspection is conducted.

⑪

The canister is washed with water and air dried as required based on the results of the surface contamination inspection.

⑫

The canister is lifted up from the transportation route by means of the overhead crane and placed in the stand-by pit.

⑬

After removing the lid of the fuel debris transportation cask by means of the overhead crane, the canister is placed inside the fuel debris
transportation cask.

⑭

The lid of the fuel debris transportation cask is closed by means of a dedicated crane and the MSM.

⑮

The fuel debris transportation cask is transported up to the fuel debris transportation cask yard.

⑯

The fuel debris transportation cask undergoes various inspections to be conducted before transporting out such as inspection of external
appearance, air-tightness test, surface contamination inspection, etc.

⑰

The fuel debris transportation cask is transported to the storage preparation facility by means of the transportation vehicle.

©International Research Institute for Nuclear DecommissioningNo.131

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsb)-1 Material handling flow (Fuel debris handling line）
・Placement of equipment inside and outside the cell (Part 1)[Canister transportation route]Equipment transfer container

Maintenance cell

Fuel debris retrieval preparatory cell
Fuel debris retrieval cell
PCV

Layout drawing

Cask cell

Fuel debris retrieval cell

Mini cask cell

LLW transportation cask cell

Empty canister
Canister cell

Canister (containing fuel debris)
Canister to be decontaminated
Canister cell

Cask cell

Mini cask cell
RB wall pillar

Fuel debris retrieval cell

Fuel debris retrieval cell
Mini cask cell

Cask cell

Double door
systemMini cask cell
Canister cell

Air-tight door

Canister trolley©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.132① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsb)-1 Material handling flow (Fuel debris handling line)
・ Placement of equipment inside and outside the cell (Part 2)
MSM
Air-tight door

A

Storage pit

Overhead craneCanister
Turn table

Robot for verifying
non-contamination

A-A (Reduced drawing)

Air-tight door
Overhead craneStorage pit

BB
Decontamination Cask trap door
robot

Waste bin
MSM
Crane inside the cell

A

MSM

B-B (Reduced drawing)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]
No.133① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellsb)-2 Material handling flow (LLW # handling line)
Shielding door
#The dual arm type robot directly
enters the inner container from theaccess equipment

Fuel debris retrieval cell

Air-tight door
Fuel debris retrieval(+ shielding door)
preparatory cell

Air-tight door(+ shielding door) Maintenance cell

Dual arm type
robot

Cell adapter
Fuel debris retrieval
preparatory cell

Temporary storagedraining equipment, etc.

LLW weighing
scale / dosimeter

Air-tight door

Assignment of ID / Capturing
images of the inside of theinner container

LLW transportation cask cell

LLW canister

Water
Surfacewashing contamination
and air
inspection
dryingWaste storage container
Air-tight door
LLW transportation cask yard

LLW transportation
cask cell

Air-tight door

Waste transportation cask

#Surface contamination
verification and verificationof external appearance

Innercontainer

Outdoortransportation

Waste storage
container

LLW canister
Wastetransportation
container#LLW: Low level radioactive waste©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.134① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsb)-2 Material handling flow (LLW handling line)

Fuel debris
retrieval cell

Fuel debris
retrieval
preparatory
cell

LLW
transportation
cask cell①

The inner container containing LLW is transported from inside the PCV by means of a transportation cart.

②

The inner container is lifted up by means of the dual arm type robot, and its weight and dose are measured.

③

The inner container is lifted up by means of the dual arm type robot, the images of the inside of the unit can are captured and an ID is assigned.

④

The inner container is loaded on the transportation cart by means of the dual arm type robot, and transported to the fuel debris retrieval preparatory cell.

⑤

The inner container is hoisted by means of a jib crane, and delivered to the LLW transportation cask cell.

⑥

The LLW that is hoisted by means of the jib crane is received in the LLW transportation cask cell.

⑦

The inner container is placed in the LLW canister by means of the jib crane.

⑧

The lid of the LLW canister is closed by means of an overhead crane and MSM.

⑨

The LLW canister is hoisted by means of the overhead crane, and the contamination on its surface is inspected.

⑩

The LLW canister is washed with water and air dried at the LLW canister washing area as required based on the results of the surface contamination inspection.

⑪

After the lid of the waste storage container is opened by means of a dedicated crane, the LLW canister is placed inside the waste storage container by means of
the overhead crane.

LLW
transportation
cask yard⑫

The lid of the waste storage container is closed by means of a dedicated overhead crane.

⑬

The waste transportation cask is transported to the LLW transportation cask yard by means of the transportation cart.

⑭

The waste transportation cask undergoes various inspections to be conducted before transporting out such as inspection of external appearance, surface
contamination inspection, etc.

⑮

The waste transportation cask is loaded onto the transportation vehicle.

⑯

The waste transportation cask is transported to the solid waste storage facility, etc. by means of the transportation vehicle.
©International Research Institute for Nuclear DecommissioningNo.135

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellsb)-2 Material handling flow (LLW handling line)A

Maintenance hatch

Overheadcrane

LLW
temporarystorage box

MSM

Access door

4800
mm

LLW trolley
doorOverhead
jib crane

LLW transportation
cask yard

MSM
LLW
canister

887
mm

887
mm

Air-tight
door
Overhead craneSmeardecontaminationequipment

5525 mm

Turn table
LLW
transportation cart

LLW
transportation
cask cell

Fuel debris
retrieval
preparatory
cell

11300
mm

LLW
transportation
cask yard

MSM
Air-tight doorA

A-A (Reduced drawing)

MSM
Cask cell

LLW transportation route (from the Fuel debris retrieval
preparatory cell to the Transportation cask yard)MSM

LLW transportation
cask cell

Overhead crane

7205
mm

9845
8590 mm
mm Canister cell

Fuel debris retrieval
preparatory cell

PCV
Mini cask cell

Jib crane

Jib crane
3800
mm

2100
mm

3800
mm

Turn table
2475
mm

Waste transportation container

Smear decontamination 610 x 610 x 352 mm LLW transportationequipment
container

Air-tight
door

7725
mm

Air-tight
door
LLW transportationroute

Air-tight door

LLW transportation container

LLW transportation
container©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.136① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellsb)-3 Material handling flow (Fuel debris retrieval robot arm handling line)
Shielding door

Air-tight(+ shielding door)

Air-tight(+ shielding door)

Dual arm type robot

Access equipment(failed)Fuel debris retrieval cell

Cell adapter

Fuel debris retrieval preparatory cell

Maintenance cell

Equipment transfer container yard

Temporary storage space for theaccess equipment

Air-tight(+ shielding door)

Temporarystorage space
for the dual arm
type robot

Air-tight(+ shielding door)

Access equipment
for replacement

Verification ofmaintenance
operation

Transfer
At the time oftransfer
Equipment transfer container

Maintenance cell

Equipment transfer container©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.137① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellsb)-3 Material handling flow (Fuel debris retrieval robot arm handling line)
At the time of carrying-out

Fuel debris
retrieval cell

Fuel debris
retrieval
preparatory
cell
Maintenancecell

Equipment
transfer
containeryard①

Access equipment pulled up from inside the PCV is received.

②

The access equipment is washed with water and decontaminated.

③

The power supply cables, etc. are separated from the access equipment.

④

The access equipment is moved to the fuel debris retrieval preparatory cell by means of the remotely operated transportation equipment.

⑤

The access equipment is moved to the maintenance cell by means of the remotely operated transportation equipment.

⑥

The access equipment is washed with water and decontaminated once again.

⑦

The access equipment is placed in the equipment transfer container connected to the maintenance cell.

⑧

Equipment transfer container is separated from the maintenance cell.

⑨

The equipment transfer container undergoes various inspections to be conducted before transporting out such as inspection of external
appearance, surface contamination inspection, etc.

⑩

Equipment transfer container is loaded on to the transportation vehicle.

⑪

Equipment transfer container is transported to the maintenance facility by means of the transportation vehicle.

At the time of carrying-in
The procedures are the opposite of those mentioned above except for the following.
・ After receiving the transportation vehicle in which the required equipment transfer container is loaded, it is temporarily stored if required in theaccess equipment temporary storage space in the maintenance cell.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.138① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsb)-4 Material handling flow (Overhead traveling dual arm type robot handling line)
Shielding door

Air-tight door(+ shielding door)

Air-tight door(+ shielding door)

Dual arm type robot(failed)Cell adapter

Fuel debris retrieval cell

Dual arm typerobot forreplacement

Double door

Fuel debris retrieval preparatory cell

Maintenance cell

Failed dual arm
type robot

Access equipment
temporary storage space

Access equipment
temporary storage space

Air-tight door(+ shielding door)

Air-tight door(+ shielding door)

Replacement

To the preparatory cell

To thepreparatory cell

Maintenance

Maintenance cell (while
carrying-in for replacement)

Operationverification

Maintenance cell (while carryingout the failed components)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment] No.139① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellsb)-4 Material handling flow (Overhead traveling dual arm type robot handling line)
At the time of carrying-out
Fuel debris
retrieval cell
Fuel debris
retrieval
preparatory
cell

Maintenancecell①

The failed dual arm type robot is decontaminated to the extent possible.

②

The dual arm type robot is moved to the fuel debris retrieval preparatory cell.

③

The dual arm type robot is moved to the maintenance cell.

④

The dual arm type robot is washed with water and decontaminated once again.

⑤

The dual arm type robot is placed in the dedicated container connected to the maintenance cell.

⑥

The dedicated container is separated from the maintenance cell.

⑦

The dedicated container undergoes various inspections to be conducted before transporting out such as inspection of
external appearance, surface contamination inspection, etc.

⑧

The dedicated container is loaded on to the transportation vehicle.

⑨

The dedicated container is transported to the maintenance facility by means of the transportation vehicle.

At the time of carrying-in
The above-mentioned process is reversed and the replacement dual arm type robot is brought into the fuel debris retrieval cell.

©International Research Institute for Nuclear DecommissioningNo.140

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellsc) Heating, Ventilating and Air Conditioning System for each cell
R/B

Tent house

Flow of ventilation in each cell

Shielding door
Negative pressure area

Robot
arm
container

Dual arm
type robot
containerM

M

Air ⇔ (N2)*-200(-400)
Maintenance cell～(-50)

Exposure evaluation
Air ⇔ (N2)*-200(-400)～ (-50)Stand-by cell

M

Air

Air

-200
～ (-50)Air

M
Negative pressure (-20/-30)-200～ (-50)Air

N2
Fuel debris
retrieval cellM

-200
～ (-50)Air-200 ～
(-50)

M

-400
～ (-50)PCV-400 ～ (-50): Air-tight door
: Double door
(air-tight): Shielding door
(Not air-tight)

Inner
container

M
Waste storage
container

LLW transportation cask cell
Waste transportation cask
Canister cell
M

Fuel debris transportation cask cell

Air

Legend

M

Air

Air

Air

M

Cell adapter

Exposure evaluation

LLW
Transportation
cask cell

During normal operation

-200
Air
-200
Air ～ (-50)

MM

UC (with hole atthe bottom): Exhaust
Canister-200～ (-50)Mini cask cell

(N2)*
-300
～ (-50): For controlling
N2 oxygen concentration
M : Monitoring: Fuel debris
: LLW

Air⇔
M

: Air supply

・ Exposure assessment:
The extent of impact of the radiation and radioactive
materials radiated, emitted from the reactor is assessed.
It is confirmed that the effective dose received by the
public in the areas in the vicinity of the site is lower than
50μSv per year.

・Air⇔ (N2)*: With nitrogen purging function.

・ Numerical values are provisional©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.141① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsd) Risk assessment (1/4)➢

The risks assumed in each cell are identified, and their exposure impact and impact on the work schedule are studied.
Also, their countermeasures are studied.
： Probability / impact is low： Probability / impact is highRisk

Initiatives in response to the risks

Target area（✓: Applicable, －： Not
applicable）
Probability of occurrence(Reasons)

Exposure impact(Public)

Exposure impact(Workers)

Impact on work schedule

Prevention

Mitigation of the impact
upon occurrence－―(Generated due to normal
work)

Small
(The impact is small as aconfinement effect is
expected due to the cellboundary)Same as on the left―
(Due to normal operation）ーControlling negative
pressure inside the cell－―
(Generated due to normal
work)

Small
(The impact is small as aconfinement effect is
expected due to the cellboundary)Same as on the left―
(Due to normal operation）ーControlling negative
pressure inside the cell,collecting dust by
installing a local
exhauster in the peripheryof the draining equipment－

Low(The probability ofoccurrence is low as
failure of the exhaust fan
or loss of power supply,
etc. are causes and thus
multiple preventive
measures areconceivable)

Large(If events associated withdust dispersion such as
falling of the unit can orcanister, etc. overlap,
dusk is likely to leak froma route that does not go
through a filter due to
shutdown of the exhaust
fan.)

Large
(If events associated withdust dispersion such as
falling of the unit can orcanister, etc. overlap,
dusk is likely to leak froma route that does not go
through a filter due to
shutdown of the exhaust
fan.)

Large
(The impact is small if theequipment can berestored by remote
operation or by manner
operation outside the cell.
If large scale work such as
equipment replacement,
etc. due to equipment
failure, etc. needs to be
carried out, a major delayin schedule is expected.)

Using a design in which
multiple exhaust fan
systems are installed andin the event of an
emergency, nitrogen
supply stops by means ofan interlock, etc.

Stopping nitrogen supply
to the cell－

Low
(There is no leakage aslong as the static
confinement function is
not lost, since this iscaused by aging
degradation due to longterm use)

Large
(If events associated withdust dispersion such as
falling of the unit can orcanister, etc. overlap,
dusk is likely to leak froma route that does not go
through a filter due to
shutdown of the exhaust
fan.)

Large
(If events associated withdust dispersion such as
falling of the unit can orcanister, etc. overlap,
dusk is likely to leak froma route that does not go
through a filter due to
shutdown of the exhaustfan.)Large (The impact is small
if the equipment can berestored by simple
operations such as
replacement ofcomponents, etc. If large
scale work needs to be
carried out due to failureof the seal part, etc., amajor delay in schedule isexpected.)

Retaining the confinement
function by increasing thequantity of exhaust or
reinforcing the boundary,
if a drop in air-tightness is
detected when the extent
of negative pressure in
the cell is monitored.

ーAssumed events and causes

Leakage of dust from aroute that does not go
through a filter, as a partof the boundary isdamaged due to aging
degradation of the seal
part

✓

✓

✓

✓

✓

✓

－

✓

✓

✓

✓

✓

Fuel debris
transportation
cask yard
Fuel debris
transportation
cask cell

Loss of static
confinement function

Leakage of dust from aroute that does not go
through a filter, as thenegative pressure inside
the cell is lost when theexhaust fan stops.

Canister cell

Loss of dynamic
confinement function

Mini cask cell

Dispersion of dust
associated with draining
the fuel debris or canister

FDR Cell

Risks during normal
operation

Dispersion of dust fromthe surface contaminationof the vessel or fuel debris
while handling unit cansor canisters

－

－

－

－

©International Research Institute for Nuclear DecommissioningNo.142

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside thecells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsd) Risk assessment (2/4)： Probability / impact is low

Risk： Probability / impact is highInitiatives in response to the risks

Target area（✓: Applicable, －： Not
applicable）
Probability of occurrence(Reasons)

Exposure impact(Public)

Exposure impact(Workers)

Impact on work schedule

Prevention

Mitigation of the impact
upon occurrence－

Low(The effect of the methodof draining is verified bymeans of mock-up tests,
etc.)

Small
(Since this is mostly afterdraining, it can almost be
ignored, and hence theimpact is small)

Large(If the abnormality needs
to be restored by manned
operation, the exposure
impact on the personnel
is likely to be significant.)

Small(Large quantity ofradioactive material isunlikely to be released.)

Studying methods, etc.
for adequately draining
the canister

Controlling negative pressure
inside the cell－

Low
(Large quantities ofcontaminated water being
generated and thecontainer or pipes getting
damaged due to it is arare occurrence.)

Small(The impact is small since
the quantity ofcontaminated water
generated as a result ofdraining is believed to besmall.)

Large(If the abnormality needs
to be restored by manned
operation, the exposure
impact on the personnel
is likely to be significant.)

Large(The impact is small if theequipment can berestored by remote
operation or by manned
operation outside the cell.
The impact is large if
large scale work such as
equipment replacement,
etc. due to equipment
failure, etc. needs to be
carried out.)

Regularly verifying the
integrity of the pipes orcontainers for collecting
contaminated water

Controlling negative pressure
inside the cell－

High
(This is an event thatwould occur due to failureof stand-alone equipment
constantly used during
the fuel debris retrieval
period. Hence theprobability of occurrence
is comparatively high.)

Small(The impact is small as
the public is at a sufficientdistance from the siteboundary.)

Large(If the abnormality needs
to be restored by manned
operation inside the cell,
the personnel is likely to
get exposed.)

Large(If the equipment cannot
be restored from outside
the cell, methods forrestoring the equipment
need to be studied. Hencea major delay in schedule
is expected.)

Adopting a design thatenables collection of fueldebris without entering
the cell in the event ofabnormal shutdown ofequipment, anddeveloping procedures
for remotely restoring theabnormality

ー

－

High
(This is an operation thatis repeatedly carried out
during the fuel debris
retrieval period. Hencethe probability ofoccurrence is high.)

Small(The impact of external
dose is small as the
public is at a sufficientdistance from the siteboundary.)

Large(Personnel present in thevicinity of the cell is likely
to get exposed.)

Large(The impact is small if theequipment can berestored by simple
operations. If thecontainer gets damaged
and cannot be restored, amajor delay in schedule isexpected.)

Studying means toremotely verify whether
the lid of the container isheld securely

Installing auxiliaryshielding

Assumed events and causes

The shielding door isstuck open thus making
restoration impossible.

✓

✓

－

－

✓

✓

－

Fuel debris
transportation
cask yard
Fuel debris
transportation
cask cell

The pipes or containers inwhich contaminated water
resulting from washing
the canister is collected
get damaged, leading toleakage of contaminatedwater.

－

Canister cell

Leakage ofcontaminated water✓

Mini cask cell

FDR CellContaminated water leaks
due to inadequate
draining after washing thecanister with waterleading to spread ofcontamination

－

－

－

Loss of shielding
function
The lid of the container
which is expected toshield fails to close, andhence the unit can, etc.
cannot be appropriately
contained leaving it
exposed.

✓

－

✓

－

©International Research Institute for Nuclear DecommissioningNo.143

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsd) Risk assessment (3/4)： Probability / impact is low： Probability / impact is highRisk

Initiatives in response to the risks

Target area（✓: Applicable, －： Not
applicable）
Probability of occurrence( Reasons)

Exposure impact(Public)

Exposure impact(Workers)

Impact on work schedule

Prevention

Mitigation of the impact
upon occurrence－High(This is an operation thatis repeatedly carried out
during the fuel debris
retrieval period. Hence theprobability of occurrenceis high.)

Small(The impact is small as thenegative pressure inside
the cell is controlled andconfinement is expectedfrom the cell boundary.)

Small(Since the negative
pressure inside the cell is
controlled, the personnel
in the area around the cell
hardly get exposed.)

Large(If the fuel debris that has
fallen from outside the cellcannot be collected,
methods for restoring theequipment need to bestudied. Hence a majordelay in schedule isexpected.)

Studying means toremotely verify whether
the unit can, etc. is held
securelyControlling negative
pressure inside the cell－

High
(This is an operation thatis repeatedly carried out
during the fuel debris
retrieval period. Hence theprobability of occurrenceis high.)

Small(The impact is small as thenegative pressure inside
the cell is controlled andconfinement is expectedfrom the cell boundary.)

Small(Since the negative
pressure inside the cell is
controlled, the personnel
in the area around the cell
hardly get exposed.)

Large(If the fuel debris that has
fallen from outside the cellcannot be collected,
methods for restoring theequipment need to bestudied. Hence a majordelay in schedule isexpected.)

Studying means toremotely verify whether
the heavy weight object isheld securely

Controlling negative
pressure inside the cell

Large
(If the transportation cask
gets damaged due to theimpact, a large amount of
dust is likely to getdispersed, but if the cask
remains intact it can be
expected to provide
confinement.)

Large(If the transportation cask
gets damaged due to theimpact, methods forrestoring it need to bestudied. Hence a majordelay in schedule isexpected.)

Setting a limit to the rateof acceleration of thetransportation cask forpreventing collision andfallーAssumed events and causes

Abnormality in fueldebris cooling
function－✓✓

Fuel debris
transportation
cask yard
Fuel debris
transportation
cask cellOccurrence of
criticality✓✓

Canister cell

Increase in activity
concentration (dustdispersion)

Heavy weight objects fallon top of fuel debris andthe impact causes dust
dispersion✓

Mini cask cell

FDR Cell

Dispersion of the contents
and adhered contaminants
when the unit can, etc.
falls or tumbles－－

Dispersion of contents ofthe fuel debris
transportation cask when
it falls as a result of
coming in contact withsurrounding structures,
etc.

－

－

－

✓

✓

High
(This is an operation thatis repeatedly carried out
during the fuel debris
retrieval period. Hence theprobability of occurrenceis high.)ー(The shape of thecontainer is controlled
and hence the possibilityof criticality is ruled out.)

－

－

－

－

－

－

－

－

－

－

－

ー
(Forced cooling is not in
the scope of assumptions
for a unit can or canister)

－

－

－

－

－

－

－

－

－

－

－

Same as on the left

©International Research Institute for Nuclear DecommissioningNo.144

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside thecells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsd) Risk assessment (4/4)： Probability / impact is low

Risk： Probability / impact is highInitiatives in response to the risks

Target area（✓: Applicable, －： Not
applicable）

Probability of occurrence( Reasons)

Exposure impact(Public)－

Low(The probability ofoccurrence is low because
the event can be prevented
by stopping acceptance offuel debris from the PCV
when an abnormality isdetected and transferring
the fuel debris from inside
the cell to the outside)Large(If the boundary getsdamaged due to the fire /explosion, the radioactivity
inside the cell is likely to
get dispersed to theoutside.)✓Low(The probability ofoccurrence is low as thisoccurs when there is an
overlap of insufficientdrying and loss ofhydrogen emissionfunction on the containerside.)－High(This is an event thatwould occur due to failureof stand-alone equipment
constantly used during thefuel debris retrieval period.
Hence the probability ofoccurrence iscomparatively high.)－

High(This is an event thatwould occur due to failureof stand-alone equipment
constantly used during thefuel debris retrieval period.
Hence the probability ofoccurrence iscomparatively high.)

Assumed events and causes

The equipment related tomaterial handling such as
dual arm type robot, crane,transportation cart, etc.
cannot be restored as they
have shutdown abnormally

－

✓

✓

✓

✓

✓

✓

✓

Fuel debris
transportation
cask yard
Fuel debris
transportation
cask cell

Fire and explosion
inside the container

The container continues toremain sealed due toinsufficient drying of fueldebris, and theconcentration of hydrogen
inside the container
reaches the inflammability
limit (4%) leading tohydrogen combustion.

✓

Canister cell

Maintaining the nitrogen
atmosphere isunsuccessful, leading tohydrogen combustion andmetallic fire

Mini cask cell

FDR Cell

Stopping of nitrogen
supply(Fire and explosion
inside the cell)

－

✓

－

Unrestorable due toequipment shutdown

Failure of other equipment

✓

－

✓

－

Exposure impact(Workers)

Impact on work schedule

Prevention

Mitigation of the impact
upon occurrenceSame as on the left

Large
(A major delay in the work
schedule is expected due
to restoration of thedamaged cells or
equipment, investigationof cause, recurrence
prevention, etc.)

Adopting a design inwhich multiple nitrogen
supply systems that stop
working until restoration
are installed so as toenable switching over tostand-by systems, etc. in
the event of an emergency

Extinguishing fire bymeans of firefighting
equipment in the event of a
fire

Large
(If the boundary getsdamaged due to the fire /explosion, the radioactivity
inside the cell is likely to
get dispersed to theoutside.)Same as on the left

Large
(A major delay in the work
schedule is expected due
to restoration of thedamaged cells or
equipment, investigationof cause, recurrence
prevention, etc.)

Sufficiently drying the fueldebris and verifying it

Extinguishing fire bymeans of firefighting
equipment in the event of a
fire

ー

Large
(If the abnormality needs
to be restored by manned
operation inside the cell,
the personnel is likely to
get exposed.)

Large(If the equipment cannot
be restored from outside
the cell, a major delay inschedule is expected.)

Adopting a design thatenables collection of fueldebris in the event ofabnormal shutdown ofequipment, and developing
procedures for remotely
restoring the abnormality

ー

ー

Small
（Restoration by means ofmanned operations inside
the cell is likely to become
necessary, but personnel
exposure can be kept
adequately down byentering after the inside of
the cell isdecontaminated.)

Small(Since manned operation
can be carried out inside
the cell by transferring fueldebris from the cell anddecontaminating the insideof the cell, it is believedthat there is little impact
on work schedule.)

Periodic integrity
verification of theequipmentー©International Research Institute for Nuclear DecommissioningNo.145

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval
equipment✓ Other: Detailing of the work carried out inside the cellse) Restoration when the equipment is shutdown (mini cask cell and canister cell)(1) Maintenance and repairs (inside the cell)
Equipment used
Cell

Mini cask cell

Canistercell№

Equipment name

Failure mode

Maintenance method

・ Separating the actuator installed outside the cell・ Moving it to the maintenance facility and carrying out maintenance

Remote MSM

Overhead crane

―

―

―

―

✓

#

1

Canister trolley

Failure of actuator

Etc.

2

Canister hoisting equipment

Failure of actuator

Etc.

3

Double door system

Regular replacement

4

Overhead crane(Storage pit area)

―

―

―

―

5

Crane inside the cell
(Decontaminated area)

―

―

―

―

6

Remote MSM

・ Removing the slave arm from the cell wall surface

#

✓

7

Air-tight door
(Between the storage pit area andthe decontaminated area)

・ Replacing the door by means of the remote MSM (replacing the packing)

✓

#

8

Canister turn table

―

―

9

Robot for verifying noncontamination

Failure of detector

・ Removing the cable connector of the detector

✓

#

10

Decontamination robot

Failure of decontaminator・ Removing the decontaminator

✓

#

11

Cask trap door

・ Replacing the sealant✓#

Slave arm failure

Regular replacement

・ Moving up to the collection location and transferring using the external drive shaft(There are 2 actuators)

・ Replacing the door by means of the remote MSM on the fuel debris retrieval cell side―

Regular replacement―# indicates that providing support as required from the perspective of improving work efficiency is considered.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.146① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellse) Restoration when the equipment is shutdown (mini cask cell and canister cell)(2) Maintenance and repairs (outside the cell)
Cell

Mini cask
cellCanistercell№

Equipment name

Failure mode

Maintenance method―

1

Canister trolley

2Canister hoisting equipment

―

―

3

Double door system

―

―

4

Overhead crane(Storage pit area)

Failure of actuator

・ Replacing the actuator from the ceiling (There are 2 actuators)

5

Crane inside the cell
(Decontaminated area)

Failure of actuator

・ Replacing the actuator from the ceiling (There are 2 actuators)

Failure of drive module

・ Separating the arm connecting part from the suspension arm of the drive module using
the hoist
・ Loading on the dedicated cart
・ Moving it to the maintenance facility and carrying out maintenance

―

―

6

Remote MSM

7

Air-tight door
(Between the storage pit area andthe decontaminated area)

8

Canister turn table

Failure of rotary actuator・ Removing and replacing the actuator (There are 2 actuators)

9

Robot for verifying noncontamination

Failure of actuator Etc.

・ Removing and replacing the actuator (There are 2 actuators)

10

Decontamination robot

Failure of actuator Etc.

・ Removing and replacing the actuator (There are 2 actuators)

11

Cask trap door

Replacement of the drive wire

・ Replacing the external actuator (There are 2 actuators)

In principle, maintenance and repair work is carried out by workers.
©International Research Institute for Nuclear DecommissioningNo.147

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipmen✓ Other: Detailing of the work carried out inside the cellsf) Dust evaluation (1/3)
A conceptual study on the method of making an opening in the BSW concrete and the method of cutting the X-6 penetration has been conducted, but since dust is likely toflow into the gap between the BSW and the PCV steel plate while making an opening in the BSW concrete, the inflow of dust is evaluated.
[After internal investigation or after installing the shieldingdoor]① Releasing the X-6 penetration flange and sealing thepenetration(Work inside the isolation chamber)[During the PCV internal investigation]
Releasing the X-6 penetration flange andremoving deposits (Work inside the isolationchamber)

Isolation chamber

BSW

10. Making an opening in BSW concrete(Work inside the isolation facility for making the opening)

Shieldingdoor

TemporaryshieldingGreenhouse

Isolation chamber
Equipment for
remoteoperation

X-6 penetration
BSW
Conceptual drawing

Air-tightness is ensured
using the filler material

X-6 penetration
Penetration sealing equipment

Already sealed andisolated using the filler
material

Washing the inside of the X-6 penetrationand pouring filler material

Deposit removal equipment

Pipe arm(Hose)

Greenhouse

Filler material
Installation tool Inlet for pouring geopolymer (Low viscosity)
Approx. 2.3m

Geopolymer reagent

Baffle board ①

BSW
Penetration
plug

Penetration
plug

Cutting

Removing deposits from inside theX-6 penetration

X-6 penetration

Air line connecting port

Filler material
X-6(High viscosity)
Cross section of the penetration(# This topic is studied during
X-6 penetration while
in-house research)
it is being closed

PCV steel plateX-6 penetration
Closingplate

Air line
Compressor

Core boring(Example of method ofmaking an opening)

Cutting

Reducing the length of X-6
penetration (plane surface)

Reducing the length of X-6
penetration (3D image)

Procedure
Issues

An isolation chamber is set up and if any
deposits (cables, etc.) remain inside thepenetration, they are removed.

An isolation chamber is set up for sealing the X-6 penetration,and the inside of the penetration is washed.
After washing, the X-6 penetration and the inside of the PCV
are isolated by pouring filler material (Geopolymer, etc.).

The cell for making the opening is installed, and an opening is made in the BSW.
Also, the length of the X-6 penetration is reduced and a closing plate is installed.

・ Study of substantiation of the timing of the
PCV internal investigation and the contents of
the investigation

・ Substantiation of the method of sealing the X-6
penetration using filler material
・ Contamination control during work

Tentative cell specifications for the work of making the opening
・ Measures against outflow of dust into the gap between the BSW and the PCV©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.148(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsf) Dust evaluation (2/3)
In order to evaluate the exposure impact on workers due to generation of dust during the work of making an opening in the BSW, thequantity of dust outflow from the Reactor Building was evaluated and the amount of worker exposure was evaluated.

Flow analysis

Evaluation of gas flow and dust trajectory(Dust behavior)Amount of outflow of dust from the Reactor
Building＝ Amount of cutting x rate of dispersion ＊ x
gas phase transition rateGas
flow line
ガス流線

X-53ペネ
X-53 penetration
Reactor原子炉
building
建屋Transition rate = Amount of outflow from
移行率＝原子炉建屋流出量
Reactor
Building / Gas phase mass
(Flow analysis)/ガス相質量（流動解析）
Rate of dispersion = Gas phase mass /飛散率＝ガス相質量/切断量
Amount of cutting(Test result)（試験結果）

X-53
penetration
X-53ペネコアドリル
Core drill

100㎜Core drill
コアドリル（ダスト発(generationof dust)生）
Φ200mm、 204rpm

Dust dispersion
ダスト飛散

X-6ペネ
X-6 penetration

Core boring tool
コアーボーリングツール

PCV

X-6 penetration
X-6ペネ

Analysis method• 解析方法The penetration part is simulated up to the Reactor
・解析モデルは貫通部原子炉建屋側までを模擬
Building side in the Analysis model＊: Dust dispersion rate (From the outcome of the Subsidy Project of Upgrading ofFundamental Technology for Retrieval of Fuel Debris and Internal Structures under the• ・最初の開口作業を想定
The initial work of making an opening is assumed“Subsidy Project of Decommissioning and Contaminated Water Management” in the
FY2016 Supplementary Budgets)• The core drill is rotated until it completely passes through・コアドリルはアニュラス部に全貫通回転
Rate of dispersion
the annulus part
Collected dust (mg)(%)
StandSurface part• ・コアドリルで誘起されるガス流れ場計算
The gas flow field induced by the core drill is calculated
alone
Intermediate part• ・コアドリル表面から、密度、直径を有するダスト
Dust having density and size is generated from the corehole
Posterior part (PCV side)
drilled surface and its trajectory is calculatedを発生し、軌跡を計算
Connecting
Surface part
• The transition rate of the dust flowing out from the Reactor
holes
・原子炉建屋に流出するダスト移行率を評価
Intermediate part
Building is evaluated
BSW

Annulus part
アニュラス部(Gas phase)
（ガス相）

X
53
閉
鎖

Closing X-53 penetration

ガス流速
Gas
flow rate
[m/s]
[m/s]

Reactor
原子炉
配管貫通部
penetration partbuilding
建屋 PipeSurface
表面汚染度
contamination(General
information)（一般情報）(Flow analysis results)(Flow analysis model)

3,0.4μｍ)
Dustダスト軌跡(2460kg/m
trajectory (2460kg

Outflowfrom X-13A and X101B penetrations
X-13A、X-101Bペネ流出

X-53 penetration
X-53ペネ閉鎖
closed
Core
drill
コアドリル
Core drill
コアドリル

Rate of transition of dust to the gas phase(Density 2460kg/m3)
X-53
Not closed
closed4 locations
closedGas phase transition rate①

Dust size

Posterior part (PCV side)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.149① Installation of large heavy structures(6) Implementation items (6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cellsf) Dust evaluation (3/3)② Reactor Building dust outflow rate evaluation✓

The Reactor Building dust outflow rate (g/g) is evaluated basedon the dust dispersion rate, particle size distribution, and the gas
phase transition rate for each particle size, when 1g BSW is
scraped.
There are 2 kinds of particle size distributions and many kinds ofdispersion rates, but large, medium and small dispersion rates
are identified, and the Reactor Building dust outflow is evaluated.
The Reactor Building dust outflow rate is the maximum atapprox. 1×10-4 when the penetrations are not closed, and it isequivalent to 2×10-6 when the penetration parts are closed.

✓✓③ Reactor Building dust exposure evaluation[Exposure evaluation method and conditions]• Based on the CFD analysis results, the Reactor Building outflow rate of radioactive dust generated while
making an opening in the BSW (= Quantity of radioactive dust that has dispersed from the opening andflown into the R/B / Amount of radioactive material present within the range of the opening) is set at 1.0E-03% assuming the case when the X-53 penetration is closed.
• Other conditions are set while referring to the Fukushima Daiichi Nuclear Power Station Specified Nuclear
Facilities Implementation Plan [1] (hereinafter “Implementation Plan”) and the “Hand-book on Environmental
Impact Assessment for Decommissioning Work (Third Edition)”[2] （hereinafter , “Decommissioning handbook), etc.
Unit
単位

Value
値

Bq/cm2

Cs＊1：8.5E+06
Pu＊1：2.1E+05

Opening space
開口面積

cm2

314.2

Area
corresponding [1]to より、コアカッターの直径（20the diameter (20 cm) of the core
補助事業報告書
cutteraccording to the Subsidy Project Reportcm）に対応した面積

Rate of outflow of radioactive
放射性ダストのwaste into the R/B (2)
RB内への流出率②%

1.0E-03

Set based on the CFD
CFD解析結果に基づき設定
analysis
resultVolumeof the work area in R/B
RB作業区画体積m3

825

6.9E-05

Gamma rays effective
γ線実効エネルギ
energyMeV

Cs＊1：5.97E-01
Pu＊1：1.73E-03

From the Decommissioning[2][3]
廃炉ハンドブックより
Hand-book[2]

2.2E-06

Internal exposure dose
内部被ばく
conversion coefficient
線量換算係数

mSv/BqCs＊1：3.9E-05
Pu＊1：1.2E-01

From the Decommissioning[2][3]
廃炉ハンドブックより
Hand-book[2]

Rateof respiration
呼吸率

m3/h

1.2

Rate of respiration during activities
成人活動時の呼吸率
undertaken
by an adult

Exposure reduction effect
マスクによる被ばく低減効
due to the mask (DF)
果（DF）

－

50

Assuming that a full face
全面マスクの着用を想定
mask is worn

Item
項目

汚染密度① density (1)Contamination
X-53 penetration closed: Surface part

No closed penetrations: Surface part閉鎖ペネ無：表層部粒径分布
particle
size distribution

X53ペネ閉鎖：表層部粒径分布
particle size distribution

44貫通部閉鎖：表層部粒径分布
penetrations closed: Surface part particle
size distribution

No closed penetrations: Intermediate part閉鎖ペネ無：中間部粒径分布
particle size distribution

X-53
penetration closed: Intermediate part
X53ペネ閉鎖：中間部粒径分布
particle size distribution

4 penetrations closed: Intermediate part
4貫通部閉鎖：中間部粒径分布
particle size distribution

Remarks
備考

Building dust outflow rate
Reactor
原子炉建屋ダスト流出率g/g

1.0E-03
1.0E-04
6.9E-06

1.0E-05

1.0E-06

2.2E-07

7.4E-08

3.9E-07

1.0E-07
3.9E-08
1.0E-08
1.0E-09

2.4E-09[2]で想定されているRB区画体積[1]
Volumeof the work area
in R/B as assumed in the Unit 2
2号機の実施計画
Implementation
Plan [1] (1/4 area on the first floor)（1階部の1/4区画）【 Evaluation results】• The exposure is 2.3E-03 mSv/h with a mask and 1.2E-01 mSv/h without a mask. Thus it is believed that the exposure
impact on workers resulting from outflow of radioactive dust into the R/B during the work of making an opening in the
BSW is small.

4.2E-101.0E-101.0E-05

Set
based on the[1]Subsidy
補助事業報告書より設定
Project Report

1.0E-04

1.0E-03

1.0E-02

飛散率
Dispersion
rate％

1.0E-01

1.0E+00

Unit
単位
External
exposure
外部被ばくInternal
exposure
内部被ばく
Total
合計

mSv/h

線量率
Dose rate(with mask)（マスクあり）
1.4E-07
2.3E-03
2.3E-03

線量率
Dose rate(without mask)（マスクなし）Same同左as the left
1.2E-01
1.2E-01©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.150① Installation of large heavy structures(6) Implementation items[Tests related to PCV welding equipment for remotely welding the flange part]Approach towards ensuring functional requirements
Equipment class, safety functions○

Non-class (Set based on the current conditions when there is no power generation facility)○

Air-tightness for maintaining negative pressure (During normal times, in the event of an earthquake)

Studies are conducted taking into account ensuring and maintaining safety functions by remote welding operations

・ Structure that enables work
under restricted conditions
such as confined spaces,
remote operation, etc.
・ Ensuring air-tightness

Ensuring welding quality
・ Appropriate installation conditions
・ Strength properties of thematerials
・ Improvement in welding skills

・Verification of welding
quality・Verification of air-tightness
・Verification of the strength
for withstanding load

Reduction and elimination[Structure]○ Fillet welding on one of theinner sides
・ TIG welding○ Structural evaluation by meansof stress analysis
・ Self weight + pressure +seismic force[Welding]○ Verification of welding conditions
Full-scale partial model test
Considering confined space,groove gap, PCV curve, position, etc.
PCV material and welding joint test
Considering the impact of heaton PCV○ Establishment of welding repair
methods○ Welding verification (full size)○Improvement in welding skills throughwelding tests[Inspection]○ Before welding
・ Inspection of external
appearance
・ Inspection of the groove(gap inspection)○ After welding
・ Inspection of external
appearance(・ Leak test （air-tightness))・ Pressure resistance test
(strength)[Other]○ During welding: Workmanagement[In-service monitoring]○ Pressure inside the cell
adapter
・ Maintenance ofnegative pressure
・ Detection of defect in
air-tightness○ Veriication of external
appearance
・ Corrosion leading to
defect in air-tightnessof risks through long-term
use©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.151① Installation of large heavy structures(6) Implementation items(6)-4: d. Detailing of the work carried out inside the cells of the fuel debris retrieval equipment✓ Other: Detailing of the work carried out inside the cells✓

Level of achievement compared to the goals•

The work, equipment and work flow for each of the following items to be handled during the work inside
the cells in the fuel debris retrieval equipment has been consolidated in the material handling flow
diagrams.
〇 Fuel debris〇 LLW〇 Robot arms for fuel debris retrieval〇 Overhead traveling dual arm type robot•

The heating, ventilating and air conditioning system inside the cell was studied based on the items to behandled inside the cells and their form, and considering that the inside of the cell needs to basically havenegative pressure from the viewpoint of confinement, that spread of contamination needs to be prevented,
that the atmosphere and environment inside the cells is the same as the PCV as the cells are connectedto the PCV, etc. Specifically, the flow of air supply/exhaust, type of atmospheric gas inside the cells andthe monitoring position were studied.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1)(1)Development of the Method for Installing Access Equipment]

No.152① Installation of large heavy structures(7) Summary➢ The structure was detailed focusing on the boundary (connected parts, assembled parts and installedparts) of the cell adapter, shielding door and fuel debris retrieval cell that form the access equipment.
➢ The access equipment and other fuel debris retrieval equipment cells need to be installed accurately
in a straight line between the pedestal opening and the X-6 penetration opening, in order to establish
the shortest access route.
Hence, the installation procedures and structure were studied, and proposals on the structure andinstallation feasible on the whole were developed considering the fitting accuracy.
➢ As a part of the study for enhancing throughput, the work carried out inside the cells was detailed for
improving the accuracy of the results of calculating throughput.
➢ The work steps involved in installing large heavy structures were detailed and revised, issues in eachstep were identified, and element tests (establishment of the installation reference location, verificationof the 3D processing technique for the cell adapter flange, verification of whether or not insertion ispossible, and overall structure) for determining the policy for responding to the issues and for verifying
it were designed and conducted.
➢ Since the work of installation will be carried out under high radiation dose environment, the cell
adapter will need to be installed by remote operations. Hence the detailed steps involved in the
installation procedure were organized and related isuues were consolidated. Also, a test plan forclarifying the required conditions for the remotely controlled equipment was created based on a
structure that was substantiated and the tests were conducted.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.153② PCV connection sleeve installation and welding by remote operation
Studies have been conducted related to ensuring air-tightness of the connected parts for accessing
the inside of the PCV for the purpose of further increasing the scale of retrieval of fuel debris andreactor internal structures. Technology is required that enables accurate installation of equipment
such as the sleeve, etc connected to the PCV, by remote operation under work environment andinstallation conditions that include high radiation and confined spaces, etc., thereby securing theconfinement function of the connected parts.
The requirements for installation of the sleeve, etc. connected to the PCV by remote operation will
be consolidated, the method of installation by remote operation, the equipment and devices, andprocedures will be studied, and element tests will be planned and implemented using simulated test
pieces, and feasibility of the requirements such as accuracy assessment, etc. will be verified. The
connection method considering the possibility of the PCV side being deformed will be studied. Also,
the study will take into consideration the acceptable maximum load on the R/B floor.
The requirements for welding, inspecting and maintaining the sleeve, etc, as the technology for
confining the connected parts will be consolidated, and the method of implementing a series ofoperations such as welding procedures, inspection and maintenance by remote operation, including
the development of methods considering accuracy of installation by remote operation, remotewelding equipment and required tools, pre-processing such as polishing before welding, will be
studied. Thereafter, verification tests using simulated test pieces will be planned and implemented,
and the welding efficiency and viability of the requirements will be verified.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.154② PCV connection sleeve installation and welding by remote operation

Table of Contents
⚫
⚫
⚫
⚫
⚫

Overview of the access tunnel
Development results related to the access tunnel achieved so far and correlation with this projectStatus of studies conducted up to FY2020
Issues, implementation details and results
Outline of procedures while using the actual facility(a) Installation by remote operation⚫ Requirements⚫ Selection of remote installation equipment⚫ Full view, motion axis, overview of installation steps⚫ Installation procedure⚫ Simulation scope⚫ Mock-up equipment structure⚫ Comparison with actual facility⚫ Test plan, test flow
⚫ Measurement correlation diagram⚫ Test results, issues⚫

(b) Welding⚫ Test plan, test results
1) Welding test
2) Abrasion test3) Fluorescent PT test4) Dimension measurement
5) Cold crack test
⚫ Summary of test results

Development schedule, summary©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]② PCV connection sleeve installation and welding by remote operation

No.155Additional
増設建屋
building

Overview of access tunnel is provided below.
[Concept of the method]• A method that does not apply any load on the R/B floor considering
the load capacity of the R/B floor

PCV[Overview of the method]
Access tunnel
アクセストンネル① The access tunnel is installed by delivering it from outside the R/B.
② The load is supported by the R/B wall and the floor surface of the BSW opening.
(Note) Connecting the access tunnel to the equipment hatch is being planned (common for Units 1 - 3)(Note) Load bearing of the R/B wall and the floor surface of the BSW opening: 750ton/m2, load bearing of the R/B_1F
floor surface: Approx.4.9ton/m2[Developmental challenges]① Feasibility of the delivery method→ Verification of the feasibility of the delivery method by simulating the shape (Implemented in FY2018)
Verification of feasibility of the rotating part by simulating the mass (Implemented in FY2020-21: Ensuring
Safety PJ)② With 1800mm thick BSW, the load needs to be supported and displacement in the event of an earthquake needs
to be absorbed.
→ Verification of feasibility of displacement absorption mechanism (Implementation in FY2020-21: Ensuring
Safety PJ)
Study of installing and welding the sleeve, etc. (This project)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.156② PCV connection sleeve installation and welding by remote operation
Development results related to the access tunnel achieved so far and correlation with this project are indicated below.
Method & Systems Upgrade (Implemented in FY2017-18)[Verification of the feasibility of the method (conducting element tests
related to shape, dimensions, scale)]➢
Delivery of tunnel path➢
Delivery of the curved surface tunnel through the narrow opening➢
Remote work monitoring, positioning accuracy

Biological shield opening
Access tunnel

DeliveryAccess tunnel(actual outer appearance)

Location of R/B
outer wall
SleeveAccess tunnel
Displacement absorption
mechanism

Further Increasing the Scale of Retrieval (Implemented
in FY2019- 20)
Sleeve[Verification of the connection method]➢
Study of issues identified above➢
Method of connecting to the BSW (sleeve welding
test)➢
Study of sleeve (displacement absorption
mechanism) structure

Implemented in this project[Verification of feasibility looking ahead at the actual
facility]➢
Study of the method of remotely installing andwelding the sleeve (Verification at full scale)➢
Addition of shield and disassembly of shield plug
Items to be studied in future➢

Study of developmental challenges identified during engineeringand technical development, etc.

Load support
point

Slide part
Load support
point

Ensuring Safety (Implementation in FY2020-21)[Verification of feasibility through testing]➢
Delivering heavy weight objects (Verification of theslide part)➢
Displacement absorption mechanism (Verificationof quantity of leakage)]

Displacement absorption
mechanismApprox.
1800mm

Displacement
absorption mechanism

PCV connection
sleeveOutsourced to TEPCO HD (Implemented in FY2020-21)[Study of the concept of the equipment for remotely
installing the PCV connection sleeve]➢
Selection of proposal for remote installation ofsleeve➢Conceptual design and identification of issues

Welding

PCV (equipment
hatch)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.157② PCV connection sleeve installation and welding by remote operation[Status of studies conducted up to FY2020]<PCV connection sleeve welding>⚫ Consolidation of welding conditions of equipment hatch shell and PCV
connection sleeve⚫ Welding element test (Verification of gap that can be welded)⚫ Selection of abrasive
Illustration of the PCV connection
sleeve installation (Unit 3)⚫ Study of grinder (Implementation of prior verification test)⇒ It was confirmed through the element test on welding that a gap of 20mm can be welded as well.
Full scale welding test (full scale mock-up test) is implemented based on the welding element tests
conducted up to FY2020.
Further, the gap needs to be reduced as much as possible considering the on-site workability, thermal
contraction effect at the time of welding, and quality.
A prototype of the installation equipment will be manufactured to verify the accuracy of full scale remote
installation of the sleeve connected to the PCV.
Implemented in this project

Testing by setting conditions
Gap

Gap
Flat plane(t=12)

Flat plane(t=90)✓ Stacking
method✓ Weldingposition✓ Heat input for
welding✓ Welding gap

Element test
✓ Welding gap(Equipment similar
to the actual facility)

Implemented

Full scale mock-up tests✓ Series of procedures✓ Process management✓ Inspection(Fluorescent PT)✓ Verification of weldingstrain✓ Cold crack measures©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.158② PCV connection sleeve installation and welding by remote operation[Issues]• Considering the on-site workability and quality of welding, the gap between the PCV and the sleeve has to be
reduced as much as possible. Accurately installing the PCV connection sleeve by remote operation is a challenge,
based on the work environment (radiation dose, etc.).
• Also, establishing the method of remote welding considering the remote installation accuracy (gap) is a challenge.
[Implementation details]•
The pre-conditions related to the study are consolidated.
•
The requirements for installation of the sleeve, etc. connected to the PCV byremote operation are organized, and the method of installation by remote
operation, the equipment and devices, and procedures are studied.
(The connection method considering the possibility of the PCV side being
deformed, the acceptable maximum load on the R/B floor, etc. are considered.)••

The requirements for welding, repairing, inspecting and maintaining the sleeve
are consolidated, and the method of implementing a series of operations such as
welding procedures, inspection and maintenance by remote operation, including
the development of methods considering accuracy of installation by remote
operation, remote welding equipment and required tools, pre-processing such aspolishing before welding, are studied.
Element tests on the remote sleeve installation method and the welding
procedures are planned and implemented to verify feasibility.

Illustration of the PCV connection sleeveremote installation (Unit 3)
Robot
Scaffolding seal
cover installationequipment[Expected outcome]•
Presentation of a method for remotely installing the sleeve.
•
Presentation of a series of remote welding procedures and remote maintenancemethods related to the sleeve.
Polishing and inspection equipment
among other equipment

Illustration of PCV connection sleeve welding equipment©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.159② PCV connection sleeve installation and welding by remote operation[Outline of procedures while using the actual facility (1/2)]
1. Before installing the access tunnel

2. Shielding door installation

3. Removal of R/B wall and interfering
objects

4. BSW opening (Block-out)

Simple house
RemovalTemporary shield(Remotely operated)

Shielding door

5. Temporary shield installation

6. PCV connection sleeve installation

PCV connection sleeve

Removal of interfering objects such as
RHR, etc.

Simple house (Prevention of dust
dispersion)

7. Access tunnel Installation

8. Equipment hatch opening

Access tunnel
Equipment hatch opening

Additional building

Temporary shield
Measures against dose from inside the
PCVArea for additional shield installation(Refer to the following page for detailed
explanation)

Installation of additional shielding as
required©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.160② PCV connection sleeve installation and welding by remote operation[Outline of procedures while using the actual facility (2/2)]
6. PCV connection sleeve installation
6.1 Surface processing and opening investigation (3Dscanning etc.) → Reflection of shape into the PCV
connection sleeve

6.2 Installation of remote installation equipment

6.3 Installation of PCV connection sleeve

Delivery equipment

Surface processing equipment
and 3D scanning

Temporary receiving stand6. PCV connection sleeve installation

6.4 Fixing of PCV connection sleeve

6.5 Carrying-in of the scaffolding removal equipment/ Removal of scaffolding

6.6 Carrying-in of the welding equipment / Welding /Inspection
Tool box

Manipulator
AT sleeve

Rack for the tool changer(Various types of work heads)

Rack for the tool change(various types of work heads)

Box for collecting cut pieces
Cutting head

Tool for transporting the cut pieces

Scaffolding seal cover
SliderManipulator for work

Remote-controlled robot©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.161② PCV connection sleeve installation and welding by remote operation: (a) Remote installation
Table of Contents(a) Installation by remote operation⚫ Requirements⚫ Selection of remote installation equipment⚫ Full view, motion axis, overview of installation steps⚫ Installation procedure⚫ Simulation scope⚫ Mock-up equipment structure⚫ Comparison with actual facility⚫ Test plan, test flow
⚫ Measurement correlation diagram⚫ Test results, issues(b) Welding⚫ Test plan, test results
1) Welding2) Abrasion test3) Fluorescent PT test4) Dimension measurement
5) Cold crack test
⚫ Summary of test results©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.162② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Requirement (Consolidation of preconditions)]
No

Items

Pre-conditions

Remarks

1

TargetUnit 1: Installed from the northern side
Unit 2: Installed from the southern side
Unit 3: Installed from the southern side

Installed from the same opening as
the access tunnel main body in all
units

2

Permissible load on the
R/B floor

Approx. 4.9 ton/m2

The permissible load on the floor
after making the BSW opening andthe R/B wall opening is 750ton/m 2.

3

4

Unit 1: W5060×H6000mm
Unit 2: W6300×H6100mm
Unit 3: W6100×H6100mm

Dimensions of theassumed R/B opening

Distance from the R/B wall
to the equipment hatchA
BSW opening (front view)

Cross-section A-A

Unit 1: Approx. 16m
Unit 2: Approx. 18m
Unit 3: Approx. 18m

Interfering objects insideand outside the Reactor
Building

All must be removed.

6

BSW opening (floor
surface)Must be flat and at the same level as thefirst floor

7

Equipment hatch shell

Rust, etc. must be removed.

5

A

PCV connection
sleeve weight
Unit 1: Approx. 25ton
Unit 2: Approx. 40ton
Unit 3: Approx. 40ton

PCV side

H3000
Required accuracy
The gap between the PCV connection sleeve
and the equipment hatch shell is 7.5 mm orless (Target value)

Remarks
During the FY2019-20 Subsidy Project it was confirmedthat a gap of 20mm or less can be welded, but
considering the on-site workability, as it is desirable tohave a gap of 7.5mm or less, the target value is set at
7.5mm.

Note: The contents of this slide are cited from the results of the studies on the PCV connection sleeve remote
installation equipment concept outsourced to TEPCO HD (Implemented in FY2020-21).

W3830
Access tunnel side

D2230

Bird's eye view of the PCV connection
diagram (Unit 1)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.163② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Selection of remote installation equipment]
Proposal 3 and 4 are rated as “✓”. Since proposal 3 is delivered using the same delivery method as access tunnel main body, italready has a proven track record. Also, since the same equipment is used, it is superior over other proposals in terms of the schedule
as well. → Proposal 3 indicated by the red frame in the table below is selected.
(Proposal 1) Forklift method(Proposal 2) Traveling rail method

Permissible load on building
floor(Unit 3: 4.9tm2)△(Needs to be analyzed)

x(Tip foot part load capacity x)

Equipment scale

Small

Large

Large

Large

MediumExcavation outside the R/B

AbsentSmall scale (or absent)

Present

Present

Small scale (or absent)

Track record

Present

AbsentPresent(Access tunnel main body mock-up)

AbsentRegular machine elements

Absent(Track record of retracting of boom ispresent)

x

x

✓

✓

△

(Manufacturing) Possible.
(Method) Possible. Load bearing points
need to be studied.

(Manufacturing) Possible.
(Method) Unknown. Viability of the air
casters needs to be verified, andmeasures to prevent spread ofcontamination due to wind pressure are
required.

Feasibility(Manufacturing) Possible.
(Method) Since there is momentum at
the tip, it is difficult to reduce the size,
and interference cannot be avoided.

(Manufacturing) Although complex, it ispossible.
(Method) It is difficult to reduce the loadon the floor when inserted through the
opening, and hence the floor load
capacity cannot be met.

(Proposal 3) Integrated delivery method(Proposal 4) Rail delivery method✓(As it is cantilevered it does not come in contact with the floor surface)(Manufacturing) Possible.
(Method) Possible. Mock-up of thedelivery has been implemented. The
preceding and subsequent processes
need to be considered.

(Proposal 5) Boom method△
Load from an air caster

Grave issues

Present (Interference with the pillars)

Present (Load capacity)

AbsentAbsentPresent (Continuous air supply in theevent of an emergency)

Applicability to other unitsx(Interference with the pillars)✓(Except building floor load capacity)✓✓✓(Except building floor load capacity)

Impact on schedule

Minor

Major

Medium

Major

Minor

Evaluation

x

x

✓

✓

x

©International Research Institute for Nuclear Decommissioning

Note: The contents of this slide are cited from the results of the studies on the PCV connection sleeve remote installation equipment concept outsourced to TEPCO HD (Implemented in FY2020-21).

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.164② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Conceptual design_full view (Proposal 3)]Note) The figure illustrates Unit 3

Counter weight (CW)

Main frame

PCV connection sleeve
Equipment at the tip

Delivery equipment

50 (Jack-up at the time of delivery)

Note: The contents of this slide are cited from the results of the studies on the PCV connection sleeve remote©International Research Institute for Nuclear Decommissioning
installation equipment concept outsourced to TEPCO HD (Implemented in FY2020-21).

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.165② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Operation axis]

Delivery unit
(Jack / minimum 4 units)

Oscillation
Rotation
Extension

PCV equipment
sleeveRotating unit

Extension unit
Hoisting unit
Oscillating unit

Illustration of equipment at the tip

Unit

Composition

Use applications

DeliveryXYZ Jack: 4 units(Can be operated on asingle shaft)

Positioning up to the front of the BSW opening

Rotation

Rotation motor: 1 unit

Positioning up to the front of the BSW opening

Extension

Extension motor: 1 unit

Insertion into the BSW opening / Final fine adjustments

Oscillation

Rotation motor: 1 unit

Final fine adjustments (Aligning the surface with theequipment hatch end face

Hoisting

Hoisting motor: 4 units(Stand-alone operationof the 4 units is possible)

Final fine adjustments, seating / deflection
compensation (leveling)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.166② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Conceptual design_outline of installation steps]⚫ Advanced preparations and equipment installation are tasks carried out directly by humans (not remote
operations). Delivery is a remote operation.
⚫ The auxiliary lines and other markings play an ancillary role in delivery. Final verification is carried out using
camera or measuring instruments.
Step

Items

Overview

Work

1

Advanced
preparations

The required auxiliary lines or markings are done before installing the delivery
equipment.

Not a remote
operation

2

Equipment
installation

The delivery equipment is installed including ground improvement.

Not a remote
operation

3

Delivery (1)The sleeve is delivered up to right in front of the BSW opening.

Remoteoperation

4

Delivery (2)It is delivered up to right in front of the equipment hatch shell by means of theequipment at the tip, and fine adjustments are made while confirming the gaps in theentire periphery by means of a camera, etc.

Remoteoperation

5

Positioning

It is seated on the BSW floor surface using the hoisting unit.

Remoteoperation

6

FixingReaction force jack (Fixing jack) is operated to fix it on to the BSW.

Remoteoperation

7

Withdrawal

The delivery equipment is withdrawn.

Remoteoperation

Note: The contents of this slide are cited from the results of the studies on the PCV connection sleeve remote installation equipment concept©International Research Institute for Nuclear Decommissioning
outsourced to TEPCO HD (Implemented in FY2020-21).

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.167② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Installation procedure: (1/2)]
1. Delivery equipment / PCV connection sleeve
installation

2. Main boom / CW1 installation

Deliveryequipment

Delivery equipment /Equipment at the tip

Measurement
A# Including excavation before installing thedelivery equipment
4. 4m forward movement of main boom

3. 3m forward movement of main boom / holdingof the PCV connection sleeve

5. Connection of CW2

6. Completion of CW installation

Deliveryequipment

Connection of CW3, 4 just like CW2©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.168② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Installation procedure: (2/2)]
7. 2.4m forward movement of main boom

8. 45° rotation

Equipment at
the tip

Deliveryequipment

9. Forward movement of main boom

Deliveryequipment

Measurement B
10. PCV connection sleeve positioning / insertion/ seating

Equipmentat the tip

11. Withdrawal of boom (extension unit)

Equipment at
the tip

12. Forward movement of main boom

Deliveryequipment

Measurement
C, D, E

©International Research Institute for Nuclear DecommissioningNo.169

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Approach towards installation]
The content in red frame indicates the approach towards the present method (Remote installation of PCV connection sleeve)
If the target can be verified directly

If the target cannot be verified directly

Object to be installed(Closer)
Target 1

Object to beinstalled

Object to beinstalled

Object to beinstalled

Target 1

T1

T1

T1

Target 1
Aligning
accurately

TemporarytargetAligning
accurately# When the target and object to be installed are near

# When the target and object to be installed are far

If the target can be verified directly, positioning is carriedout while directly verifying the target.

If the target can be directly verified but is far, a
temporary target is set up, and until the target getscloser, positioning is carried out roughly using the
temporary target as the guide. After getting closer to thetarget, positioning is carried out while directly verifying
the target.

(The following is carried out in the above case)① Positioning of the object to be installed while directly
verifying Target 1.

Target 2

Aligningroughly(Outline of procedures)① Setting up the temporary target.
② Roughly aligning the object to be installed withrespect to the temporary target③ Positioning the object to be installed while directly
verifying Target 1, after getting closer to Target 1

Aligning
accurately

Moving the target
to another location
Blind

If the target cannot be directly verified or if theverification is difficult, the target is moved to anotherlocation, positioning is carried out considering the target
after relocation as the correct target.
(Outline of procedures)① Moving Target 1 to another location, and considering
Target 2 as the correct target②Positioning the object to be installed with respect toTarget 2(Note)
・Since Target 2 is considered as the correct target,
positioning needs to be correctly carried out with respect
to Target 2.
・Accuracy of moving the target to another location isneeded as well.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.170② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Scope of simulation]
The portion indicated by the red frame is simulated, and a verification test is conducted.
CW3

CW2
Main boom

CW4

CW1

PCV connection
sleeveRed frame: Scope of simulation
Temporaryreceiving stand
Deliveryunit
Equipmentat the tip

Illustration of entire actual facility (Before delivery)
Rotating unit

Extension unit
Hoisting unit
Oscillating unit

Illustration of equipment at the tip©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.171② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Structure of the mock-up equipment]

Direction in which
the beam can move(rotation)

Center of gravity(When the slide beam is extended)

Direction in which the
hoisting and rotating
part at the tip can move(rotation)

Center of gravity(When the slide beam is retracted)

Direction in which the slide
beam can move (longitudinal)

3D measurement
equipment
Direction in which the hoisting
and rotating part at the tip canmove (vertical)

Center of gravity(when the slide beam is extended)

Center of gravity(when the slide beam isretracted)

Simulated PCV connection sleeve (Fordetails, refer to 21-AD1001)

Measuring arm(For details, refer to
21-AD3001)

PCV connection sleeve

Component 105: The entire equipment is tilted using a height adjustment
mechanism in order to simulate maximum deflection.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.172② PCV connection sleeve installation and welding by remote operation[Comparison with actual facility] Remote installation equipment specifications (1/2)
No.

0

Items

Entireequipment

Composition ofoperation axis

Composition12

3

Deliveryunit

Rotating unit
(Equipment at
the tip)

Extension unit
(Equipment at
the tip)

Actual facility (assumed)

Mock-up

Delivery unit: 3 axes (X, Y, Z)

Not simulated(Substituted by moving the simulated opening)

Equipment at the tip: 7 axes (Rotation, retraction,
oscillation, hoisting x 4)

Same as on the left

Hydraulic jacks × 4 units

Installation
accuracy(Resolution)

20mm or lessComposition

Power cylinder

Scope ofmovement

0 to 45° (Maximum 50°)

Speed

Rated: 0.03 rpm (Approx. 4.2min @ 45° Rotation)
Maximum: 0.05 rpm (Approx. 2.5min @ 45°
Rotation)

Resolution

0.0014°/ rev(1.5mm/rev @ PCV connection sleeve tip)

Composition

Power cylinder

Scope ofmovement

0 to 1900 mm (+10mm/-100mm)

Speed

Rated: 0.24 m/min (4.0 mm/s)
Maximum: 0.60 m/min (10.0 mm/s)

Resolution

0.4 mm/rev

Not simulated(Substituted by moving the simulated opening)

Same as on the left

Same as on the left

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.173② PCV connection sleeve installation and welding by remote operation[Comparison with actual facility] Remote installation equipment specifications (2/2)
No.

4

5

Items

Oscillation
unit(Equipment at
the tip)

Hoisting unit
(Equipment at
the tip)

Actual facility (assumed)
Composition

Power cylinder

Scope ofmovement± 5° (Maximum 31.5°)

Speed

Rated: 0.03 rpm (Approx. 28sec @ 5° Rotation)
Maximum: 0.05 rpm (Approx. 17sec @ 5°
Rotation)

Resolution

0.025°/rev(0.75mm/rev @ PCV connection sleeve tip)

Composition

Servo motor + trapezoidal screw

Scope ofmovement

Maximum St.500mm

Speed

Rated: 0.06 m/min (1.0 mm/s)
Maximum: 0.075 m/min (1.25 mm/s)

Resolution

0.025 mm/rev

Capacity

20 ton/unit

Mock-upSame as on the left

Same as on the left

Remarks⚫ An encoder (26bit) is used for detecting the position of each unit of the equipment at the tip.
⚫ The optimum speed is confirmed through tests.
⚫ The end point of the movement is detected using a limit switch.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.174② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Comparison with actual facility] PCV connection sleeve
Items

Actual facility (assumed)

Mock-upSpecifications

Target equipment: 1F-3
External dimensions: W3730×L2812×H3025(mm)
Weight: Approx. 40 ton

Target equipment: 1F-3
External dimensions: W3730 x L2812 x
H2785(mm)Weight: Approx. 12 ton

PCV side

PCV side

Image

Access tunnel side

Remarks

Inside BSW

Access tunnel side

Inside BSW

Height: Not simulated as there is no interference on the outer side of the BSW (When installation iscomplete / portion indicated by dotted line), and there is no impact on ease of installation. The actual
facility external dimensions were simulated for the dimensions inside the BSW.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.175② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Comparison with actual facility] BSW opening / Equipment hatch
Items

Specifications

Actual facility (assumed)
Target equipment: 1F-3
・BSW opening
Internal dimensions (narrower side): W3310 x D998 x
H2785(mm)Internal dimensions (broader side): W3510 x D800 x
H2885(mm)・Equipment hatch
Shell: φ3050 x t70mm

Mock-upTarget equipment: 1F-3
・BSW opening
Internal dimensions (narrower side): W3310 x D998 x
H2785(mm)Internal dimensions (broader side): W3510 x D800 x
H2885(mm)・Equipment hatch
Shell: φ3050 x t70mm

Image

Remarks―©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.176② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Comparison with actual facility] Operation axis and rough outline of the steps involved

Delivery unit
(Jack / minimum 4 units)

Oscillation
Rotation
Extension

Actual facility(assumed)
Mock-up
Simulated opening(Before moving)

Simulated opening(After moving)

Simulated delivery(Manual)Oscillation

Rotation

Extension

Proce
dure

Outline of procedures while
using the actual facility

Outline of procedures while
using mock-up― (Not simulated)

1

Delivery (Approx. 10m)

2

40° rotation

Same as on the left

3

Delivery (Approx. 2.8m)

Simulated delivery (Approx. 2.8m)

4Delivery (Approx.
0.7M/Measurement value) +Rotation (Approx.
5°/Measurement value)

Simulated delivery (Approx.
0.7m/Measurement value) +Rotation (Approx.
5°/Measurement value)

5

Extension (Approx. 1.8m)

Same as on the left

6

Fine adjustments (Extension /Oscillation / Hoisting)Same as on the left

7

Seating (hoisting)Same as on the left

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.177② PCV connection sleeve installation and welding by means of remote operation: (a) Remote installation[Test plan (1/2)]
Items to be verified

Implementation details

Items to be monitored,measured and recorded

Criteria

Verification through studies and tests
Verification of visibility ofcameras, etc.

The installation location and visibility of the cameras at eachstep are studied and verified.

➢ Camera image➢ Remote work should bepossible based on theimages from the camera.

Verification of detailed
procedures

The installation procedures are studied in detail, the criteria
for moving on to the subsequent step are compiled andverified by tests.

➢ Equipment operation data

➢ Remote work should bepossible by following theprocedures studied.
➢ The criteria should be met at
every hold point (Refer to thefollowing page).

Installation accuracy

Installation accuracy is verified using a simulated PCV
connection sleeve.

➢ Installation accuracy➢ 20mm or less(Target: 7.5mm or less)

Verification through studies

Verification of object to beinstalled

The method of verifying the current status of the equipment
hatch shell and BSW, and the method of reflecting the shapeafter verification are studied.

Verification of final gap

The method of verifying the final gap is studied.
① Verifying that the gap is 20mm or less (target: 7.5mm orless)② Estimating the gap

Method of detecting seating

The method of detecting that the PCV connection sleeve has
been seated on the BSW is studied, and verified.

Verification of the fixing
methodThe procedures for fixing the PCV connection sleeve on to the
BSW are studied in detail－©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.178② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Test plan (2/2)] Criteria for moving on to the subsequent steps
Items

Before making the BSW opening

Final location

Equipment
hatch shell

Equipment
hatch shell
PCV shell

PCV shell

R/B wallR/B wallHold point (HP)

Equipment hatch shell

PCV connection
sleeve center
Equipment hatch shell

Direction of delivery

Misalignment
Measurement

Direction of delivery

Gap
PCV connection sleeve
BSW opening center

Angle
Criteria

Misalignment: 20mm or less
The angle between the BSW opening and the PCV connection
sleeve surface: 1° or less

Gap: 20mm or less (target ±7.5mm or less)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.179② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Test flow]
Measurement
A

Verification of the measurement arm and sleeve
position(Actual facility) Delivery inside
the R/B

40° rotation

Planned (design): 40°

Moving the
opening

Planned (design): 2300mm, 2800mm
Verification item: Camera image

Measurement
B1

Calculation of movement up to the position before
insertion into the BSW opening

Rotation(Measurement
value)The value of Measurement B is entered (Design
value: 5°)

Moving the
opening(Measurement
value)The value of Measurement B is entered (Design
value: 700mm)

Yes

Fine
adjustment

Misalignment: ±20mm or lessNo

Measurement C is carried out when the amount ofextension is 500, 1000, and 1500
Verification items: Misalignment (±20mm or less)

Yes
Adjustment #Measurement
D# Adjustment is made by bringing
back the PCV connection sleeve up
to the front of the BSW opening(extension 0mm).

The distance from the end face of the equipment
hatch shell up to 20mm is calculated.

Insertion 2

The sleeve is inserted up to the remaining (gap) 20mm
while checking the distance with the wall at every
100mm.

Measurement
E

The gap is measured and the distance covered up to
the final position is calculated.

Insertion 3 /Oscillation

Operation is carried out based on results of
Measurement E.
No

Measurement
E

No
Measurement B2,
C1(Misalignment,
etc.)

Insertion 1 +Measurement
C1, C2

It is confirmed that the gap is 7.5mm or lower.

Yes
Seating /FixingCarrying out seating / fixing (including verificationof gap)©International Research Institute for Nuclear DecommissioningNo.180

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Measurement correlation diagram]Note) Since the measurement arm base moves, it is equivalent to what is called as thetool coordinate system in robotics.
Relative
position
PCV connection sleevereference point

Relative
position

Tip equipment
reference point

Relative
position

Calculation A

PCV connection sleevewall / floor
Fixed
Drawings / actual
measurements

Measurement C
Relative
position

Distance

Measurement armbase coordinates
Measurement A

Calculation C(Measurement
criteria)

Calculation D, E

Calculation B
Measurement C

BSW
wall / floor
Equipment hatch shellreference point

Measurement D, E
Fixed

Measurement B

BSW
referencepoint
Fixing©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.181② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
Measurement A

The 3 end faces of the PCV connection sleeve are measured, and the relative position of themeasurement arm base coordinates and the PCV connection sleeve reference point is verified.
The center position is verified by measuring points A and B, and the reference plane(reference point) is created by measuring any point C.

PCV connection sleeve
PCV connection sleevereference point

Point C

Equipment at the tip
Point A

Point B
PCV connection
sleevehorizontal center

Measurement armbase coordinates

Welding plate©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.182② PCV connection sleeve installation and welding by means of remote operation: (a) Remote installation[Explanation of the procedures]

40°
Rotation

PCV connection
sleeve40° rotation

BSW opening
Before rotation (0°)

Rotation (40°)

Moving the
openingMovingMoving the opening (2300mm)

MovingMoving the opening (2800mm)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.183② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]

Measurement
B1

The 3 end faces of the BSW opening are measured, and the angle of rotation and the delivery distance iscalculated. The approximate center position is verified by measuring points A and B, and the reference plane(reference point) is created by measuring any point C.

BSW opening (lateral view)

BSW opening (front view)

PCV connection sleeve
Point C
Equipment at the tip
Point A

Point B
Center of thefront of the BSW
opening part

Tip equipment
reference point
PCV connection sleeve
Measurement arm

Laser
BSW opening©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.184② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
Rotation

Rotated according to the measurement value
using the rotating unit.

Moving the
opening

The opening is moved according to themeasurement value (delivery)

Calculation of the 2 angles formed
Calculated value = Angle of rotation
Center of the opening
Opening guideline (X)Obtained by measurement

Obtained bymeasurement

PCV connection sleevereference point

Tip equipment
guideline (X)

BSW

RotationP2

PCV connection sleevereference point
Delivery center
PCV connection sleeve

Delivery center40°

Rotation center

Distance between P1 and P2 iscalculated.
Calculated value = Delivery distance

P1
Delivery

P1: Point of intersection of the delivery center and the center ofthe opening
P2: Point of intersection of the delivery center and PCV
connection sleeve reference point©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.185② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
Measurement B2

The level difference of the BSW opening is measured, and the distance between the PCV connection
sleeve and the equipment hatch shell is calculated. It is confirmed that the result of calculation islower than the stroke (1900mm) of the extension unit.

Extent ofinsertion
The distance up to the equipment hatch shellis calculated based on the measurement
result.

Equipment hatch shell

Measurement

The distance from the PCV connection
sleeve to the level difference of the
BSW opening is measured.

BSW opening
Level difference

Tip equipment
guideline (X)PCV connection sleevereference point

Delivery center©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.186② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
The distance between the BSW opening wall surfaces (1 location on each side / Total 2 locations) and thePCV connection sleeve wall surfaces (1 location on each side / Total 2 locations) is measured, and it isconfirmed that the misalignment is below the permissible value of ±20mm. If misalignment exceeds thepermissible value, adjustments are made by “Rotation” and “Delivery (Moving the opening)”

BSW opening (lateral view)

Equipment hatch door

BSW opening (front view)

Connecting portion (endface of cylinder)

Measurement
C1

Equipment at the tip

Measurementarm basecoordinates(Note)・ Implemented at an extension stroke of 500mm pitch
・ The minimum gap between the inner surface of the BSW and the outer surface of the PCV connection sleeve is 45mm on one side.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.187② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
The distance between the BSW opening floor surface (1 location) and the PCV connection sleeve floor
surface (1 location) is measured and the height from the BSW opening floor surface is verified.

BSW opening (front view)

Equipment hatch door

BSW opening (lateral view)

Connecting portion (endface of cylinder)

Measurement C2

Equipment at the tip

Measurementarm basecoordinates

Note) Implemented at an extension stroke of 500mm pitch©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.188② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
Insertion 1

The PCV connection sleeve is inserted while confirming the gap between the BSW wall and the PCV
connection sleeve with a camera.

Position of the camera

Before insertion (Extension stroke: 0mm)

BSW
opening

Insertion (Extension stroke: 500mm)

Insertion (Extension stroke: 1500mm)

PCV connection
sleeve side

Insertion (Extension stroke: 500mm) / Image from rear camera /left side

Insertion (Extension stroke: 500mm) / Image from rear camera /right side
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.189② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
Measurement
D

The distance up to the end face of the equipment hatch shell is measured at the position where theextension stroke is 1500mm, and the extent of movement up to the position approx 20mm in front of
the equipment hatch shell is calculated.
Equipment hatch shell
Equipment hatch shell

Equipment at the tip

Equipment hatch shellreference point

PCV connection sleevereference point©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.190② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
Insertion 2

After inserting up to 1800mm, the PCV connection sleeve is inserted approx. 20mm in front while checking theposition of the equipment hatch shell and the PCV connection sleeve with the camera of the 3D measurement
equipment.

Equipment hatch shell(Inner surface of
cylindrical part)

Insertion (Extension stroke:
1600mm)Laser

PCV connection
sleeve end face

Insertion (Extension stroke:
1800mm)Gap

PCV connection sleeveend face (t=12mm)

Insertion (Extension stroke:
1850mm)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.191② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures] Position up to approx. 20mm until the final target

Measurement
E

The gap between the equipment hatch shell end face and the PCV connection sleeve is measured at 7
points (0°, ±30°, ±60°, ±120°), the final extent of movement is calculated.

Equipment hatch shell
Equipment hatch shell
0°
-30°

30°

-60°

60°

-120°

120°

Equipment hatch shellreference point

Equipment at the tip

PCV connection sleevereference point©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.192② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures] Position up to approx. 20mm until the final target

Measurement
E

The gap between the equipment hatch shell end face and the PCV connection sleeve ismeasured at 7 points (0°, ±30°, ±60°, ±120°), the final extent of movement is calculated.

3D measurement
equipment

Laser
Laser
Measurementarm

Equipment
hatch shell
PCV connection
sleeveEquipment
hatch shell

Measurement position -120°

PCV connection
sleeveMeasurement position 120°

©International Research Institute for Nuclear DecommissioningNo.193

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures] Position up to approx. 20mm until the final target
Measurement
E

The gap between the equipment hatch shell end face and the PCV connection sleeve is measured at 7
points (0°, ±30°, ±60°, ±120°), the final extent of movement is calculated.

Laser
Gap

Equipment
hatch shell
PCV connection
sleeveMeasurement position 120°
(Digital camera image)Measurement position 120°
(3D measurement camera
image)

Point cloud data
Point cloud data
(Same angle as the image) (For verifying the gap)

©International Research Institute for Nuclear DecommissioningNo.194

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Explanation of the procedures]
Insertion 3 /Oscillation

The equipment is operated in the order of hoisting, oscillation and extension based on the results of
Measurement E, and is moved to its final position. The stopping distance from the equipment hatch
end face is established.

Final positioning

Results of
Measurement E

Measurement
point (°)

Average Minimum Maximum
value
value
value

Gap
measurement
Times Measurement

Reset

point (°)

Average(mm)

Minimum(mm)

Measurement
frequency

Maximum(mm)

Average

Deviation from the equipment hatch shellreference point and the PCV connection
sleeve reference point

Minimum
Maximum

DeleteRadiusCircle parameter
calculation
Control input
calculation

Left front(D)Right front(A)Slide

Stopping distance

Left rear(C)Right rear(B)Oscillation

The extent of movement up to
the final position is calculated.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.195② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Selection of test conditions ①]
The clearance with the PCV connection sleeve remote installation equipment and the R/B opening part is approx. 600mm on one
side. If the insertion angle deviates by ±2°, it gives rise to a deviation of approx. 500mm in the vicinity of the R/B opening. Hence tests
for verifying whether measurement and calculation is possible if there is a deviation of ±2°were conducted.
Further, since the mock-up equipment cannot be moved, tests were conducted keeping the angle of the rotating unit at 40°±2° during
Measurement B.

Approx. 500mm

Delivery unit
(Jack / minimum 4 units)

-2°
+2°

Approx. 500mm©International Research Institute for Nuclear DecommissioningNo.196

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Selection of test conditions ①]
BSW opening center

BSW opening center

BSW

BSW

Tip equipment
center (X)Final delivery position(+2°)

Tip equipment center (X)Rotation center

700(mm)Delivery center (+2°)

40°
A straight line at 45° from the BSW opening
A straight line at 45° from the BSW
opening center = Delivery center
Final delivery position(Rotation center)

⚫
⚫
⚫
⚫

40°

Delivery center (-2°)

700
(mm)

Measurement B
implementation location(Rotation center)

Final delivery position(-2°)

Measurement B
implementation location(Rotation center)

The point of intersection of the “BSW opening center” and “the straight line at 45° from the BSW opening center becomes the final delivery positionat the rotation center in the drawing.
The position that is 700mm in front (outside R/B) of the above mentioned rotation center becomes the position for carrying out Measurement B.
Considering the range of movement of the measurement arm and the range in which measurement is possible (measurement range), as long as
the rotation center is in the 100mm diameter of the position for carrying out Measurement B, Measurement B is possible. Adjustment can be madewith the help of the delivery unit (accuracy ±20mm). The measurement position is marked beforehand as required, and is verified with a camera.
It was confirmed that since the rotation angle is mechanically set at 40° during measurement, even if the “straight line at 45° from the BSW opening
center” and “delivery center” shift, measurement (calculation) is possible.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.197② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Selection of test conditions ②]
The delivery distance is calculated based on Measurement B, and the opening is moved using the delivery equipment.
Since the accuracy of the delivery equipment is ±20mm, the test on moving the simulated opening is conducted for thedelivery distance calculated based on Measurement B ±20mm.

PCV connection sleevereference point-20mm

Center of the opening

P2

Obtained by measurement+20mm
Delivery center
P1
Distance between P1 and P2 iscalculated.
Calculated value = Delivery distance

Delivery
P1: Point of intersection of the delivery center andthe center of the opening
P2: Point of intersection of the delivery center and
PCV connection sleeve reference point©International Research Institute for Nuclear DecommissioningNo.198

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Test results]⚫ The results under all conditions satisfied a “gap of 7.5mm or less” which is the required specification.
⚫ The error in the calculated measurement and actual measurement was approx. ±2mm or less. The error in thecalculated measurement value and the actual measured value was 2mm or more at 120° in Test number 2, 5. Referto the following page for the reasons.

Measurement
C1(Misalignment)

Measurement B
No.

Testing conditions

ActualInitialdeliveryrotation
ActualAngle of Delivery distance Measur(°)
measurrotation distance (mm) ement
0°
ement
(°)
(mm)
(mm)
(mm)

Measurement E (Final)(mm)

Actual measurement (Final)(mm)

30° 60° 120° -30° -60° -120° 0°30° 60° 120° -30° -60° -120°

1

No error

40

44.8

683.1

684

0.1

0.5

2.4

2

0.4

4.1

2.7

3.9

4.6

3

3

2

4

2

3

3

2

Angle misalignment - 2°

38

44.6

671.1

672

-2.3

-2

2.4

1.8

1.9

0.4

1.5

2.5

3.1

2

3

3

6

1

1

2

3

Angle misalignment + 2°

42

44.6

662.2

662

-1.5

-3

2.5

2.1

2

4.7

2.1

-

3.5

3

3

3

6

2

1

2

4

Delivery error +20mm

40

44.8

684.6

705

18

20

4.8

3.9

3

5

4.6

4.4

4.7

4

4

4

6

4

4

4

5

Delivery error -20mm

40

44.8

675

655

-20.2

-20

2

1.1

0.7

0.8

2.6

4.4

3.2

2

1

0

3

2

3

2

Note: Results of measurement before seating(before making the opening)©International Research Institute for Nuclear DecommissioningNo.199

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve installation and welding by remote operation: (a) Remote installation[Issues] Measurement precision

Measurement E is carried out by obtaining point cloud data by means of the light section method and measuring thegap. It is desirable for the laser to be perpendicular to the gap. However, at the ±120° position, the laser becomes almost
parallel to the gap. Hence it becomes difficult to obtain the point cloud data. As a result, there are cases in which accuracy
is poor. This phenomenon can be addressed by increasing the number of shafts of the measurement arm (positioning
equipment of the 3D measurement equipment) to 6 shafts from the current 5 shafts. Studies will be conducted on such an
addition in the actual facility in accordance with the required specifications.

Measurement position 0°
PCV connection sleeve

3D measurement equipment

Equipment hatch shell
Laser

Gap

Gap

PCV connection sleeve

Equipment hatch shell
PCV connection sleeve

Laser

Equipment hatch shell

Good example:
Measurement position 0°

Measurement position 120°

Photo from the PCV side

Measurement position 120°
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.200② PCV connection sleeve remote installation and welding: (b) Welding
Table of Contents(a) Installation by remote operation⚫ Requirements⚫ Selection of remote installation equipment⚫ Full view, motion axis, overview of installation steps⚫ Installation procedure⚫ Simulation scope⚫ Mock-up equipment structure⚫ Comparison with actual facility⚫ Test plan, test flow
⚫ Measurement correlation diagram⚫ Test results, issues(b) Welding⚫ Test plan, test results
1) Welding test
2) Abrasion test3) Fluorescent PT test4) Dimension measurement
5) Cold crack test
⚫ Summary of test results©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.201② PCV connection sleeve remote installation and welding: (b) Welding[Results up to FY2020]
It was verified during the element tests conducted in FY2019-20 that a gap of 20mm or less can be welded. In addition,issues were identified considering remote operation as well.
Issue ① Joining defects

Issue ② Formation of oxides

From the results oftests conducted aspart of the FY20192020 subsidy projects

From the results oftests conducted aspart of the FY20192020 subsidy projects
Example ofjoining defects

OxidesIssue ③ Concerns about cold cracks

Issue ④ Need for remote inspection method

From the results oftests conducted aspart of the FY20192020 subsidy
projects

Hot crack
Cold crack
Welding of thick plates(Concerns about cold cracks)

Fluorescent
PT

These issues were studied and full-scale simulated tests wereconducted to verify remote operability.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.202② PCV connection sleeve remote installation and welding: (b) Welding[Results up to FY2020]
No.

Source studied and verified(Issues identified during the
FY2019-2020 subsidy projects)

Study/verification items

Overview of studies①

Joining defects

Specification of process management

The actual work will be carried out remotely, and the camera visibility will belimited. Hence torch positioning, angle, etc. need to be verified by means of amock-up. What exactly needs to be verified needs to be specified.

②

Formation of oxides

Study of small welding head
(Improving shielding capabilities)

Formation of oxides was not observed in tests conducted by setting
conditions. The formation of oxides needs to be controlled and the frequencyof polishing needs to be reduced as much as possible by optimizing the gas
nozzle.

③－１Concerns about cold cracks

Study of tests on cold cracks

Methods of verifying prevention of cold cracks when there is no pre-heating
and welding methods will be studied by conducting tests (T shaped coupling,etc.).

③－２

Concerns about cold cracks

Method of pre-heating

The method of pr-heating the equipment hatch (partial or full) will be studied.
(Not applicable if ③-1 can be implemented.)④

Need for remote inspection
methodStudy of inspection method other thanFluorescent PT

Methods for remote inspection will continue to be studied.

⑤

Vertical downward welding(Items that are not issues but need
to be studied in response to test
results)

Details of welding procedures, etc.
(Order of tack welding or welding)In the FY2019-20 subsidy projects, welding conditions up to a gap of 7.5mm
were considered verified since vertical downward welding can be substitutedby vertical upward welding. However, it is believed that the work efficiency isbetter in thecase of vertical downward welding depending on the welding procedures.
Firstly, the need for vertical downward welding will be clarified by studying theprocedures, etc.

⑥

Occurrence of false defects(Items that are not issues but need
to be studied in response to test
results)

Applicability of the selected abrasive
to actual environment

The applicability to actual environment needs to be studied and evaluatedbased on the data obtained during this subsidy project.

©International Research Institute for Nuclear DecommissioningNo.203

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding[Issues and items that need to be studied]

Step

1

2

3

4

Items

Advanced preparations

Welding

PolishingInspection

Study

Testing/Verification

Method of removing scaffolding considering post-processing (welding)－－

Study of rust removal equipment (blast)－#－

Study of scaffolding seal cover installation equipment－#－(1) Specification of process management✓✓(2) Improving shielding capabilities and downsizing✓✓(3) Study of pre-heating method and working method✓✓(4) Study of welding procedures (stacking procedures, etc. for irregular gaps)✓✓

Study on polishing machine and on the polishing guidelines✓✓(1) Study of fluorescent PT equipment and on inspection conditions (fluorescent agent
blast pressure, etc.)✓✓(2) Study of inspection method other than Fluorescent PT (including organizing therequired inspections)✓✓(3) Verification of the accuracy of dimension measurement (by means of the touch
sensor of a robot)✓✓

Issues and items that need to be studied

5

Repairs

Study of repairing equipment and method

－#

－

6

Pressure resistance test

Study of pressure resistance testing method (after connecting the access tunnel main
body)

－

－

Note) The items with “－” will be implemented during actual facility engineering# Studies conducted up to FY2020
Tests pertaining to welding, polishing and inspection indicated by the red frame in response to issues identified until FY2020,
will be designed and implemented in FY2021-22.
©International Research Institute for Nuclear DecommissioningNo.204

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding

A series of welding procedures are verified using a full scale simulated equipment hatch shell and power manipulator(robot).
Simulated PCV connection sleeve

Manipulator

Simulated equipment hatch

SliderReactor Building
floor level

Area ofoperation

Camera / lighting telescopic arm
Simulated scaffolding seal cover

Testing facility
Verification
contents

Items to be verified

Items to be monitored, measured and recorded

Criteria

Welding test・Establishment of uneven gap welding・Verification of welding deformation(strain)・Verification of remote work efficiency① Process management items such as welding
conditions, etc.
② Amount of welding deformation③ Results of non-destructive test (Dye PT, VT)✓ Welded portion should be in a sound state・Should pass the non-destructive test
・Required throat thickness should be secured

Abrasion test

・Verification of polishing work carried out
by means of remote operation① Selection of polishing tool
② Polishing guidelines✓ Polishing that does not hinder the fluorescent
PT should be possible

Fluorescent PT
test

・Verification of applicability to actual
facility① Blasting conditions of the penetrant② Surplus liquid washing conditions③ Identification of indication✓ It should be possible to detect the defect✓ Remote operation should be possible

Dimension
measurement

・Verification of guidelines for remotedimension measurement① Dimension measurement guidelines② Cross-sectional observation✓ Ascertaining of the accuracy of dimension
measurement©International Research Institute for Nuclear DecommissioningNo.205

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding
1) Welding test
Items to be verified

Items to be monitored, measured andrecorded・Establishment of uneven gap welding・Verification of welding deformation(strain)・Verification of remote work efficiency① Results of non-destructive test (Dye PT, VT)② Dimension measurement results (required
throat thickness)③ Amount of welding deformation④ Process management items such as welding
conditions, etc.

Criteria✓ Welded portion should be in a sound state・Should pass the non-destructive test
・Required throat thickness should be secured

・ During the remote MU test welding is carried out using the camera images.

Simulated PCV
connection sleeve(38t)Upper side: gap of
7.5mm

Simulatedequipment
hatch (90t)
Simulatedscaffolding seal
cover (12t)

Vertically uneven gap[Remote MU test piece][Combination test]
Test

Gap

Material

Objective

Combination test

Uniform gap of 7.5mm

SS400

Identification of remote work management items

Remote MU test

Vertically uneven gap of 7.5mm

SGV480/SM400B

Verification of a series of welding procedures©International Research Institute for Nuclear DecommissioningNo.206

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding
1) Welding test
① Establishment of uneven gap welding〇 Welding equipment
Welding material

Telescopic long shot camera(2 on both sides x 2)
Stroke: 1760mm

Manipulator (6 shafts)
Main body mass: 640kg
Transporting capability: 50kg
Tool changer

Tool changer
Bracket foradjusting the angle

Bracket foradjusting the angle

Shock sensor

TIG welding head

Slider from the backSlider from the front

SliderStroke: 3820mm
Maximum payload： 1200kg

TIG welding head

Orbima TIG500Ⅱ
AVC, OSC equipment

Long shot
cameraWelding
Robot power
supplyTIG welding headWith AVC, OSC mechanism

PolishingmachineControl equipment (robot, polishing machine, long shot
camera) & welding power supply

Remote control for the welding
operation©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.207② PCV connection sleeve remote installation and welding: (b) Welding
1) Welding test

① Establishment of uneven gap welding〇 Welding procedures
Block welding

Tack welding

1. Gap measurement
2. Tack welding of gaps that are 2mm or less
3. Welding is carried out by segmenting it in the circumferential
direction* *: Block welding(Underlaying fillet welding to bridge welding)
4. Welding between blocks (Underlaying fillet welding to bridge welding)(All-around seal welding completed)
5. Leg length welding （welding until the required [throat thickness(4.3mm)] is achieved)G≓7.5mm
PCV connection
sleeve(1) Underlaying fillet welding
Block welding
Welding between blocks

Equipment
hatch

Welding between blocks

Block welding
Welding
between blocks

Leg length welding

T**： Location where tack welding isplanned
B**: Location where block welding isplannedT is 15° pitch and B is 45° pitch〇 Block welding procedures
B3→B5→ B8→B4→B10→B11→B9→B6→B7→B2→B1〇 Procedures for welding between
blocksB4～B3→B10～B9→B11～B10→B2～B1→B4～B5→B6～B7→B7～B8→B11～B6→B1～B8→B9～B2(2) Bridge welding
Block welding
Welding between blocks(3) Leg length welding

Stacking where there are gaps

Segmented locations for underlaying fillet welding and bridge welding©International Research Institute for Nuclear DecommissioningNo.208

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding

1) Welding test
① Establishment of uneven gap welding〇 Welding conditions① TIG welding that results in comparatively good shaped beads is used as the welding method taking the non-destructive inspection into
consideration.
② Welding including tack welding is carried out under basic welding conditions③ The amount of deposition in between uneven gaps (change in gap) is adjusted by changing the amount of wire feed
④ Number of block welding passes are matched with the number of weld passes for the location where the gap is the largest. Even if thegap varies depending on the welding location (orientation), the number of block welding passes does not change (taking welding
between blocks into consideration)

Basic welding conditions
Tack welding

Current
P(A)Current
B(A)Voltage(V)

Wire feed(m/min)Welding speed(mm/min)

200

160

11

0.85

80

Adjustments are made so that theroot gap before bridge welding is thesame as far as possible.

Weld metal

Narrowgap

Wide gap

Amount of wire feedless
→ moreResults： 0.4m/min to 0.85m/min

Illustration of welding between uneven gaps

Block welding (first pass)
Bridge welding

Gap
7.5mm

The length of each pass is modified
depending on welding joing between blocks

Non-filler on top of tack welding

Overlap withbridge welding

By connecting with the same
number of block welding passes, agentle welding finishing with only
a little unevenness is achieved.

Block welding (until bridge
welding)
Bridge welding

Welding between blocks

Tack welding to welding between blocks©International Research Institute for Nuclear DecommissioningNo.209

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding
1) Welding test
① Establishment of uneven gap welding〇 Test results
Criteria

Test results✓ Welded portion should be in a soundstate① Should pass the non-destructive test
② Required throat thickness should besecuredRemote welding was carried out with the help of a manipulator for unevengaps, and it wad confirmed that the welded portion was in a sound state.
① Dye PT was conducted after all-around welding. No defects were found.
② Throat thickness (4.3mm or more) was ensured through cross-sectional
macro observation.
TypicalexamplesThroat thickness 1

Throat thickness 2

Throat thickness 8

Throatthickness 3
Throat thickness 4
Throat thickness 5
Throat thickness 6

Throat thickness 7

Verification of dimensions throughcross-sectional macro observation

Throat thickness measurement locations

Status of remote welding using① Dye PT conducted after all-the manipulator

around welding

Measurement
locations

1

2

3

4

5

6

7

8

Measuredvalue (mm)

7.3

10.8

11.5

9.4

8.1

8.2

8.1

11.1

② Results of measuring the throat thickness (Determination: ≧4.3mm) through crosssectional macro observation©International Research Institute for Nuclear DecommissioningNo.210

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding

1) Welding test
② Verification of welding deformation (strain)
The amount of welding deformation is measured while welding and after welding the entire layer to verify the amount of
displacement.
<Results of measuring the amount of displacement>
PCV connection sleeve plate
Equipment
hatch
Welding

PCV connection sleeve plate

Equipment hatch

Approx. +36mm

Approx. +30mm

Welding
location

Approx. -10mm

Approx. -11mm

1. While welding, the gap tends to change in the case of bridge welding
and the displacement of the PCV connection sleeve plate tends toincrease in the case of leg length welding.
2. On the inner side of the equipment hatch, deformation takes place on
the “-” side (equipment hatch side). The deformation is at mostapprox. 14mm.
(The measurement point is located 10mm from the PCV connection
sleeve plate opening.)
3. On the outer side of the equipment hatch, deformation takes place on
the “+” side (access tunnel side). The deformation is at most approx.
36mm.
(The measurement point is located 20mm from the PCV connection
sleeve plate distal end)

Approx. -14mm<Items to be reflected in the actual facility>
Equipment
hatch side

Accesstunnel side・ While welding, the gap changes in the case of bridge welding. The gap should beverified before welding between blocks and the welding program should be
adjusted accordingly.
⇒ Reflection into the work steps
・ The amount of displacement obtained through the tests should be reflected into
the design of the PCV connection sleeve so that the function of the displacement
absorption mechanism is not lost, and reinforcement, etc. should be considered.

Approx. -10.5mm

PCV connection sleeve plate

Displacement absorption
mechanism

The amount of displacement
absorption is likely to be affected
due to welding deformation.

Equipment hatch

Results of measuring the amount of displacement
after welding (representative locations)

Reinforced so that there
is no displacement©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.211② PCV connection sleeve remote installation and welding: (b) Welding
1) Welding test
③ Verification of remote work efficiency
No.

Verification contents / Improvements

Proposed countermeasures directed towards installation of actual facility

Improvement
Items

1

Welding was possible by remote operation using the camera on the welding head.
(2 cameras on the front and back in the direction of travel)

Enhancing visibility by increasing the number of cameras, etc. should be studied as further
improvement.

Visibility ①

2

Teaching pertaining to the welding trajectory needs to be conducted, but it is difficult to
conduct direct teaching using the images from the camera (directly touching by determining
the position of the arm with respect to the teaching point). Direct teaching was conducted while
the worker confirmed with their own eyes.

Offline program should be used.
Offline program refers to creating the welding trajectory and the work position of the manipulator
on a computer and installing it on the manipulator.
If there are any differences in the installed program and the actual conditions, corrections are
made remotely using the camera on the welding head.

Operatingefficiency ①

3Multi-layer filling programs available on the market are used for welding. The change in lengthfrom the initial pass can be specified for each weld pass, but there is a upper limit (99.9mm) tothe change. If the upper limit was exceeded, programs needed to be added.

Even if the upper limit of change in length is exceeded, it is possible to deal with it as long as
programs are added based on the bead length before the upper limit is exceeded. However,attempts should be made to enhance work efficiency by developing multi-layer filling programs inwhich there is no limit to the length.

Operatingefficiency ②

4

It was possible to measure the gap using the welding head.
(Using oscillation)

This should be reflected into the work procedure. In order to further enhance accuracy,
introduction of a touch sensor in the welding head should be studied.

Operatingefficiency ③

5

Welding was possible between uneven gaps when the worker adjusted the amount of wire
feed while verifying with the camera.

Managing the numerical values of the wire adjustment timing by introducing up-slope control anddown-slope control functions should be studied for further improvement.

Operatingefficiency ④

6Since long shot cameras were placed on both sides of the manipulator, the images captured
were from the back of the manipulator thus leading to a blind spot while monitoring work.

The placement of the long shot cameras and the number of cameras should be adjusted.
(Capturing images from the equipment hatch side)

Visibility ②

7With long shot cameras, it was not possible to ascertain the correct work location (correctorientation, distance), such as at which location the beads were in a bad state, etc.

As it is difficult to put a mark on the existing equipment hatch, improvisation is required thatwould make it possible to acquire locational information with the help of a camera (visual), suchas putting a mark on the PCV connection sleeve that is newly made available. Also, an encoder
should be installed on the long shot camera thereby making it possible to acquire information on
the location of the images.

Operatingefficiency ⑤

8Tungsten needed to be replaced (Replaced manually by the worker)

A tungsten replacement equipment should be made available. The welding head should be
remodeled such that it can handle remote replacement.

Equipment ①

9

The welding material (wire) was likely to shift from the target location of the torch while welding
when the direction of the welding head is changed (clockwise to anti-clockwise) or while
welding after the welding head is stowed.

The method of fixing the wire on the welding head (adjustment) should be changed and the wire
feed route should be improved.

Equipment ②

Improvement items were verified with respect to Visibility: 2 cases / Operating efficiency: 5 cases, Equipment: 2 cases.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.212② PCV connection sleeve remote installation and welding: (b) Welding

1) Welding test
SummaryNo.

Results

1

Sound welding was achieved by remotely welding the uneven gap of 7.5mm. The required work management items suchas work procedures, welding conditions, stacking method, etc. were verified.

2

The tendency of the PCV connection sleeve to get deformed due to welding was ascertained.

3

Remote work efficiency was verified, and issues in installing the actual facility were identified.

It is believed that welding is possible up to the 7.5mm gap with the work management achieved through this test. However, it isbelieved that revision of the stacking method and welding conditions pertaining to the 20mm gap is likely to be needed.

For executing the installation of actual facility ・・・
No.

Issue

Response

Response deadline

1

The structure should be such that the tendency to deform due to welding isprovided as feedback while designing the PCV connection sleeve, so that there is
no impact on the displacement absorption mechanism (deformation prevention
elements such as ribs, etc. should be introduced as required).

Study

Until installation of
actual facility

2

The issues identified during verification of remote work efficiency should be
resolved (Equipment suitable for remote operation should be made available).

Study

Until installation of
actual facility©International Research Institute for Nuclear DecommissioningNo.213

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding2) Abrasion test
Items to be verified
・Verification of polishing work
carried out by means of remote
operation

Items to be monitored, measured andrecorded① Selection of polishing tool
② Polishing guidelines

Criteria✓ Polishing that does not hinder the
fluorescent PT should be possible

Examples of false defects due to areas left unpolished<Polishing tools using which the results of the fluorescent PT were good>

Location for verifying polishing work
Verified at typical positions(downward, sideways, upwards)(Location enclosed by the red circle)

Verification of polishing work
・ Polishing position
・ Rotational speed
・ Pressing force
・ Progression speed

Nippon unit
DiamondNylon brushNippon unit
Metal brush(Thistle type)

3M
Radial bristles
Margaret disc

Selection of polishing tool suitable for the shape of
the actual facility
Considering the approach towards the welded part, apolishing tool selected in FY2020 or a tool that issuitable for the approach is selected.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.214② PCV connection sleeve remote installation and welding: (b) Welding2) Abrasion test
〇 Polishing head
Tool changer
Active compliance equipment(1) Model: AFD310-2(2) Output: 267N(MAX.)

Cooling water
circulating hose

(3) Maximum payload: 27.2kg(4) Sliding section: 20mm(5) Mass: 5.5kg
Detects reaction force along withsupporting the water cooling spindle
motor, and automatically slides the spindle
motor so that the magnitude of reaction
force becomes constant.
This prevents the manipulator overload.

Sliding direction
Water cooling spindle motor(1) Model: STC1503-BT30(2) Output: 2.2kW

Polishing head (Manufactured by Push Corp
Reaction force buffering equipment)(3) Torque: 3.5N.m(4) Rotational speed: 60 to 15000rpm(5) Mass: 12.7kg©International Research Institute for Nuclear DecommissioningNo.215

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding2) Abrasion test
〇 Test results
Criteria

Test results✓ Polishing that does not hinder the
fluorescent PT should be possible

It was confirmed that polishing is possible using the manipulator withouthindering the fluorescent PT.

External
appearance of thebead after polishing

Bevel brush
・External diameter:
φ200/wire diameter: 0.3mm

External appearanceof the bead after
polishing

Status of polishing ②

Status of polishing ①<Polishing conditions>

Metal brush
・External diameter:
φ30/wire diameter: 0.3mm

Polishing conditions

Rotational speed(rpm)

Feeding speed

Pressing force

Range of access

Bevel brush

500

100mm/min

20N

Area excluding the scaffolding seal cover side

Metal brush

2000

100mm/min

20N

Complete periphery can be polished©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.216② PCV connection sleeve remote installation and welding: (b) Welding2) Abrasion test
SummaryNo.

Results

1

The polishing tools were selected, polishing conditions for each tool were verified, and it was confirmed that the entire
welded portion can be polished. Also, it was verified that the finishing achieved after polishing does not hinder
fluorescent PT.

2 types of polishing tools were selected, but the consumption of the metal brush was large and it needed to be replaced
frequently. Hence in the actual facility, polishing will be carried out mainly using the bevel brush and the metal brush will be
used only in areas where the bevel brush cannot be used.
For installation of actual facility ...
No.

Issue

Response

Response deadline

1

Visibility during work needs to be ensured. The placement of the camera that canverify the tool tip at an appropriate location and placement of the long shot
camera need to be studied.

Study

Until installation of
actual facility

2

Whether offline program is applicable to polishing tools that have a soft tip needs
to be verified (Development of polishing work steps).

Study

Until installation of
actual facility

3

Introduction of equipment for automatic replacement of polishing tools

Study

Until installation of
actual facility

4

Covering as a countermeasure for polishing dust generated while polishing, andcollection of polishing dust

Study

Until installation of
actual facility©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.217② PCV connection sleeve remote installation and welding: (b) Welding3) Fluorescent PT test
Items to be verified

Items to be monitored, measured andrecorded・Verification of applicability to actual
facility① Blasting conditions of the penetrant(Pressure, distance, blasting time)② Surplus liquid washing conditions(Pressure, distance, blasting time)③ Identification of indication

Criteria✓It should be possible to detect the defect(Implemented using the test piece#)✓Remote operation should be possible(Implemented through full-scale test)

・ Penetrant and cleaning water is blasted by means of a spray
・ Parametric study of the blasting time and the distance from the specimen while blasting the penetrant andcleaning water is conducted to verify the test conditions.
・ The status of the fluorescent PT is conducted on the full scale test piece under the verified test conditions# If defects are detected by means of the
full-scale dye PT, it is verified whether
similar defects can be detected bymeans of the fluorescent PT.

(verified for the typical position)
Cleaning water +compressed air

Cleaning solution +compressed air

Installed on the Daihen
VR50 robot arm
Solenoid valve unit
Tilting unit

Camera + nozzle unit
Fluorescent PT liquid +compressed air

Fluorescent PT verification locations(Locations enclosed by the red circle)

Inspection equipment

Testing by setting conditions©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.218② PCV connection sleeve remote installation and welding: (b) Welding3) Fluorescent PT test
〇 Test results
Criteria

Test results✓It should be possible to detect thedefect(Implemented using the test piece)✓Remote operation should be possible

・Conditions under which defects can be detected were verified using the test piece・It was verified that observation is possible during the fluorescent PT by remotely
operating the manipulator〇 Fluorescent PT procedures
PolishingWashingDryingFluorescent penetrant Surplus liquid removal

DryingObservation

Weld beadOperation panel
Blackout
curtain

Location for
Fluorescent PT
External appearance of the testing facility

Status of blasting fluorescentpenetrant

Surplus liquid removal (UV radiation)

Observation (Camera image of thefluorescent PT head)<Main working conditions (conditions established based on the results of testing by setting conditions)>
Work Items

Washing

Working
conditions

Movement: 30mm pitch
Blast pressure: 0.2MPa
Blasting time: 0.3s/cycle

Drying air
Moving speed: 10mm/s
Blast pressure: 0.1MPa

Penetrant blasting
Movement: 30mm pitch
Blast pressure: 0.2MPa
Blasting time: 0.3s/cycle

Surplus liquid removal
Moving speed: 10mm/s
Blast pressure: 0.25MPa

Drying air
Moving speed: 10mm/s
Blast pressure: 0.1MPa

Observation
Movement: 30mm pitch
Observation: 30s/location©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.219② PCV connection sleeve remote installation and welding: (b) Welding3) Fluorescent PT test
SummaryNo.

Results1

Conditions under which defects can be detected were verified.

2

It was verified that the fluorescent PT using the typical position can be observed by remotely operating the manipulator.

It was verified that remote operation is possible using the manipulator and the working conditions for the Fluorescent PT wereverified as well. However, reasonable options will be studied at the stage when the safety requirements pertaining to tool
welding are determined, including the option of using only VT that does not generate any liquid waste.

In order to use the fluorescent PT in the actual facility
No.

Issue

1

Establishment of the installation procedures including the method of waste liquid
treatment to be used2

Response

Response deadline

Study

Until installation of
actual facility

Development of inspection head for installation of actual facility (remodeling of the test
head)

Development

Until installation of
actual facility

3

Method of judging (determining acceptance/rejection) the magnitude of the indicationand specification and recording of the location of detection

Study

Until installation of
actual facility

4

Prevention of rust after fluorescent PT (Verification of the effect of cleaning waterconsisting of an anti-rusting agent)

Study

Until installation of
actual facility©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.220② PCV connection sleeve remote installation and welding: (b) Welding4) Dimension measurement
Items to be verified

Items to be monitored, measured
and recorded

・Verification of guidelines for remotedimension measurement

・Dimension measurement
guidelines
・Cross-sectional observation

Criteria✓ Accuracy of dimension measurement
should be ascertained・ The “throat thickness” is measured by letting the welding head touch the electrode.

Simulated PCV connection sleeve

・ After welding, cross-sectional observation is carried out to verify the accuracy of the dimension measurement by means of electrode touch.

Simulated PCV
equipment hatch

Referencelocation

ReferencelocationA

Welding head

Remembering the reference
location before welding

B

Specified throat thickness
dimensions: 4.3mm or more
The movement of the tip from the reference location before welding is measured.
The throat thickness is calculated from the movement of the electrode tip (A-B).
©International Research Institute for Nuclear DecommissioningNo.221

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]② PCV connection sleeve remote installation and welding: (b) Welding4) Dimension measurement〇 Test results
Criteria

Test results
・The error is -2.0 to 1.3. The welding head is almost underestimated, but as the crosssectional macro includes weld penetration, it is believed to have roughly the same value.

✓ Accuracy of dimension
measurement should be ascertained

Simulated PCV connection sleeve

Throat thickness 1
Throat thickness 2

Throatthickness 3

・In the case of throat thickness 4, it is believed that the error in measurement was larger
since the measurement position at the welding head was not from the central axis directionof the equipment hatch.

Throat thickness 8

Throat thickness 4
Throat thickness 5

Simulated PCV
equipment hatch

Referencelocation

Referencelocation

Throat thickness 6

Calculated by A-B

Welding head

Throat thickness 7

Measurement by means of
the cross-sectional macro

Measurement based on the stroke of the welding head

Measurement locations<Comparison of the dimension measurement results of the welding head and during cross-sectional observation>

Unit： mm

Measurement
locations

1

2

3

4

5

6

7

8

Welding head

6.2

8.8

11.3

10.7

8.1

8.4

7.2

10

Cross-sectional
observation

7.3

10.8

11.5

9.4

8.1

8.2

8.1

11.1

Error

-0.9

-2.0

-0.2

1.3

0

0.2

-0.9

-1.1

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.222② PCV connection sleeve remote installation and welding: (b) Welding4) Dimension measurement
SummaryNo.
1

Results
The measurement accuracy of the throat thickness was verified in the case of fillet welding using the welding head.

As the throat thickness turned out to be larger than the specified dimensions if manufactured according to the present
stacking procedures, it is believed that the throat thickness achieved using the welding head can be controlled (determinationof minimum dimensions) in the actual facility as well if the measurement position is controlled.

For installation of actual facility ...
No.

Issue

Response

Response deadline

1

Controlling the measurement position (Particularly when the welding position is
not perpendicular to welding)

Study

Until installation of
actual facility

2Introduction of the tungsten replacement equipment (Is replaced with newtungsten before measurement)

Development

Until installation of
actual facility©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.223② PCV connection sleeve remote installation and welding: (b) Welding5) Cold crack test

PCV connection sleeveMaterial： SM400 (P1)
Sheet thickness: 36t

Concerns about cold cracks
PCV equipment hatch
Material： SGV480 (P1)
Sheet thickness： 90t (1F-1)

Verification of the formation of cold cracks(Material
usedVerification: SGV480)
Items
test
Verification contents
Verificationtest

Lap joint welding test
(JIS Z 3154)

Short bead test
(Bead-on-plate test)

Verification
contents

Verification of formationof cold cracks due tofillet welding

Verification of formationof cold cracks assuming
there are interruptions in
welding

Plate
thickness

40t

40t

G≒7.5mm

External
appearanceof test piece(Afterwelding)

Welding： TIG welding
Welding material: TG-S50

Verification
methodSurface PT, Crosssectional observation

Surface PT, Crosssectional observation

Crosssectional
picture<Test results>
Cracks were not found in any of the tests©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.224② PCV connection sleeve remote installation and welding: (b) Welding5) Cold crack test
SummaryNo.

Results

1

No cracks were found during the test for verifying formation of cold cracks using material equivalent to the actual facility.

The material of the test piece was equivalent to the actual facility and the test was conducted without pre-heating or thermal
processing. But cracks were not formed. It is believed that cracks were not formed because the method of fillet welding wasused due to which the binding force was comparatively small. But the condition of the material at the actual facility is unknown.
It is believed that if the characteristics of the material in the actual facility can be ascertained, even if the actual facility is
installed without pre-heating, the risk of cold cracks will be low.

For installation of actual facility ...
No.

Issue

Response

Response deadline

1

Ascertaining the characteristics of of the materials, such as verifying the Mill Test
Report pertaining to the existing equipment hatch in each unit

Verification

Until installation of
actual facility©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.225② PCV connection sleeve remote installation and welding: (b) Welding(6) Summary of test results➢ The feasibility of remote welding, polishing, fluorescent PT, dimension measurement (throat thickness
control) was verified for a welding gap of 7.5mm or less by conducting full-scale tests.

➢ As a result of conducting tests for verifying the formation of cold cracks, it was confirmed that cold
cracks do not form even if there is no pre-heating or thermal processing. It is believed that the risk offorming cold cracks is low while installing the actual facility even if the installation is carried out without
pre-heating, but as the properties of material in the actual facility is unknown, if pre-heating has to beomitted while installing the actual facility, the characteristics of the material in the actual facility need tobe verified such as by checking the Mill Test Report pertaining to the existing equipment hatch, etc.
➢ Issues in actual facility application were identified from the test results and consolidated. The identified
issues including the work efficiency of remote operation need to be studied and resolved before theactual facility installation work.

Further, technical verification such as pertaining to welding work, inspection method, etc. is being
carried out, but for application to the actual facility, coordination and discussions (determination of preconditions) need to be carried out pertaining to compliance with technical standards (equipment class,applicability of the Operator’s inspection on welding (including witnessed inspection), etc.).

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.226② PCV connection sleeve installation and welding by remote operation[Development Schedule]: Planned: Actual

FY2021

FY2022

Study items
4

Major milestones

5

6

7

8

9

10

11

12

Interim Report
▼

1

2

3

4

5

6

Interim Report
▼

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final report▼

1. Conceptual study
2. Element testplanning

3. Test preparation /Manufacturing oftest equipment
4. Element tests
5. Summary

Remarks©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.227② PCV connection sleeve installation and welding by remote operation: (a) Remote installation summary➢ In FY2021, the requirements (pre-conditions) for remote installation of the sleeve, results ofstudying the concerned delivery method and equipment were consolidated. “The method ofdelivering the unit in its entirety” which is the same as the method used for delivering the main
access tunnel was selected, and the issues and items that need to be verified through tests, etc.
were consolidated.
➢ Based on the results consolidated as mentioned above, the specifications pertaining to the remotesleeve installation equipment, sleeve structure, opening part, installation procedures, etc. werestudied using mock-ups. The actual facility (assumed) and the mock-up equipment were comparedand the results were compiled. Test plans including sensing were created, and a gap of 20mm orless (target 7.5mm or less) was established as the judgment criteria.
➢ Preparations were made for a full-scale test equipment and facility for remote installation of thesleeve, and tests for verifying the feasibility related to the procedures for remote installation of thesleeve and the equipment were conducted.
➢ As a result of the tests, it was verified that the target of 7.5mm or less is met. Also, issues inapplication to actual facility were identified and consolidated.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.228② PCV connection sleeve remote installation and welding: (b) Remote welding summary➢ The methods of responding to the issues pertaining to remote welding of the sleeve consolidated
during the FY2019-20 subsidy project were studied in FY2021, and issues as well as items thatneed to be verified through tests, etc. were consolidated.
➢ Items to be verified, monitored, measured and recorded were substantiated through the welding,polishing and fluorescent PT (inspection) tests, and judgment criteria were established.
➢ Preparations were made for element test equipment and facility for remote welding of the sleeve,and element tests were conducted for verifying the feasibility related to the procedures for remotewelding of the sleeve and the equipment.
➢ Feasibility of remote welding for a welding gap of 7.5mm or less was verified by conducting fullscale tests. However, there is a possibility that the welding conditions for a welding gap of 7.5mm
to 20mm will need to be revised. Also, maintenance was studied to verify applicability to the actual
facility.
➢ Issues in application to the actual facility were identified from the test results and consolidated.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.229③ Installation of shield
Studies on access equipment, such as the access tunnel (a tunnel type structure for accessing theinside of the PCV), to be used when the side access method is adopted, have been carried out for
further increasing the retrieval scale of fuel debris and reactor internal structures. The retrieved fueldebris, etc. will be temporarily placed inside the access equipment. Considering that the areaaround the structures being installed will be used as the work environment, it is necessary to
reduce the radiation dose. Thus, the access equipment becomes a large and heavy object withshielding functionality. Hence, in order to reduce the load on the floor of the R/B, ancillary facilities,
etc. required for transportation to the inside of the R/B, etc., streamlining of the structure of theshield of the access equipment, and the transportation / installation methods need be studied, anddevelopment needs to be carried out as needed.
In order to safely and efficiently carry out the work of establishing the shield under high radiationdose by remote operation, first, the pre-conditions required for assessing the shielding functionality
including the state of existence, the type of radiation source, etc. of the inside of the PCV and of theretrieved fuel debris, etc. will be studied and compiled. Next, studies including exposure dose
evaluation will be carried out pertaining to the procedures, the transportation and installation
method, including the shielding structure, addition of shield, etc. based on the strength of the R/B
structure and the on-site workability. Subsequently, a simulated test piece of the access equipment
on which the shield will be installed, will be manufactured, and viability will be verified andevaluated through verification tests for verifying the feasibility such as a manufacturing capability,
etc., and thereafter the technology required for reasonably installing the shield on the accessequipment will be developed.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]

No.230③ Installation of shield
Table of Contents⚫

Status of studies conducted up to FY2020, issues, implementation details and results

⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫

Consolidation of pre-conditions
Shielding thickness between the access tunnel and the cart
Organization of the purposes of additional installation of shield
Study of the methods for additional installation of shield
Image of actual facility
Test plan
Test equipment
Test results
Issues⚫
⚫

Development schedule
Summary©International Research Institute for Nuclear DecommissioningNo.231

6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]③ Installation of shield[Status of studies conducted up to FY2020]⚫ Some of the conditions for studying the shield thickness were revised and a simple study of the shield thickness was
Temporary
conducted.
building area
Reactor building⚫ Conceptual study of the frame structure was conducted.
Large crane[Issues]
Large ancillary facilities, since the mass to be delivered is large. Interference during post-processing.
(Access tunnel weight (large) → Delivery weight including CW (large) → Ancillary facilities (large))
Access tunnel⚫ Feasibility of the method for additional installation of shield by complete remote operation or partial remote
operation.
⚫ Structure with minimal defects and assurance of shielding performance (method of verification atCounter weightcompletion)
Multi-axial heavy cart
Approx. 700t(1F-1)⚫ The structure of the access tunnel shield, the transportation and installation method need to be
streamlined.
Total delivery weight at present:⚫ Reduction in weight while maintaining rigidity of the delivery frame

Approx. 1100ton(1F-1)

1mSv/h or
0.5mSv/h以下
lessaccess tunnel: Approx. 425ton

BSW
AT load approx.
AT荷重
235ton
約235ton(Approx.
m2
45ton/m2)（約45ton/m2）

Debris
UC搬送デブリtransported in
100kg
UC
100kg
R/B load limit
approx.
R/B荷重制限
750ton/m2
m2
約750ton/m2

150Sv/h300[Implementation details]⚫ The preconditions required for assessing the shielding
functionality including the state of existence, the type, etc. of theradiation source such as the inside of the PCV, the retrieved fueldebris, etc. are studied and compiled.
⚫ The transportation and installation method and procedures
including the additional installation of shield, etc., the shielding
structure, etc. based on the strength of the R/B structure and onsite workability are studied including exposure dose evaluation.
⚫ A simulated test piece of the access tunnel on which theshield will be installed, is manufactured, the element plan iscreated, and feasibility such as manufacturing capability, etc. isverified.

現在の検討条件(例：1号機)
Current study
conditions (Example: Unit 1)
Access tunnel (AT)
アクセストンネル（AT）
Weightof the main body of the
AT本体重量約425ton

Outer
wall of theOuterwall of R/B
R/B外壁
増設建屋外壁additional building
OutsideR/B内R/B
Inside
R/B外
R/B

PCV

AT load approx.
AT荷重215ton(Approx.
約215ton90ton/m2)
m2（約90ton/m2）

Load R/B1階全体床耐荷重
capacity of the entire floor of R/B
first floor
approx. 1.22 m
to24.88ton/m2
約1.22～4.88ton/m2

BSW load limit
BSW荷重制限
approx.
750ton/m2
m2
約750ton/m2[Expected outcome]⚫ Presentation of a reasonable method for
installing the access tunnel shield.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]③ Installation of shield

No.232[Consolidation of preconditions]
The pre-conditions for calculating the shielding thickness were consolidated. The source strength for evaluation was calculated
by back calculating based on the actual measured value.
Further, as the work to be performed in the R/B is unknown, this study was conducted assuming workers will enter inside the R/B.
Items

Conditions

Target plants

1F-1, 2, 3

While transporting fuel debris
inside the access tunnel

Remarks

No (People are cleared out)

Entry inside R/B
During regular times(Other than those mentioned
above)

Yes

Inside PCV

Source strength is calculated for evaluation

Inside AT

Fuel debris inside the Φ200 unit canConcrete2.15 (g/cm3)Iron

7.8 (g/cm3)

Polyethylene (PE)

0.92(g/cm3)

Target dose rate on the accesstunnel surface

Inside R/B

1.0mSv/h (During regular times)

Evaluation points

Height10cm, 120cm above the floor

Data from Unit 1 is used

Radiation source

Material density

Evaluation carried out with 30kg/can x 2(Note)
・ The target dose rate was tentatively considered to be 1.0mSv/h. It needs to be finalized eventually while comparing with the quantity of fuel debris transported (dose rate), shielding
thickness, and air dose rate inside the R/B.
・ As the impact of neutrons from inside the PCV is smaller than that of the gamma rays, the impact was verified using the actual measured value. The neutrons when the fuel debris
passes through the access tunnel were evaluated.

The shielding thickness of the access tunnel was determined based on the above conditions, and the additional installation method and installation equipment were studied.
©International Research Institute for Nuclear DecommissioningNo.233

6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]③ Installation of shield[Consolidation of preconditions]Shielding evaluation was carried out under the following conditions.

Items

Unit

1F-1

1F-2

1F-3

Shieldingevaluation
conditions

Initial concentration

wt%

3.7

←

←

3.7

Burn-up

GWd/tHM

40.17240.55740.49941

Specific output:

MW/tHM

20.0

25.3

←

20.0 Note)

Cooling period

years

20

←

←

20

Fuel debris composition(weight)―

UO2(Weight calculated
assuming UO2=1t)

←

←

UO2
(Weight calculated
assuming UO2=1t)

The following was used for calculating burn-up.
⚫ Calculation code: ORIGEN2.2 UPJ⚫ Cross-sectional area library: BS340J33⚫ DECAY library: JNDECAY33.LIB⚫ Photon library: gxuo2brm.lib

Note) Studied based on Unit 1, as there is almost no impact.

©International Research Institute for Nuclear DecommissioningNo.234

6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]③ Installation of shield[Evaluation results] Shielding thickness: Wall/Ceiling 300mm, Floor 110mm (Quantity of fuel debris 30kg×2)[30kg/can x 2 cans, evaluation height: 10cm, keff=0.95]

High γ radiation dosein the vicinity of the floor

Gamma rays
Gamma rays inside PCVDose rate (mSv/h)Secondary gamma rays

Surface

Surface
Evaluation location[30kg/can x 2 cans, evaluation height: 10cm]

Evaluation location[30kg/can x 2 cans, evaluation height 120cm]

Dose rate (mSv/h)

Dose rate (mSv/h)

Evaluation height:
The position of the ADP
during work is assumed.
⚫ 10cm: During work on
the floor surface (while
laying on the floor)⚫ 120cm: During regularwork
Evaluation location:⚫ Distance from theaccess tunnel surface

Neutron beam
Secondary gamma
rays
Gamma rays
Gamma rays inside
PCV

Neutron beam

Dose rate (mSv/h)

Addition ofshielding[30kg/can x 2 cans, evaluation height: 120cm, keff=0.95]

SurfaceShielding thickness:
・ Wall/Ceiling 300mm is
the shielding thickness
obtained through simple
calculations when the studyof the access tunnel began.
・ The floor surface
thickness is an approximate
thickness calculated fromthe structural design

High neutron
beam dose

Addition ofneutron shielding
Surface

Evaluation location

Evaluation location

1mSv/h or less is met even with a shielding thickness of 250mm.

Based on the results of dose comparison between shielding thickness 300mm/250mm, it isexpected that by shielding neutrons, 1mSv/h will be met even if the access tunnel wall andceiling are 200mm and the floor is 110mm.
©International Research Institute for Nuclear DecommissioningNo.235

6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]③ Installation of shield[Shielding thickness between the access tunnel and the cart]
The shielding thickness required for the access tunnel considering the thickness (75mm) of shielding thatcan be installed on the cart inside the access tunnel, is given below (red frame).
No.

Radiation source①

Dose from inside the PCV(Regular times)②

Dose from fuel debris that isbeing transported(Temporary)

Required shielding capability calculated basedon the dose

Shielding capability required for the main bodyof access tunnel

Floor: 110mm (@ iron)

Floor: 110mm (Not affected by the cart shielding)

Other than floor: 170mm (@ iron)

Other than floor: 170mm (Not affected by the cartshielding)Floor: 110 + αmm (@ iron)

Floor: 35 + αmm (Considering 75mm of cartshielding)

Other than floor: 200mm (@ iron)

Other than floor: 125mm (Considering 75mm of cartshielding)

250mm (@ Polyethylene)

Perimeter: 0mm

γ raysNeutronbeam

Based on the above, the shielding thickness of the access tunnel is assumed to be 110mm for the floor
and 170mm for areas other than the floor. The cart is assumed to bear the load of 30mm thick iron shielding
and 250mm thick polyethylene shielding.

Iron

Cross-section(At present) Cross-section of the access tunnel

Shielding of thetransportation cart
inside the accesstunnel
PE: 250mm
Iron: 30mm

(After modifications) Cross-section of the access tunnel©International Research Institute for Nuclear DecommissioningNo.236

6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]③ Installation of shield[Evaluation results]
Shielding thickness (Access tunnel): Wall/Ceiling 170mm (Iron), Floor 110mm (Iron)
Shielding thickness (Cart inside the access tunnel): Perimeter 30mm (Iron), Perimeter 250mm (PE)⚫ γrays from inside the PCV are dominant.
⚫ The dose from the fuel debris passing from inside the access tunnel is extremely small.

Note) The dose from inside the PCV has
been briefly studied. Hence attenuationof the distance has not been included.

Secondary gamma rays

Neutron beams

Secondary gamma rays

Primary gamma rays

Gamma rays inside
the PCV

Primary gamma rays

Gamma rays inside
the PCV

Dose rate (mSv/h)

Dose rate (mSv/h)

Neutron beams

Surface

Surface

Evaluation height:
The position of the ADP during
work is assumed.
⚫ 10cm: During work on thefloor surface (while laying on
the floor)⚫ 120cm: During regular work
Evaluation location:⚫ Distance from the accesstunnel surface

Evaluation location

Evaluation location(a) 10cm above the floor(b) 120cm above the floor

Evaluation conditions: Fuel debris: 30kg/can × 2 cans, keff: 0.95

It was verified that the target dose of 1.0 mSv/h or less is met.
©International Research Institute for Nuclear DecommissioningNo.237
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Organization of the purposes of additional installation of shield]
Purpose of the method for additional installation of shield
Avoiding interference with the work ofconstructing the additional building(Reducing the load of ancillary equipment)①②

Study / Results

Implementation of shielding evaluation→ Total weight approx. 260ton, maximum weight of the unit approx. 74ton

Simplification of hoisting equipment
Reduction of counter weight

Study of the structure of theadditionally installed shield→ Maximum weight of the unit approx. 45ton
Hoisting equipment weighing 50ton or more is required→ Ground improvement, etc. is necessary.

Addition(Comments during
deliberations, etc. at IRID)

Modification of the hoisting equipment→80 to 90ton can be handled using CC##Crawler crane
Additional shielding is installed as required
after ascertaining the status inside the PCV

Access tunnel
construction
schedule

Consolidation of design
conditions

Maximum weight 115ton →74ton→ As this was 2/3 of theoriginal maximum weight,
the hoisting equipment was
modified once again

Prospects of feasibility were obtained.

Examination of method ofadditional installation
Designing of actual equipment(Structure that enables
additional installation)

Investigation: It was found that the dose washigher than the design conditions.

Manufacturing

Installation

Installation of additionalshielding to compensate forlack of shielding capability
after installation

Operation# The design, etc.
will not be
reworked.

©International Research Institute for Nuclear DecommissioningNo.238
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Study of the methods for additional installation of shield]
The methods for additional installation can be classified into a. Method of inserting inside the frame, b. Method of
installing from the outside, and c. Method of installing from the inside.
a. The proposal to insert a shield inside the frame. The method of inserting steel balls or iron plates inside the frame
can be considered.
b. The proposal to add a shield from the outside. The method of placing load on the main body of the access tunnel oron the floor surface of the R/B first floor can be considered.
c. The proposal to install blocks from the inside. Installing blocks, etc. is being assumed, but as the shield needs to beinstalled around the utility, the size of the blocks needs to be reduced. As the blocks are expected to be large innumber, c. will be exluded from the study.

t=110mmb

UtilityArea*ct=170mm

t=170mm

Additional shield
Illustration

t=170mm

t=170mmat=170mm

t=170mmFrame

t=110mm* Same on the other side

As “c” is believed to have many issues, a and b will be studied.
©International Research Institute for Nuclear DecommissioningNo.239
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]○： Feasible△： There are issues
×： Not feasible③ Installation of shield[Study of the methods for additional installation of shield]
a. Proposal to insert the shield

Additional shield

Spout

Proposal to deliver a planar shielding

Proposal to fill spherical shielding

Proposal to cast

Proposal to deliver a planar shielding
from the additional building side. For the
curved part, reducing the length of theshielding for delivery is considered.

Proposal to pump spherical shields andfill them into small chambers separated
by iron plates, etc. The spherical shields
are filled in the chambers by using
technologies such as shot blasting, etc.

Proposal to cast (pour) melted shielding
material.

Illustration

Overview⚫
Issue

Evaluation⚫
⚫

Connection accuracy of the units of
the access tunnel (Transfer of theadditionally installed shield)
Delivery of the curved part
Emergency response (Difficult tohandle if it gets stuck in the middle)

x

⚫
⚫
⚫

Pumping method
Verification of the filling rate
(Shielding performance)△⚫
⚫

Decline in shielding performancedue to formation of cavities(Shielding performance cannot beensured)Deformation due to heat
The casting equipment is largex

The proposal to fill spherical shielding / blocks proposal / curtain proposal were evaluated as “△”As there are many unknowns such as the filling rate, etc. in the case of the proposal to additionally install
spherical shields, its feasibility needs to be verified by conducting element tests.
©International Research Institute for Nuclear DecommissioningNo.240
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Illustration of actual facility / Proposal to fill spherical shielding]An illustration of the actual facility is indicated. The method of setting up several cells for additional installation ofshields, and pumping spherical shields was studied. Although cells are not indicated on the wall surface in the bird’s eyeview (it has been shown as a single unit), in reality, the plan is to divide the area into multiple cells. The hose forpumping the shields is sent in up to the prescibed location by sliding it on a rail.

Space where granular shields are pumped

Grating

Bird’s eye view

Hose

Status uponfilling steel
balls

Tunnel opening

Details A

Tunnel opening

Rail(Grating)

Cross-section
Cell
300#
mm

Illustration of the pumping of the shields# Although a thickness of 300mm is shown inthe drawing, in this study the shield to be
additionally installed is considered to beabout 130mm thick.
©International Research Institute for Nuclear DecommissioningNo.241
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test plan]

The following items to be verified are verified by conducting tests.
Items to be monitored, measured
and recorded

Criteria(Target value)

Items to be verified

Implementation details

Filling rate

The rate of filling the spherical shields into the test
cell is verified. Further, the volume of the test cell ismeasured by filling water into it.

➢ Volume of the test cell
➢ Weight of the filled shielding
material

Filling status(Wall cell)

The status of filling the shields is verified from thewindows provided alongside the cell. Windows forverification are provided at 3 locations: top, middle
and bottom.

➢ Filling status－

Filling status(Ceiling cell)

The status of filling the shields is verified from thewindow provided on top of the cell.

➢ Filling status－

Filling status(Wall cell, Ceiling cell)

The status of the top portion of the filled shielding
material (formation of the heap) is verified.

➢ Angle of repose

Target filling rate: 60%(Before operations such as
tapping, etc.)－(Reference measurement)

Remarks
・Target value 60%: Considering that the required shielding thickness is 300mm based on the studies conducted so far, the configuration used was:Access tunnel 170mm + Cart 75mm (Maximum) + Additionally installed shield approx. 75mm (130 × 0.6) (Total 320mm).
・Angle of repose: The (maximum) angle of an inclined plane at which accumulated particles and granular material (coal powder, etc.) remain stable anddo not collapse of their own accord.

©International Research Institute for Nuclear DecommissioningNo.242
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test equipment (Illustration)]
Mobile scaffolding
View port
Wall cell

Ceiling cell
Hose holding fixture
Frame
Exhaust duct
(Tied up with frame)
Frame for the hose
Hose holding member
Blast hose (20m)
Shutter control wire (20m)
Camera cable (20m)
Steel ball blasting equipment

Exhaust fan (as required)

Palette cart

Blast hose
(Shielding cell ceiling part to be installed during construction)

Released to the outside

Camera shutter lever
Push button (Cable 20m)

Control panel©International Research Institute for Nuclear DecommissioningNo.243
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Complete view of the equipment and volume of each cell]
Indicator
Hose rail

Wall cell
Hose rail
Indicator

Complete view of the equipment
Wall cell (Parameter:
reinforcement)

Ceiling cell (Parameter: width)
Cell
name
Volume
(L)

200

300

400

500

AbsentZigzagParallel rowsSingle
row

27

39

51.5

63.5

176

166

165

177.5

Ceiling cellNote) Verified using a volume flowmeter by filling the cell with water.
©International Research Institute for Nuclear DecommissioningNo.244
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test equipment (Outline drawing of ceiling cell)] Test is conducted using the width direction as the parameter(200 to 500mm)
CameraHose rail

Hose rail

200 cell

200 to 500#(mm)

Indicator

500 cell

400 cell

500 cell

400 cell300(mm)Blasting
hose

300 cellApprox. 500(mm)300 cell

Cross-section(Front surface ofthe equipment)

Cross-section (Lateral surface ofequipment)

200 cellOutline drawing of ceiling cell
Lateral surface of equipment# Width of each cellis as follows
200 cell: 200mm
300 cell: 300mm
400 cell: 400mm
500 cell: 500mm©International Research Institute for Nuclear DecommissioningNo.245
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test equipment (Outline drawing of wall cell)] Test is conducted using the position of the reinforcement
beams as the parameter
Hose rail
Blastinghose

Hose rail

CameraIndicator

3100(mm)

Filling statusverification
window
Reinforcement
beam
Lateral surfaceof equipment

100(mm)Single row cell

Cell with no
beams

Parallel rows cell

Zigzag cell

Cross-section (Lateralsurface of equipment)

Cell with nobeams

Approx.
500(mm)Cross-section(Front surfaceof theequipment)©International Research Institute for Nuclear DecommissioningNo.246
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test equipment (Steel ball blasting equipment)]

Manipulator

Compressed air

Steel balls Steel balls (Φ1.7mm)
blasting port

Steel ball tank

Regulator
Steel balls
Blasting hose

0.2MPa©International Research Institute for Nuclear DecommissioningNo.247

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test equipment (Blasting nozzle)]
Straight nozzle
CameraRail hanger

Blasting hose

Installation
statusRail

Distal end of theblasting hose
Straight nozzle

Elbow nozzle
Indicator

Camera image©International Research Institute for Nuclear DecommissioningNo.248
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Fundamental test (1) Filling rate verification test]
Test guidelines: Fill (manually) the acrylic case with filler material, and measure the weight of
the filling material. Verify the filling rate.
Acrylic case (t=3mm)

Simulated shielding material(NB-200 Average particle size
Φ1.7mm)Filling status

Items

Measurements

Apparent density

Filling rate

Volume of acrylic case

2.73L

Weight before tapping

12.34kg

4.52g/cm3

57%

Weight after tapping

13.08kg

4.79g/cm3

61%

Remarks

Calculated based oninternal dimensions

ー©International Research Institute for Nuclear DecommissioningNo.249
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Fundamental test (2) Filling rate verification test]
Test guidelines: Fill with each nozzle until the indicator for verifying the height is covered, andonce the top surface of the filling settles, weigh the filling material. Verify the filling rate when theequipment is used. Further, manually add filling material in case its level is lower than the waterlevel during volume verification.

Indicator

Blasting
hose

500 cell

400 cellApprox. 500(mm)

Approx. 500(mm)

Indicator

Blasting location(Cell center)

500 cellApprox. 500(mm)Partition

400 cell

300 (mm)

Partition

300(mm)Blasting
hose

Blasting location(Rear wall ofcell)Approx. 500(mm)

If the 500 cell is being filled (Left: straight nozzle, Right: elbow nozzle)©International Research Institute for Nuclear DecommissioningNo.250
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Fundamental test (2) Filling rate verification test]
Test guidelines: Fill with each nozzle until the indicator for verifying the height is covered, and once the top
surface of the filling settles, weigh the filling material. Verify the filling rate when the equipment is used.
Further, manually add filling material in case its level is lower than the water level during volume verification.

Water level during volume
verification

Filling status (Ceiling cell / 500m width)
Apparent density (Fillingrate)

Straight nozzle

Elbow nozzle

Ceiling cell (500 cell)

4.94g/cm3 (63%)

4.83g/cm3 (62%)

Wall cell (Cell with no beams)

4.94g/cm3 (63%)

4.97g/cm3 (64%)©International Research Institute for Nuclear DecommissioningNo.251
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (1) Selection of nozzle] (Verified with the help of the ceiling cell)
Test guidelines: Blast the filling material until the indicator for verifying the height iscompletely covered. Verify the blasting time, quantity filled (target cell/other) and the statusof filling.

Indicator

500 cell

400 cellApprox.
500(mm)Approx.
500(mm)Blasting
hose

Indicator

Blasting location(Cell center)

Partition

500 cell

400 cellApprox.
500(mm)Approx.
500(mm)

300(mm)Partition

300(mm)Blasting
hose

Blasting location(Rear wall ofcell)

If the 500 cell is being filled (Left: straight nozzle, Right: elbow nozzle)©International Research Institute for Nuclear DecommissioningNo.252
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (1) Selection of nozzle] Test results ①(Ceiling cell)
CameraField ofview ofthecameraIndicator

500 cell / elbow / nozzle initial
position

200 cell / elbow / camera image

Illustrationof the filling⚫ As the elbow nozzle blasts right below, filling results in a mound with its apex right below thenozzle. Hence, the nozzle got buried in the filling material before the filling material spread up to
the corners of the cell. Thus blasting became difficult (500 cell). The rail needs to be installed at
a higher location and the distance between the indicator and the nozzle needs to be increased.
The angle of repose at the time was approx. 28°.
⚫ As indicated above, as the filling material gets filled in the shape of a mound in the case of anelbow nozzle, and further since craters are formed due to the blast pressure, bumps are formedin front of the camera. Due to these bumps, it was difficult to verify the filling status on the backside with the camera made available this time.
©International Research Institute for Nuclear DecommissioningNo.253
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (1) Selection of nozzle] Test results ②(Ceiling cell)Rail isburiedCameraCellwall

500 cell / straight

500 cell / straight / camera image⚫ In the case of the straight nozzle, since the steel balls directly hit the cell wall, a large
quantity of steel balls bounce back. As a result, a large quantity of filling material comes outof the target cell from the sides of the rail.
⚫ A cell with 500mm width as well can be filled up to the top portion of the rail.
⚫ In the case of the straight nozzle, since the cell is filled from the back side, it is easier toascertain the status of filling.
©International Research Institute for Nuclear DecommissioningNo.254
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (1) Selection of nozzle] Test results ③ (Ceiling cell)
Estimation #1
Ceiling cell

NozzleVolumeQuantity
Filling timeof fillingminkg

Straight
200

27

126.4

Straight
39

182.5

Straight
51.5

241.0

Straight
63.5
Elbow #3

297.2

Other
kg

Estimated
rate
#2

4.5

1.2

147

16.78

1.2

36.4

3.5

1.0

135

2.86

1.1

39.4

7

1.3

226

35.3

1.2

37.3

6

1.2

219

6.04

1.2

37.5

9

1.3

310

16.7

1.3

36.3

7.5

1.1

280

2.04

1.2

37.6

11

1.3

402

4.98

1.4

37.0

11

1.3

375

2.2

1.3

34.3

6.9

Elbow

500

Filling speed
kg/minActualEstimated Target cell
time
rate
kg
min

5.2

Elbow

400

Quantity of filling

3.6

Elbow

300

Filling time

8.5

#1 Value calculated based on filling rate 60% and filing speed 35kg/min.
#2 Value obtained by dividing the quantity filled in the target cell by the estimated quantity of filling.
#3 Blasting was not possible because the nozzle was buried in steel balls before the indicator got covered.
These are results of the test conducted by setting the position of the nozzle approx. 20mm in the upward
direction.

©International Research Institute for Nuclear DecommissioningNo.255
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (1) Selection of nozzle] Test results ④ (Ceiling cell)⚫ The quantity of filling material required to fill the cell up to the indicator for verifying that the filling heightis completely covered is 1.1 to 1.4 times the estimated quantity. Since dispersion to other cells is less inthe case of elbow nozzle as compared to the straight nozzle, less quantity of filling is needed to fill thecell up to the required height.
⚫ In the case of the 500 cell/elbow nozzle, the nozzle got buried in the filling material before the fillingmaterial spread up to the corners of the cell. Thus blasting became difficult. Hence, if wider cells are to
be used, the cells need to be taller. As a result, the weight of the main body of the access tunnel would
increase.
⚫ In the case of the straight nozzle, since the cell is filled from the back side, it is easier to ascertain thestatus of filling. Meanwhile, it is difficult to ascertain the status on the back side using an elbow nozzle.
Elbow

Straight

Required quantity of filling(Comparison with the target value)

1.1 to 1.3 times

1.2 to 1.4 times

Dispersion to other cells

Small amount

Large amount

Ease of filling (on top of the rail)

Not possible

Possible

Visibility with the camera

Bad

Good

The straight nozzle is selected based on the abovementioned results.
©International Research Institute for Nuclear DecommissioningNo.256
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (1) Selection of nozzle] Test results ⑤ (Wall cell)
Estimation #1
Wall cell

NozzleVolume Quantityof fillingkg

Filling timemin

Straight
No beams

176

823.7

Straight
166

776.9

Straight
165

772.2

Straight
177.5
Elbow

830.7

Other
kg

28

1.2

895.3

88.96

1.1

35.2

25

1.1

897.3

7.04

1.1

36.2

29

1.3

840.3

125.92

1.1

33.3

24

1.1

874.3

13.34

1.1

37.0

28

1.3

831.3

106.72

1.1

33.5

23.5

1.1

825.3

8.84

1.1

35.5

30

1.3

898.3

115.08

1.1

33.8

25

1.1

892.3

22.04

1.1

36.6

22.1

Elbow

Single row

ActualEstimate Target celltime
d ratekg
min

Filling
Estimated speed
kg/min
rate
#2

22.2

Elbow
Parallelrows

Quantity of filling

23.5

Elbow
Zigzag

Filling time

23.7

#1 Value calculated based on filling rate 60% and filing speed 35kg/min.
#2 Value obtained by dividing the quantity filled in the target cell by the estimated quantity of filling.

©International Research Institute for Nuclear DecommissioningNo.257
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (1) Selection of nozzle] Test results ⑥ (Wall cell)⚫ The quantity of filling material required to fill the cell until the indicator for verifying the filling height iscompletely covered is 1.1 times the estimated quantity. The wall cell is 100mm wide which is narrower
than the ceiling cell. Hence it is believed that the indicators at the 4 corners would be covered with asmall quantity of filling.
⚫ The dispersion to other cells is extremely low in the case of elbow nozzle as compared to the straightnozzle (1/5 to 1/10). This large difference is believed to be because the filling time is longer ascompared to the ceiling cell.

⚫ The results pertaining to ease of filling and visibility with a camera were similar to the ceiling cell.
⚫ The status of filling into the vicinity of the reinforcement beams is verified through the window for
verification. It is verified that there has been sufficient filling into the area around the reinforcement
beams. As it is believed that the reinforcement beams have almost no impact, there is enhanced
freedom of design while designing the actual facility.
Elbow

Straight

Required quantity of filling(Comparison with the target value)

1.1 times

1.1 times

Dispersion to other cells

Small amount

Extremely large amount

Ease of filling (on top of the rail)

Not possible

Possible

Visibility with the camera

Bad

Good

Based on the above-mentioned results, the straight nozzle isselected for the wall cell as well.
©International Research Institute for Nuclear DecommissioningNo.258
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (2) Filling method verification test]
Test guidelines: Blasting was carried out at position ① for the duration until the indicators forverifying the filling height were covered, which was verified during Test (1), and thereafter
blasting was carried out at blasting position ②.
Blasting
location②

Partition
Blasting
hose①

Blasting
location

Blasting
hose

400 cell

3100(mm)

500 cell300(mm)①

Zigzagcell

Cell withnobeams

Remarks:
Wall cell: Since the width of all cells is the same (100mm), thecells without beams were tested.
Ceiling cell: As blasting cannot be carried out at position ② inthe case of 500 cell, a 400 cell was tested.
©International Research Institute for Nuclear DecommissioningNo.259
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (2) Filling method verification test] Test results ①
Blasting
location②①

Blasting
hose

Image captured fromabove the cell (28 min)Camera image (28min)

Image captured from above thecell (28 min + 2 min)

3100(mm)Image captured from theblasting location (28 min)

Zigzagcell

Conditions

Cell with
nobeams

Blast pressure: 0.2MPa
Blasting time ① 28 min ② 2 min

The cell has been sufficiently filled up to the top (top of
the nozzle). It was verified that filling is possible by thismethod.
©International Research Institute for Nuclear DecommissioningNo.260
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (2) Filling method verification test] Test results ②①

500 cell

400 cellImage captured from above
the cell (9 min)Camera image (9 min)Image captured fromabove the cell (25.5 min)Camera image (25.5 min)

300(mm)②

Conditions

Partition

Blasting
location

Blasting
hose

Blast pressure: 0.2MPa
Blasting time ① 9 min ② 16.5 min

The cell has been sufficiently filled up to the top (top of thenozzle). Combined with the results of Test (1) on the 500
cell, it is expected that this method of filling can be used in
the case of the 500 cell as well.
©International Research Institute for Nuclear DecommissioningNo.261
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Test (2) Filling method verification test] Test results ③⚫ It was verified that filling is possible up to the top of the rail in a wall cell which has cellheight.
⚫ It is expected that a ceiling 400 cell can be filled up to the top of the rail, and based on the
results of Test (1) on the 500 cell, it is expected that a cell with a width of 500mm can be
filled up to the top of the rail as well.

⚫ With a straight nozzle, since the cell can be filled up to the top of the rail, the required
shielding thickness does not need to be added while setting the height of the rail part.
This is effective in reducing the height of the cell.

Filling up to
the top
Blasting
hose

Required shielding
thickness#=
Cell height# Including some margin©International Research Institute for Nuclear DecommissioningNo.262
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Issues]✓ Structure⚫ Although it is expected that filling material can be filled sequentially from the back side of thecell, as it will not be possible to fill the last cell (assuming it to be outside the R/B) all the way,
measures such as provision of auxiliary cells, filling from the top of the cell, etc. are needed.
⚫ In this test a fiber camera was used to verify filling. In the case of the straight nozzle, a large
number of steel balls bounce back. These steel balls are likely to damage the lens. Hence a lenscover was installed. The cover opened and closed due to the movement of the hinge structure
brought about by pulling the wire. However, an event occurred wherein the filling material got
stuck in the hinge structure and the cover did not be opened or closed. Measures such as
modifying the structure, etc. need to be studied in preparation for installing the actual equipment.
⚫ It was difficult to verify the status of filling on top of the rail with the camera and lights used thistime. Selection of the camera, lights, etc. need to be studied considering application to the actual
equipment.
✓ Shielding performance evaluation method⚫ As the filling rate cannot be determined from the quantity of filling (delivered quantity) because
there is dispersion to other cells, it is difficult to evaluate the shielding performance after fillingthe inside of the cell for each cell. The shielding performance is expected to be evaluated using
the filling rate verified beforehand, but the evaluation including reproducibility of the status offilling, needs to be carried out by the time the method is used in the actual equipment.

©International Research Institute for Nuclear DecommissioningNo.263
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Development Schedule]: Planned: Planned (after revision)*: Actual

FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

FY2022
12

Interim Report
▼

1

2

3

4

5

Interim Report
▼

6

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final report▼

1. Conceptual study
2. Element test plan
3. Test preparation/
Manufacturing oftest equipment
4. Element tests
5. Summary

Remarks* The plan was revised to reflect the progress status of the studies.

©International Research Institute for Nuclear DecommissioningNo.264
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield: Summary➢ In FY2021, the study plan and the preconditions were consolidated and thereafter shielding
was evaluated, for studying the method for additional installation of shield. It was foundthat as the radiation dose from neutron beams is high, neutron shielding needs to beinstalled to reduce the shielding thickness.
➢ Interference with the work of constructing the additional building is expected to be avoided(the access tunnel unit is expected to be pulled over with a crawler crane) by revising therequired shielding thickness from 300mm wall (iron) to 200mm (iron) (part of it added to thecart inside the access tunnel). The method for additional installation of shield continued to
be studied as additional shielding will be installed as required after ascertaining the status
inside the PCV.
➢ It was determined that feasibility of the proposal to additionally install spherical shields
needs to be verified through element tests. The items to be verified, and items to bemonitored, measured and recorded during the filling test were studied, a filling rate of 60%
was planned as the criteria and the test was conducted.
➢ As a result of the element test, it was verified that the spherical shielding material can be
filled up to 20m ahead by using the blast equipment and the straight nozzle. Also, it was
found that filling is possible up to a cell width of 500mm, and that the structures inside thecell (reinforcement material) do not have an impact on filling.
➢ Since spherical shielding material can be filled up to 20m ahead, it was verified that theoperation can be performed from outside the R/B and thus worker exposure can be
reduced.
©International Research Institute for Nuclear DecommissioningNo.265
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
Studies on installation of access equipment, such as the access tunnel method, to be used asaccess equipment for the side access method, have been carried out for further increasing theretrieval scale of fuel debris and reactor internal structures. As the shield plug, etc. (shield plug, block out) in frontof the existing equipment hatch, which is a large and heavy object made of concrete, etc., needs to be removed
before installing access equipment on to the PCV connection part, technology related to safe and efficientdisassembly in confined spaces needs to be studied and developed.
Studies will be conducted on the method and procedures for cutting, disassembling and removing the shield
plug, etc. safely and with certainty in the confined space inside the R/B, transferring the disassembled structuresand storing them in waste containers by remote operation, considering that this work is carried out in a high dose
environment; considering prevention of dust dispersion, removal of structures required for strength such as

intermediate posts, smoothening the cut parts, etc. after removal, and load restriction on the floor inside R/B.
Subsequently, the equipment for cutting, disassembly and removal will be test manufactured, andtheir viability will be verified by element tests using simulated test pieces for confirming feasibility.

©International Research Institute for Nuclear DecommissioningNo.266
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
Table of Contents⚫ Status of studies conducted up to FY2020, issues, implementation details and results⚫ Study procedures (policy)

⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫

Consolidation of pre-conditions
Work of making openings (before the accident) and the removal policy in this project
Study of disassembling procedures
Exposure evaluation
Structure of shield plug
Study of smoothening methods
Purpose of the element tests, test flow
Crane, tools used
Element test results
Summary of test results⚫ Development schedule⚫ Summary©International Research Institute for Nuclear DecommissioningNo.267
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Status of studies conducted up to FY2020]⚫ Rough procedures for the Unit 1 shield plug removal
method were developed, conceptual study and evaluationof the roughly estimated exposure dose were carried out.
[Issues]<Common to Units 1 to 3>⚫ As the shield plug is large and heavy and hence difficult toremove, removal technology needs to be developed.
⚫ Feasibility of the disassembly equipment, etc. considering theload on the floor surface of the building.
⚫ Method of disassembling considering prevention of dust
dispersion under a high dose environment.
⚫ Increase in exposure dose due to increase in the amount ofwork carried out on-site for finely cutting large and heavy
objects.
<Unit 1>
⚫ Method of pulling out the shield plug considering anchoring, etc.
of the drive wheel.
⚫ Method of finely cutting considering the lining material (16mm).

<Units 2, 3>⚫ Method of removing concrete blocks (including intermediate
posts, etc.)⚫ Method of smoothening the floor surface (surface on which the
PCV connection sleeve is installed).

Unit 1(Shield plug)

Units 2, 3(Concrete blocks)(Steel plate + Concrete)(Reinforcement +Concrete)

Illustration of the method of disassembling
Similar examples from overseas
1F-4 X-1B

After removing concrete blocks, the intermediate posts need to be
removed or mortar needs to be shaved off to make the surface smooth.

Illustration of the floor surface of Units 2 and 3©International Research Institute for Nuclear DecommissioningNo.268
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Implementation details]<Common to Units 1 to 3>⚫ Consolidating pre-conditions related to the study.
⚫ Studying the method and procedures for cutting,disassembling, and removing the shield plug, etc. andtransferring the disassembled structures and storingthem into waste containers by remote operation.
Studying the method for preventing dust dispersion,
method for disassembling and transferring considering
the load bearing capacity of the floor (approx. 4.9
ton/m2), etc.
⚫ Test manufacturing the required equipment such as
cutting, disassembly and removal equipment, etc.,
planning and implementing element tests to verify
feasibility of the method for removing the shield plug, etc.

Reinforced concrete
The angle needs to be
removed as it interfereswith the PCV
connection sleeve

After removing the concrete
blocks (1F-4 X-1B)
Comprehensive view of
the Unit 1 shield plug

CounterweightCuttingequipment(horizontal)<Unit 1>
⚫ Study of method of pulling out the shield plug
⚫ Study of equipment for cutting the shield plug by remote
operation⚫ Study of the method of transferring unitized structures(Removal using a cantilever)<Units 2, 3>⚫ Study of remotely operated block-out equipment⚫ Study of method for smoothening the floor surface

Actuatormade of steel

Frame

Cuttingequipment(vertical)

Method of fine cutting[Expected outcome]⚫ Presentation of the method of removing the shield plug, etc.

Method of transferring
unitized structures

Illustration of Unit 1 shield plug removal©International Research Institute for Nuclear DecommissioningNo.269
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Study procedures (policy)]
Disassembly of Unit 1 shield plug
1.
2.
3.

Disassembly of Unit 2, 3 concrete blocks

Consolidation of input, study conditions, environmental conditions of work area
Consolidation of work requirements (functional requirements) and study of action plan
Creation of conceptual diagram illustrating the disassembly work based on the action
planConsolidation of conditions required for substantiation of the study

Evaluation and selection of applicable disassembly tools

Verification of feasibility of the selected disassembly tools (Element tests)

Study of means for smoothening / hatch protection
Development of work steps and identification of issues in each step / worker exposure evaluation

Presentation of action plan in response to the issues and establishment of development plan

©International Research Institute for Nuclear DecommissioningNo.270
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Consolidation of pre-conditions]
In Unit 1 shield is planned to be installed on the northern side of R/B, and in Units 2 and 3 it is planned to be installed on thesouthern side. All shields are to be installed on the equipment hatch, but in Unit 1 it will be on the shield plug, and in Units 2 and 3
it will be on the block wall.
Proposal for installing the access tunnel in Units 1 to 3
As

集

集

電

桝 電

Legend:

FH M

M

照

C

量水器 FP集

Existing
structures

R/B

ダクト

M

パイプ

E

Co

M

桝
集

１/2号機サービス建屋

集
P

集

C

New structures

M

M

As

P

消防水利

M

P

M
C

扉止
Co

桝 桝 M

FP
FH
FH

照

S排水
ポンプ
制御盤

#1_T/B

集
M

M

P
電

#2_T/B#3_T/B集

集

集

コントロール建屋
M#1_R/B

M

Additionalbuilding

MP#2_R/B

R
w/
B

P

電

Rw
/B

P
M

集

Access tunnel

2号機原子炉建屋

2号機廃棄物処理建屋

Access tunnel

FH

FP
H.H

Additionalbuilding

Rw/B#3_R/B
Rw/B
Access tunnel

M
扉止P
FSTR建屋(1,2機)

LP-G屋外中継盤

M

H.H

Exhaust
stack
TEL

M

H.H
警備詰め所

Exhauststack

M集

消火設備小屋

M

集

集

雨集

油分離層

扉止

FH

Co

沈殿層

M
M

桝
扉止
集

集

扉止

TEL

照

集

桝
M

桝
桝
集

送水口

As
FP

Co

FH

H.H

１/２号機
セメントブロアー室

M
集P

カードリーダ盤

FP

地中電線路
連絡送水口
集

E

桝
M

M

M

M

門扉
M

Unit 1: Shield plug

M

M

M

Units 2, 3: Concrete blocks(Image)©International Research Institute for Nuclear DecommissioningNo.271
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Consolidation of pre-conditions (Unit 3)]➢ Objects to be removed (Concrete blocks) #1➢ Environmental conditions #1
Items

Concrete blocks (Enlarged view)

Specifications

Liner plate (Outside the scope of removal#2)
TargetIntermediate support for the wall
External dimensions(Intermediate posts)
Mass
Partitioning
steel plate

Mortar(Filling thegaps)

Composition2885

Air dose rate
Floor load bearing
capacity
Carrying-in/out
Height at which workis carried out

Reinforcement

Unit 3 Concrete blocks
W 3510 × D 1600 × H 2885 (mm)Approx. 36 ton
Concrete blocks + band plate + wire torus+ intermediate support for the wall, mortar finishing of gaps
Approx. 18 mSv/hApprox. 4.9 ton/m2
Western side of R/B (Truck bay door (W4900 × H4900mm))
Approx. 4m or less

3510

1600

Truck bay door

Air dose rate on the southwestern side (work area) of the R/B first floor in Unit 3

Foundation bolts

Band plates,
wire torus

Numbers indicate air doserate(mSv/h)Concrete blocks

BSW
0.12

Concrete blocks
0.70#1: The structures and dimensions include those from drawings from other units thatwere used as reference and hence include estimates as well.
#2: As it gets embedded into BSW: Data collection period: April 1, 2020 to March 31, 2021
: Measured on November 24, 2021
©International Research Institute for Nuclear DecommissioningNo.272
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Work of making openings (before the accident) and the removal policy in this project]
Items

Content in the red frame: Items toundergo the mock-up test this time
Unit 2, 3 Concrete blocks

Unit 1: Shield plug

Mainly entire blocks of concrete that normally travel over the

Blocks are stacked like bricks and some of the gaps are filledrail on electricity.

with mortar.

⚫
⚫

①

Overview of the target

Main procedures(Prior to the accident#)# Prior to the accident at
the Fukushima Daiichi
Nuclear Power Station
associated with the Great
East Japan Earthquakethat occurred on March
11, 2011.

⚫

(Measure 1) Pulling out by moving with the help of electricity.
(Measure 2) Pulling out by rotating the shaft (external drive
shaft) connected to a motor, etc. The external drive shaft is
powered, has breaks and clutch (being verified), and a wheel
clamp (being verified).
(Measure 3) Pulling using a winch, etc.

It should be confirmed whether or not the external drive shaft can beused. If it can be used, the shield plug should be pulled out using theexternal drive shaft. If it cannot be used, it should be pulled out using awinch.
Removal policy in this PJ(Note)
・Before pulling, it should be made sure that there is no foreign material(including the rail cover) on the rail.
・Rust should be removed from the rail to the extent possible.
・It should be assumed that electricity cannot be used.

②③④

Shaving off the upper mortar using a breaker. (The mortar
between the BSW and the block is shaved off as needed)
Removing the block while making sure it does not getdamaged.
Removing the intermediate support.
Removing the L shaped steel at the top and bottom.

It should mainly be disassembled using a breaker.
(Note)
・Prior to the accident, since the blocks (approx. 800 blocks) were reused, they were removed carefully to ensure there is no damage, but
this time they do not need to be restored.
・Cutting with the help of wire saw, etc. was considered, but it wasdetermined that using a wire saw would be difficult because of thedepth.

©International Research Institute for Nuclear DecommissioningNo.273
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Study of disassembly method (Unit 3)] Study of disassembly procedures (1/2)
1. Work of carrying-in the equipment

2. Disassembly of concrete blocks from the front side

Concrete blocks

Ventilation system
Work room

3. Collection of concrete blocks
Ventilation system

Concrete blocks

Concrete blocks

Work room

Breaker

Door

Door
Crane

Crane

Truck bay door
Remotely operated
temporary shield

Illustration of
temporary building

Receptacle fordisassembled pieces

Truck bay door
Front (depth approx. 800mm)

Additional information: Interfering objects are removed, temporary building
set up is completed

Additional information: Intermediate posts are cut with the cutting equipment. The
disassembled pieces are collected using a bucket and a lifting magnet. While disassembling
concrete blocks, the mortar joints are shaved so that the size of the disassembled pieces is
as large as possible.

4. Installation of preventing member

5. Disassembly of concrete blocks from the back side

Ventilation system

Concrete blocks
Preventing
memberWork room

Illustration of
temporary building

Transportation
cart

Additional information: If collecting with the bucket is possible, collection isdone using the grabbing equipment

6. Removal of reinforcement (front, middle, back)Concrete blocks
Back (depth approx. 800mm)

Ventilation system: Site to be cut
Cuttingequipment

Work room

Remotely operated
temporary shield

Wall intermediate support
Reinforcement(front)Preventing
memberPreventing
member

Door

Door
Crane
Truck bay door
Illustration of
temporary building

Transportation
cart
Remotely operated
temporary shield

Additional information: Being planned for preventing debris fromfalling inside the equipment hatch

Truck bay door
Illustration of
temporary building

Transportation
cart

Crane

Remotely operated
temporary shield

Additional information: Implemented in the same manner as No.
2 and 3

Preventing member
Receptacle for
Reinforcement Reinforcement Reinforcement
disassembled(Front)(Back)(Middle)piecesAdditional information: Disassembled and removed in the order ofReinforcement (front) ⇒ Partitioning steel plates ⇒ Reinforcement (middle)⇒ Partitioning steel plates ⇒ Reinforcement (back)Preventing member: Planned to be installed by opening a through hole into the block by means of core boring, etc. The purpose of installing it is to prevent disassembled pieces from falling in between the PCV
and BSW and preventing the equipment hatch from getting damaged, but its necessity needs to be discussed further.

©International Research Institute for Nuclear DecommissioningNo.274
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Study of disassembly method (Unit 3)] Study of disassembly procedures (2/2)
8. Removal of foundation bolts (ceiling)

7. Removal of partitioning steel plates

9. Removal of foundation bolts (floor): Site to be cut
Wall intermediate support
Partitioning steel plate
Circular saw
cutting equipment

Receptacle fordisassembled pieces

Preventing member
Preventing
memberFoundation bolt
Circular saw
cutting equipment

Foundation bolt
Preventing
memberPreventing
memberPreventing
memberFoundation bolts (ceiling)

Partitioning steel plate

Additional information: Reinforcement (ceiling) can be removed along withthe removal of foundation bolts (ceiling)

10. Pouring of mortar

11. Smoothening

Additional information:Foundation bolts (floor) and reinforcement (floor) canbe removed by shaving the floor surface or with the help of a polisher.

12. Clearing

Filled with mortar, etc.

Filled with mortar, etc.

Preventing
memberFoundation bolts (floor)

Additional information: Disassembled and removed in the order ofReinforcement (front) ⇒ Partitioning steel plates ⇒ Reinforcement (middle)⇒ Partitioning steel plates ⇒ Reinforcement (back)Filler material
Injection equipment

Image illustrating the
excavation for removing
foundation bolts

Breaker

Ventilation system

Preventing
memberTraces of disassembling BSW (floor)

Cart

Preventing
memberPreventing
memberFiller material

Additional information: In this step, filler material such as self levelingmaterial, etc. is injected depending on the status of the floor surface.

Door
Traces of disassembling BSW (floor)
Truck bay door

Filler material

Additional information: If smoothening has not been achieved in No. 10, thefiller material is polished using a polisher.

Remotely operated
temporary shield

Illustration of
temporary building
Additional information: Removing the equipment and moving the remotely
operated temporary shieldNote) The status (dose / condition) of the target object is verified at every work step (1 to 12), and then work is continued.

©International Research Institute for Nuclear DecommissioningNo.275

6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]④ Disassembly of shield plug
[Exposure evaluation (Unit 3)]
Disassembling
procedures
No.

Assumed human work

1

Carrying-in and assembling the ventilation equipment and work room,
carrying-in the remotely operated temporary shield2

Total time required
for work

Environmental
radiation dose

Exposure dose(hr)(mSv/h)(mSv/person)

21

11 to 18350

4 to 51462

Replacing the processing and finishing tools (Breaker, cutting
equipment)

11

0.12

1.32

2

2.64

3

Replacing the processing and finishing tools (Bucket, grabbing
equipment)

12

0.12

1.44

2

2.88

4

Replacing the processing and finishing tools (Equipment for making
holes, grabbing equipment)

2

0.12

0.24

2

0.48

5

Replacing the processing and finishing tools (Breaker, cutting
equipment,
bucket, grabbing equipment)

20

0.12

2.4

2

4.8

6

Replacing the processing and finishing tools (Cutting equipment)

3

0.12

0.36

2

0.72

7

Replacing the processing and finishing tools (Circular saw cutting
equipment,
grabbing equipment), replacing the disc when it becomes blunt

7

0.12

0.84

2

1.68

8

Replacing the processing and finishing tools (Circular saw cutting
equipment)

1

0.12

0.12

2

0.24

9

Replacing the processing and finishing tools (Breaker, grabbing
equipment)

2

0.12

0.24

2

0.48

10

Replacing the processing and finishing tools (Breaker, grabbing
equipment)

2

0.12

0.24

2

0.48

11

Replacing the processing and finishing tools (Smoothening tool)

1

0.12

0.12

2

0.24

12

Replacing the processing and finishing tools (Grabbing equipment,
cutting equipment)

2

0.12

0.24

2

0.48

Work place

Inside R/B

Temporary building

Exposure dose
No. of persons
(mSv)

Total

1477.12Note) Since the dose rate inside the R/B is high, the overall exposure dose increases → If the exposure dose does not reduce even after
decontamination, shield needs to be installed at a location such that it does not interfere with removal work.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (1) Development of the Method for Installing
Access Equipment]④ Disassembly of shield plug
[Structure of shield plug]

No.276The structure of the Unit 3 shield plug is shown.
As mentioned in the previous pages, in Unit 1 unitized concrete blocks are pulled out with the help of electricity.
And, in Units 2 and 3, a large number of concrete blocks are piled. Further amongst these units, since there areintermediate posts made of steel in the middle of the shield plug in Unit 3, it is believed that disassembly and removal
are more difficult in Unit 3 as compared to Unit 2. Hence it was determined that disassembly and removal of the Unit
3 shield plug would be undertaken during the MU test this time.
ConcreteblocksIntermediate posts

MortarIntermediate post

MortarConcrete

BSW floor

1000
600

1600

1000

Scope of thesimulated test piece

Unit 3 concrete blocks

250
0

250
0

Test piece©International Research Institute for Nuclear DecommissioningNo.277
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Study of smoothening methods]
After removing the concrete blocks, the PCV connection sleeve is installed on the floor surface which becomes the load bearing point
for the access tunnel. Also, the wall surface becomes the measurement point for 3D scanning for installing the PCV connection sleeve.
Therefore, the methods for smoothening (#1) the floor surface and the wall surface were studied.
(#1: Smoothening: To level and create a flat surface)
Study flow of smoothening methods
Study of smoothening methods
Concrete blocks

Smoothening test

The method that is feasible andprovides higher smoothness isselected from multiple proposals
and tested.

Measurement ofsmoothness

Multiple tests are conducted, andsmoothness (flatness and level)is measured.

Selection ofsmoothening method

Based on the results of themeasurement carried out during
the test, the method that provides
good smoothness is selected.

Reflection into the PCV Reflected into the design andconnection sleeve design structure as a condition for remote
installation of PCV connection
and structure

Before removing concrete
blocks

PCV connection sleeve

After removing concrete blocks(Installation of PCV connection
sleeve completed)

The existing concrete blocks need to be removed for
installing the PCV connection sleeve.

sleeve©International Research Institute for Nuclear DecommissioningNo.278
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Purpose of the element tests]
The element test has the following two purposes: ① Disassembling and removing the shield plug (including smoothening of the wall surface) and ② Smoothening the floor surface after
disassembling and removing the shield plug. The test items are indicated below.
① Disassembly and removal of shield plug
The test items are indicated in the table below. It is believed that concrete can be removed by common methods. In this test, since the extent of adhesion of mortar to the intermediate posts and thesmoothening# of the adhered mortar will be verified, it was decided that the mortar wall should be simulated rather than concrete blocks. Further, the floor surface has been simulated as a concrete surface.
# Removing the mortar that has adhered to the wall surface of the opening that serves as reference while installing the PCV connection sleeve. In this test, the wall surface is replaced by intermediate posts.
Processing andfinishing tools

Test Item(To be processed)

Removal of concrete blocks(During the test mortar was
simulated instead of concrete
blocks in order to verify adhesionof mortar to the metal surface.)

Breaker

Verification contents

Criteria (Measurement and confirmation items)① Verifying whether or not it is possible to smoothen the mortar stuck on
the lining plate

The mortar should not be significantly adhered on to the wall surface. (Heightat which it is adhered)② Verifying the impact when the breaker collides with the partitioning steel
plates or reinforcement

There should not be any significant deformation. (Condition ofdamage/deformation)③ Verifying whether concrete is shaved to an extent that it does not comein contact with the floor rebars (Thickness of concrete cover approx.
40mm)

・Should not come in contact with the rebars.
・There should not be any significant deformation.

Intermediate posts(L100 x 100 x 7)

Guzzilla cutter
Breaker

Verifying the status after cutting with the Guzzilla cutter and shaving withthe breaker. (It is believed that shaving is possible, but it is performed
considering method selection.)

There should not be any remnants (L type beam) and shaving should bepossible. (Maximum depth, maximum width)

Foundation bolts

BreakerChecking the status after shaving#. It is believed that shaving is possible,
but it is performed considering method selection.

There should not be any remnants (foundation bolts) and shaving should bepossible. (Maximum depth, maximum width)② Smoothening of the floor surface after disassembling and removing the shield plug
Test Item

Finishing method

Verification contents

Laying self leveling material

Laying self leveling material on the test piece (floor surface) that is shaved
with a breaker, and checking for gradient, etc. after laying.

・Floor surface gradient・Unevenness of floor surface

Laying non-shrink mortar

Laying non-shrink mortar on the test piece (floor surface) that is shaved witha breaker, and checking for gradient, etc. after laying.

・Floor surface gradient・Unevenness of floor surface

Polishing with the help of a polisher

Polishing on top of test piece shaved up to the floor surface, using a polisher.

・Unevenness of floor surface
・Amount of polishing of anchor bolt

Shaving of floor
surface

Floor surface
polishingCriteria (Measurement and confirmation items)©International Research Institute for Nuclear DecommissioningNo.279
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Test flow]

Disassembly and removalof concrete blocks (mortar
part)

・Mortar is removed under various conditions, and theattachment is selected.

Removal of mortar adhered
to the intermediate posts

・ The extent of adhesion of mortar is verified.
・ The adhered mortar is removed, and the attachment isselected.

Test No. 1

Cutting of intermediate
posts

Test No. 2

Removal ofanchor bolts

Test No. 3
Cutting of bolts
using a crane

Test No. 4

Filling of filling material
Smoothening of filledsurface・ The anchor bolts are removed (manned, grinder)

Cutting with agrinder (manned)

Removal of remains of theintermediate posts

Floor surface isshavedTest No. 6

・ The intermediate posts are cut, and the cutting
method is determined.

・ After removing the anchor bolts, the remains of theintermediate posts are removed.

Removal ofanchor bolts

・ After removing the remains of the intermediate posts, theremains of the anchor bolt are removed.
In order to install the PCV connection sleeve, the anchor bolts
Floor surface not shaved are removed to an extent that they are at the same level or lower
than the existing floor surface.
Removal of anchor bolts
with a polisher

Test No. 5©International Research Institute for Nuclear DecommissioningNo.280
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Crane used]
Test at actual facility, MU Test

Stand-by

3 ton class

8 ton class

Photograph
Dimensions
Specifications
Use
applications

HitachiConstruction
Machinery Co.,Ltd.
ZAXS75US-5B
Short reachspecifications

HitachiConstruction
Machinery Co.,Ltd.
ZAXIS30U-5B
Short reachspecifications

W 1650 x D 4050 x H 2540 (mm)W 2320 x D 4820 x H 2820 (mm)Equipment mass: 3840kg

Equipment mass: 7430kg

Mountable attachment mass: 450kg

Mountable attachment mass: 1430kg

Maximum height at which work is carried out: 4240mm

Maximum height at which work is carried out: 5590mm

Average ground contact weight: 3.0ton/m2

Average ground contact weight: 3.8 ton/m2

Disassembly and removal of concrete blocks, band plate,wire torus, mortar
Disassembly and removal of intermediate support for thewallSame as described on the left.
Arranged as stand-by in case disassembly and removal cannot
be accomplished with the 3 ton class.

©International Research Institute for Nuclear DecommissioningNo.281
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Tools used]
Details about the attachments installed at the tip of the crane are indicated below.
Use applications

To beprocessed/handled

Rough specifications (general)

Breaker(Moil point)

For crushing concrete

Concrete blocks, BSW(Floor)Concrete, bedrock, hard floor, road work

2

Breaker(Flat end)

For crushing concrete

Concrete blocks, BSW(Floor)Concrete, bedrock, hard floor, road work3

BucketFor collecting pieces,
etc. of concrete

All disassembled pieces

Capacity (m3): 0.11

4Large concrete
crusher(Guzzilla cutter)

For cutting/ grabbing
and collecting steel
platesWire torus, reinforcement(L100 x 100 x 7mm),
partitioning steel plate(6mm)

Target: Iron frame, reinforced concrete

No.

Attachment

1

Figure©International Research Institute for Nuclear DecommissioningNo.282
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Smoothening materials / tools]
Details about the materials and tools used for smoothening are indicated below.

No.

1

Tool

Self levelingmaterial

FigureUse applications

For smoothening
BSW (floor)

To beprocessed/handled

Rough specifications

BSW (floor)

Has better fluidity as compared to nonshrink mortar, but is not as strong. (Canbear the load of the PCV connection
sleeve and AT)
The surface on which the material is tobe placed needs to be coated with aprimer before placement.

2

Non-shrink mortar

For smoothening
BSW (floor)

BSW (floor)

Fluidity is not as good as the selfleveling material, but strength is better.
The surface on which the material is tobe placed needs to be moistened withwater before placement.

3

PolisherFor smoothening
BSW (floor)

BSW (floor)

Ordinary concrete

4

Breaker(Flat end)

For crushing concrete

Concrete blocks, BSW(Floor)Concrete, bedrock, hard floor, road work

©International Research Institute for Nuclear DecommissioningNo.283
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Element test results Test No. 1-1 to 1-4]

Division of the test piece

The results of tests on disassembly and removal of shield plug are indicated.
The shield plug portion of the test piece is divided into 4 parts (Part A to Part D). Disassembly and removal, wall surface smoothening, and collection ofdisassembled pieces was carried out using different cranes and attchments on each of these parts respectively.
No.

1-1

1-2

1-3

1-4

To be processed

Shield plug Part A(Mortar)Shield plug Part C(Mortar)Shield plug Part B(Mortar)Shield plug Part D(Mortar)

Crane

Work

Attachment

Disassembly and removal

Breaker (Moil point)

Wall surface smoothening－

3 ton class crane

3 ton class crane

3 ton class crane

8 ton class craneCollection of disassembled pieces

BucketDisassembly and removal

Breaker (Moil point)

Wall surface smoothening

BucketCollection of disassembled pieces

BucketDisassembly and removal

Large concrete crusher

Wall surface smoothening

BucketCollection of disassembled pieces

BucketDisassembly and removal

Breaker (Moil point)

Wall surface smoothening

BucketCollection of disassembled pieces

Bucket (3 ton crane)

Results

Remarks

Can be disassembled and removed.
Disassembled pieces of a certain size can be collected,
but disassembled pieces in powdered form cannot becollected with a bucket. (Same for No. 1-2 to 1-4)

Mortar of length 5cm x width 1cm
x height 1cm remains

Can be disassembled and removed.
The mortar got peeled off fromthe intermediate posts and thefloor surface.
Disassembly is possible to a certain extent, but complete
disassembly and removal is not possible as the blade
does not get lodged.

Can be disassembled and removed.
Smoothing can be accomplished using a bucket.

The mortar got peeled off fromthe intermediate posts and thefloor surface.

As the intermediate posts have anti-rust coating, mortar did not adhere. Also, it is believed that mortar did not adhere since laitance treatment of the floor
surface was not carried out at the time of mortar jointing. (With regards to Laitance # treatment, excavation was not carried out on the underside of the shieldplug to see the smoothening of the floor surface.)#Laitence treatment: The treatment of removing the thin layer accumulated on the surface at the time of mortar jointing.
In some cases the mortar got peeled off from the intermediate posts and the floor surface, but disassembly and removal were possible even when the mortar did not get peeled off.
In the actual equipment as well, the area on which mortar is adhered is expected to be small, either because the surfaces are made of metal (wall surface) or because mortar has not adhered.
Also, it was verified that smoothening can be achieved using a bucket even if mortar is adhered. (Test results are indicated on the following pages.)©International Research Institute for Nuclear DecommissioningNo.284
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Element test results Test No. 1-4]
No.

1-4

To be processed

Shield plug Part D(Mortar)Crane

8 ton class craneWork

Attachment

Disassemblingand removal

Breaker (Moil point)

Wall surface
smoothening

BucketCollection ofdisassembled
piecesBucket (3 ton crane)

Results

Remarks

Can be disassembled and removed.
Smoothing can be accomplishedusing a bucket.

The mortar got peeled offfrom the intermediate posts
and the floor surface.

Part D

Mortar was peeled offfrom the concrete blocks
and wall part as a single
unit

8 ton craneMortar removal using abucketWhiledisassembling

Remains only on
the floor surface
Mortar adhered to theintermediate posts

Top portion of thetest piece

After completing
disassembly of the sideof the test piece

Mortar removal completed©International Research Institute for Nuclear DecommissioningNo.285
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Element test results Test No. 5 Floor surface smoothening]
It was verified whether the anchor bolts can be cut using only the polisher without shaving the floor surface.
No.

Height of the bolts
from the floor surface

To be processed

CutterResults

5-1

1mm

Can be cut

5-2

2mm

Can be cut

5-3

3mm
Anchor bolts

Can be cut
Polisher

5-44mm

Criteria

Remarks

The height of theanchor bolts should
become the same asthat of the floor surface

Cannot be cut

As smoothening took time, thefloor surface around the bolt got
shaved.
However, if it takes time, cutting
itself becomes possible.

Polisher specifications
・ Linax KLX-38
・ Mass approx. 100kg
・ 200V

Dust collector

・ Used for grinding orroughening concrete, mortar.

Before processing No. 5-4

Dust collection box

Blade

Compete view of polisher

Smoothening work using apolisher

Polisher (blade surface)
After processing No. 5-4

It was verified that the bolts that are 3mm or less from the floor surface can be cut using the polisher.

©International Research Institute for Nuclear DecommissioningNo.286
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Element test results Test No. 6 Floor surface smoothening]
The floor surface was shaved using a breaker in preparation for filling filling material for smoothening, and the shaved surface was filledwith filling material. Results of smoothening are indicated on the following page.

No.

To be smoothened

Crane

Work

Filling material

5-1Concrete floor surface (Approx. 900mm x 900mm x
Depth 40mm)

3 ton class
Crane

Shaving offloor
surface

Self leveling material

5-2Concrete floor surface (Approx. 1200mm x 600mm x
Depth 40mm)

3 ton class
Crane

Shaving offloor
surfaceNon-shrink mortar

Before shaving thefloor surface

After shaving thefloor surface(Before removing
the disassembled
piece)

After shaving thefloor surface(After removing thedisassembled
pieces)

While filling non-shrink
mortar

Filling completed(Right after filling)

Filling completed(After 1 week of drying)©International Research Institute for Nuclear DecommissioningNo.287
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Element test results Test No. 6 Floor surface smoothening]
The test piece was measured with the 300mm pitch (81 points). It was measured 3 times in all. The intersection points shown in the figure below are the measurement points. After fillingthe filling material, measurement was carried out after providing 1 week of drying period. Thereafter, the area that was filled with filling material was polished with a polisher, and after
ensuring that the area appeared to be smooth, measurement was carried out.

i-3.1 -2.8 -2.5 -3.1 -3.3 -4.1 -4.3 -1.7 -4.1

i-1.6 -1.2 -0.7 -1.2 -1.5 -1.8 -2.0

0.8 -1.6

h

-2.3

2.1

2.3 -0.2 -1.9 -3.0

-1.0

3.5

3.7

1.1 -1.3 -1.9 -0.7

2.8 -0.3

g

-2.5

2.4

3.4

f

-2.2

2.2

e

-0.5

3.1

i

h

Area filledwithnon-shrink
mortargfe
After smoothening using a polisherdArea filled withself levelingmaterialcReference
point

Status of measurement

Self-check
Self levelingmaterial

Non-shrink
mortarAveragevalue+5.7mm-1.3mmMaximum+6.1mm+3.6mm

-0.9

3.8

1.9 -1.8

0.4 -2.4

0.2 -0.6

3.2 -1.0

g

-1.4

3.5

4.6

1.3 -1.6

0.4

0.0

3.5

4.7

0.3 -2.5

0.0

3.6

3.5 -1.7

f

-1.2

3.2

5.8

1.0 -3.1

0.8

3.1

4.3 -0.3

5.1

4.7

2.2

4.4

4.8 -1.1

e

0.3

3.8

4.3

0.4

0.9

2.2

5.2

6.1

0.3

5.9 -0.7

d

-0.3

3.9

3.0

1.1

2.0

2.2

6.5

7.1

0.4

-1.0

2.3

3.2

2.2

1.6

1.3

3.9

5.8

0.3

6.0

5.8

5.4
5.7

1.5

5.6

0.6

c

-1.4

4.1

6.1

6.0

5.6

0.9

3.0

4.8 -0.9

c

b

b

-0.7

2.4

6.1

6.0

5.7

2.9

2.9

2.9 -0.8

b

-0.5

1.5

0.8

0.6

0.7

2.9

3.8

3.9

0.2

a

a

0.0

1.2

2.5

2.0

2.5

1.6

1.6

3.3 -0.5

a

0.0

1.3

2.7

2.2

2.8

1.9

2.1

3.9

0.1

1

2

3

4

5

6

7

8

1

2

3

4

5

6

7

8

9

1 2 3 4 5 6 7 8 9After smoothening using a polisher(Lateral surface)

Only filling material
Filling
material

d

2.7

h

Minimum+4.7mm-4.3mm9

Results of measurement before smoothening

Results of measurement after smoothening

Filling material + Polisher

Maximum Minimum+1.4mm+7.9mmAveragevalue+1.7mm-0.8mmMaximum+4.3mm+3.1mmMinimum+0.7mm-3.1mmMaximum Minimum

Results+3.6mm・There is little variation in the case of only filling material. (Uniformly spread)・When the polisher is used to smoothen the filling material and the edges of theexisting floor surface, the existing floor surface gets polished as well.
⇒ A smoother surface is expected to be achieved, if there is a mechanism toadjust the polishing height of the polisher.

+6.2mm・The filled surface is uneven before as well as after polishing with the polisher
and hence the measurement results are varied.
(Not uniformly spread)・Similar to the self leveling material, issues at the time of polishing the edges arepresent in this case as well.

The self leveling material that spreads uniformly and has a smoothening effect even before polishing with the help of a polisher, is expected to be used.
Also, it is expected that further smoothening effect can be achieved by providing the polisher with a height adjustment feature.
For reflection into the structure of the PCV connection sleeve, 3D measurement is carried out before installation to ascertain the shape of the floor
surface and adjust the shim, etc.
©International Research Institute for Nuclear DecommissioningNo.288

2. Development of the method of installing access equipment
2. 3 Disassembly of shield plug
[Summary of test results]
Test No. 1: Disassembly and removal of concrete blocks (mortar)
・ Removal of concrete blocks (mortar) is expected to be possible by combining the methods tested
this time.
⇒ Disassembly with 3 ton class crane + breaker will be primarily considered.
・ Mortar and metal did not adhere even as much as was expected.
⇒ As it was possible to remove the sites to which mortar adhered using the bucket, even if theextent of adhesion is larger in the actual equipment, it is believed that the mortar can beremoved.
・ With regards to adhesion of mortar and concrete, the extent of adhesion changed depending onwhether laitance treatment was carried out.
⇒ Smoothening will be carried out using the polisher depending on the extent of adhesion ofmortar. If mortar has not adhered and the surface is smooth, polishing is not required.

・ Large blocks of disassembled mortar pieces can be collected using the bucket, which is the tool
made available during this test.
⇒ Disassembled pieces that are small or in powder form will be collected by means of suction.
©International Research Institute for Nuclear DecommissioningNo.289

2. Development of the method of installing access equipment
2. 3 Disassembly of shield plug
[Summary of test results]
Test No. 2: Disassembly and removal of intermediate posts
・ Intermediate posts can be cut using a large concrete crusher either by means of the horizontal
cutting method or the triangular cutting method.
⇒ Since the triangular cutting method offers better cutting efficiency, the triangular cutting
method will be primarily considered. However, while cutting the upper portion of theintermediate posts, sites where the triangular cutting method cannot be used are expected toarise from the perspective of the access range and the position of the crane. In such cases,
the horizontal cutting method will be used in combination.

・ It was difficult to cut the L steel parts of 6mm thickness installed in front, in the middle, andbehind the intermediate posts, but upon repeated cutting, the welded portion of the L steel part
broke, and was possible to be disassembled and removed.
⇒ The welded portion of the L steel is assumed to be pitch welded, but the welding method in
the actual equipment is unknown. An attachment with a larger output than the current
attachment needs to be arranged for.
・ It was possible to collect large disassembled pieces (L steel, etc.) resulting from the cutting
using the bucket, but the smaller disassembled pieces (metal about several cm large) were
impossible to be collected.
⇒ Lifting magnets, etc. may be used for collecting small disassembled pieces.
©International Research Institute for Nuclear DecommissioningNo.290

2. Development of the method of installing access equipment
2. 3 Disassembly of shield plug
[Summary of test results]
Test No. 3: Cutting of anchor bolts
・ A grinder or a chip saw is being considered for cutting the anchor bolts, but a breaker or a large
concrete crusher was able to be used as well.
⇒ If a grinder or a chip saw is used, measures against fire should be taken.

Test No. 4: Removal of remains of the intermediate posts
・ It was verified that for the bottom part of the intermediate posts the anchor bolts can be cut andcan be grabbed and removed by means of the large concrete crusher.
Test No. 5: Smoothening of floor surface and cutting of anchor bolts
・ The remaining parts of the anchor bolts that are 3mm or less can be cut using a polisher.
⇒ A generic polisher was used in this test, but it may be possible to increase the allowance forheight of the remaining parts by changing the blade.

©International Research Institute for Nuclear DecommissioningNo.291

2. Development of the method of installing access equipment
2. 3 Disassembly of shield plug
[Summary of test results]
Test No. 6: Floor surface smoothening
・ It is expected that the floor surface can be smoothened by combining the self leveling material
and the polisher.
⇒ The non-shrink mortar is highly viscous and work involving it requires practice. Hence it is notsuitable for remote operation. Also, if floor surface mortar can be easily peeled off and hence
does not require much shaving work, it is believed that smoothening can be achieved with only
the polisher.
⇒ This time a generic polisher was used for the test. Hence there was no control at locations ata height. In the actual equipment, the height of the surface being polished by the polisher will
be controlled by means of tools, etc.

Further, after smoothening the floor surface, the gradient or unevenness of the floor surface isplanned to be measured by means of 3D scanning, and the results are planned to be reflected while
making prior adjustments to the seating surface of the PCV connection sleeve. (Example of themethod of adjustment: Installing a shim, etc. at the bottom surface of the PCV connection sleeve)©International Research Institute for Nuclear DecommissioningNo.292
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Development Schedule]: Planned: Planned (after revision)*: Actual

FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

FY2022
12

Interim Report
▼

1

2

3

4

5

Interim Report
▼

6

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final
report
▼1. Conceptual study
2. Element test plan
3. Test preparation /Testmanufacturing oftest equipment
4. Element tests
5. Summary

Remarks* The plan was revised to reflect the progress status of the studies.

©International Research Institute for Nuclear DecommissioningNo.293
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
➢The course of study and preconditions pertaining to the method ofdisassembling the shield plug in Unit 1 and concrete blocks in Units 2, 3 wereconsolidated in FY2021, and the disassembly and removal procedures werestudied briefly. The disassembly procedures were consolidated. Issues in themethods were identified and a rough exposure dose evaluation was carriedout.
➢The cranes and tools to be used were substantiated, and whether or not theitems to be processed such as concrete blocks, etc. can be processed wasstudied. The necessity of the test including the study of smoothening methods
was evaluated, and the test plan was formulated (test items, verification
contents and judgment criteria were consolidated).
➢Element tests were conducted based on the above-mentioned test plan, and it
was thus anticipated that it will be possible to remove concrete blocks in Unit
3 by combining the methods tested this time (3 ton class crane + breaker).
Also, issues in application to the actual equipment were identified from thetest results and consolidated.

©International Research Institute for Nuclear DecommissioningNo.294

6. Implementation Items of This Project1) Development of side access method(2) Development of Disassembling and Removal Technology① HVH disassembly
Development is being carried out concerning disassembly, removal, etc. ofinterfering objects for further increasing the scale of retrieval of fuel debris andreactor internal structures. Technology for verifying the feasibility of the work of
cutting pipes, installing utilities (hose, etc.), etc. which is carried out outside thepedestal inside the PCV using equipment for remote operation, was developed sofar.
This development will enhance fuel debris retrieval throughout by securing awork area by removing large HVH from among the equipment installed outside thepedestal, as also will enhance the work efficiency of removing fuel debris anddeposits from the basement floor of the pedestal. Also, as heavy motor (several
hundred kilos) is placed on top of the HVH, technology for disassembling while
ensuring it does not fall, is required. Upon studying and consolidating therequirements for disassembling and removing HVH, considering the impact of
obstacles such as grating and other equipment, etc. present outside the pedestal,element tests on disassembly and removal by means of remote disassembly
equipment developed so far will be planned and implemented using simulated
test pieces considering remote operation in limited space, and the feasibility of
specific cutting/collection methods will be verified.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]

No.295① HVH disassembly
Table of Contents⚫ Development results related to the side access method achieved so far andcorrelation with this project⚫ Issues, implementation details and results⚫ Main specifications of the HVH disassembly robot⚫ Robots and equipment associated with the work of disassembling andremoving the HVH⚫ Blades associated with the work of disassembling and removing the HVH⚫ Scope of simulation in the element tests associated with the work ofdisassembling and removing the HVH⚫ Contents to be verified during the element tests⚫ Element test results⚫ Issues⚫ Development schedule⚫ Summary©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly andRemoval Technology]

No.296① HVH disassembly
Development results related to the side access method achieved so far and correlation with this project are
Pedestal opening
indicated below.
Flexible task arm# Opening through which
Fundamental technology upgrade (Implemented in FY2017-18)

equipment can be carried in
About 700mm opening

Positioning
arm
移動アーム

[Verification of feasibility of the fundamental work of cutting, collecting, etc.]➢
Method of removing interfering objects from the basement floor inside
PCV (outside the pedestal)➢
Method of removing interfering objects from inside the pedestal(Assembly type beam method)➢
Method for preventing spread of contamination to the S/C (Method ofsetting up dikes was selected)

Assembly typebeam

Task arm
作業アーム
Flexible taskarmFurther Increasing the Scale of Retrieval (Implemented in FY2019-20)[Study of response measures based on the issues]➢
Method of constructing the utility line inside PCV➢
Method of removing interfering objects from inside the pedestal (Small
equipment method)➢
Method of setting up dikes for preventing spread of contamination(Formwork and partition carrying-in method)

Implemented in this project[Verification of feasibility looking ahead at the actual equipment]➢
Disassembly of large interfering objects (HVH) outside thepedestal➢
Disassembly of large interfering objects (HVH) inside thepedestal (CRD changer)➢
Method of removing interfering objects from inside the pump pit

CRD
opening

Interference removal
equipment

Hose
Flexibletask arm
Positioning Platform beamarm
Flexible taskarmFormwork

Positioningarm

Outsourced to TEPCO HD (Implemented in FY2020-21)[Conceptual study of HVH disassembly]➢ Consolidation of pre-conditions➢ Conceptual study of HVH
disassembly methods➢ Identification of issues

Positioningarm
CRD carry-in
entrance

Platform

CRD supporting
structure

CRD
changer

Items to be studied in the future➢

Study of developmental challenges identified during engineeringand technical development, etc.

Middle work
frame

Portion embedded at thepedestal bottom©International Research Institute for Nuclear DecommissioningNo.297
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly
Motor[Issues]• At about 1.5m above the floor inside the HVH there is a motor
which is a heavy object (several 100 kg). It is difficult to remove
it while making sure it does not fall. Hence HVH disassembly
technology that takes fall prevention into consideration needs tobe developed.
[Implementation details]• Requirements for HVH disassembly and removal are studied
and consolidated considering the impact of obstacles such as
the grating installed outside the pedestal and other equipment,etc.
• Element tests are planned and conducted on the remotely
operated equipment for disassembling the HVH and theequipment for cutting and collecting, and the feasibility of
specific disassembly and removal methods is verified.
• The applicability of the equipment, etc. is studied by utilizing
the knowledge obtained during the process of developing andtest manufacturing the equipment for remote operation andother equipment developed so far.
• The viability of cutting and removing equipment that interfere
when the equipment accesses the HVH and carries out
disassembly work, is verified.

Impeller cover

Impeller

Upper
frame

Impeller baseCooling coil

Lower frame
FilterMotor base

Wire
mesh

Overview of the internal
structure of HVH (1F-1)
DHC-1

HPCI-210°

SRV-30CN

HVH-12C

Air
lock
エアロック

PCV
shell
PCVシェルAirlock stage
エアロックステージ

HVH-12B

PCVED-4

Staircase
階段

270°

Equipment
機器ハッチ
hatch
(access
tunnel)(ｱｸｾｽﾄﾝﾈﾙ)

SRV-30D

X-6
HVH-12D
SRV-30A

HVH-12A

90°[Expected outcome]• Presentation of the method of removing HVH

HVH-12E
SRV-30B

Status of the objects on the grating that are to
be removed (1F-1)©International Research Institute for Nuclear DecommissioningNo.298
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢ Consolidation of pre-conditions
In order to select the HVH to be tested from the HVH in Units 1, 2 and 3, following (1) to (3) will be compared and the level ofdifficulty of disassembling HVH will be evaluated.
(1) Accessibility up to HVH(2) Work space(3) Viability of transfer work
However, if the overall evaluation of all the HVHs is the same, the level of difficulty of disassembling pertaining to items
related to work space will take precedence.
(This is because the results of tests conducted during the development carried out so far can be applied to issues related
to accessibility.)
Equipment
hatch

HVH-D

HVH-E

HVH-D

Work space

HVH-E

Interfering objects tobe removed whiledisassembling the
HVH・ MS drain pipes
・ Vacuum breaking
valve
・ Stage・ Staircase
・ Panel・ Support

Equipment hatch
HVH-A

HVH-A
HVH -C

HVH-B

Layout drawing of the first floor of PCV (Unit 1)

HVH -C

Example ofaccess route

HVH-B

Layout drawing of the first floor of PCV (Units 2, 3)©International Research Institute for Nuclear Decommissioning
Note: The contents of this slide are cited from the results of the conceptual studies on HVH disassembly outsourced to TEPCO HD (Implemented in FY2020-21).

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]

No.299① HVH disassembly◼Preconditions [Selecting the HVH to be disassembled]➢ Results of evaluating HVH-A to E in Units 1, 2/3 are given below.
[Legend] Level of difficulty: Difficult (×), Easy (○)
Accessibility up to HVH
No
.

U
ni
t

HVH
No.

Length of theroute

Number of bends

Work space
Number ofinterfering
objects that are
difficult toremoveWorklocation of
the robot (*)

Ratio to the Φ800 work
space at the time ofdisassembling HVH

Viability of transfer work
Number of level
Ratio to the Φ800 work
differences orspace at the time ofslopes that will haveremoving HVH
an adverse impact
on transfer

Comprehensive
evaluation
Difficulty level: High /Medium / Low(Number of instances
evaluated as x) (*)

1

HVH-A

Approx. 21 m [x]3 locations [x]0 locations [〇]Long [○]

2.2 [〇]

2.2 [〇]

0 locations [〇]Level of difficulty: High(x: 2)

2

HVH-B

Approx. 18m [〇]2 locations [x]0 locations [〇]Long [○]

1.8 [〇]

1.8 [〇]

0 locations [〇]Level of difficulty:
Medium (x: 1)

HVH -CApprox. 13 m [〇]1 locations [x]0 locations [〇]Short [×]1.5 [〇]

1.5 [〇]

0 locations [〇]Level of difficulty: High(×: 2)

4

HVH-D

Approx. 4m [〇]0 location [〇]0 locations [〇]Long [○]

3.0 [〇]

3.0 [〇]

0 locations [〇]Level of difficulty: Low(x: 0)

5

HVH-E

Approx. 7 m [〇]0 location [〇]0 locations [〇]Long [○]

2.0 [〇]

2.0 [〇]

0 locations [〇]Level of difficulty: Low(x: 0)

6

HVH-A

Approx. 12 m [〇]0 locations [〇]0 locations [〇]Long [○]

2.6 [〇]

2.6 [〇]

0 locations [〇]Level of difficulty: Low(x: 0)

7

HVH-B

Approx. 10 m [〇]0 locations [〇]0 locations [〇]Long [○]

1.9 [〇]

1.9 [〇]

0 locations [〇]Level of difficulty: Low(x: 0)

HVH -CApprox. 5 m [〇]0 locations [〇]0 locations [〇]Long [○]

1.2 [×]1.2 [×]0 locations [〇]Level of difficulty: High(x: 2)9

HVH-D

Approx. 15 m [〇]1 location [×]0 locations [〇]Long [○]

2.0 [〇]

2.0 [〇]

0 locations [〇]Level of difficulty:
Medium (x: 1)

10

HVH-E

Approx. 18m [〇]2 location [×]0 locations [〇]Long [○]

1.9 [〇]

1.9 [〇]

0 locations [〇]Level of difficulty:
Medium (x: 1)

Approx. 20 m

0.9 location

0 locations

―

1.5

1.5

0 locations

―

3

1

2
/
3

8

Reference value
or average value

Level of difficulty: From the HVH that are difficult to disassemble, those for which the difficulty is related to work space are prioritized, and as the level of difficulty is evaluatedas high for the work of disassembling and removing HVH-C in Units 1, 2/3, HVH-C in Units 1, 2/3 are selected for disassembling.
Note: The contents of this slide are cited from the results of the conceptual studies on HVH disassembly outsourced to TEPCO HD (Implemented in FY2020-21).
©International Research Institute for Nuclear DecommissioningNo.300
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢ The target HVH and the element test policy
The placement of the Unit 1 HVH-C and Unit 3 HVH-C selected for testing is shown below.
As evaluated on the previous page, as the robot will work on the longer side of the Unit 3 HVH-C, theconditions are similar to almost all other HVHs and hence the Unit 3 HVH-C is used as the typical HVH.
Meanwhile, since the robot works on the shorter side only in Unit 1 HVH, if multiple robots and equipment areused in combination for carrying out work, the work contents differ from the other HVHs.
Hence, the element tests are conducted based on the placement of Unit 3 HVH-C. However, the step inwhich multiple robots and equipment are used in combination, the placement of Unit 1 HVH-C is replicated.

PLR pump

PLR pump
Motor

Motor

BlowerBlowerPlacement of Unit 1 HVH-C

Placement of Unit 3 HVH-C©International Research Institute for Nuclear DecommissioningNo.301
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢ Selection of the method of disassembling and removing the HVH

The methods studied and their characteristics are indicated below.
No.

MethodOutlineMeritsDemerits

Evaluation

Hoisting method

The work of separating the heavy
objects from the HVH at elevatedlocations is carried out, the heavy
objects are hoisted using aroughter crane and removed.

• Since the boom of the roughter
crane located at a little distancefrom the HVH is extended to lift
the objects, workspace for the
robots and equipment carrying
out work in the vicinity of the
HVH can be secured.

• In the case of lifting the blower, since the boom and theduct on top of the HVH interfere, the duct needs to be cut.

• It is determined that the hoisting
method can be used as long as
space for extending the outrigger ofthe roughter crane can be secured.
→ Based on the drawing, space can be
secured.
• Based on the drawing, it isdetermined that the duct can be cut.

Method of lifting up

A pallet jack, etc. is set up under
the upper blower unit, the positionof the heavy object is lowered once,
the work of separating the heavy
objects from the HVH is carried out
at a lower location, the heavy
objects are hoisted using aroughter crane and removed.

• Amount of work to be carriedout at elevated locations can be
reduced.
• Cutting the duct which is a
demerit of No.① Hoisting
method, is not required.

• Although it becomes necessary to remove the lower
cooling coil unit while the upper blower unit still remains,since work needs to be carried out on both sides of thelonger side of the HVH, this method may not be viable
depending on the placement of the HVH.
• After setting up the pallet jack, etc., the pallet jack, etc. islikely to interfere and thus it may not be possible toremove the lower cooling coil unit.

• Based on the drawings, since there
are no solutions to the demerits due
to work space, etc., it is determinedthat this method cannot be used.

Cutting (fine cutting) method

Using dedicated cutting equipment,
etc., the heavy objects are finely
cut to a size and weight that canbe handled by a robot, and the cut
pieces are removed using therobot.

• Heavy objects do not need tobe handled.

• It becomes necessary to develop a cutting method thatcan cut the motor.
• Cutting work is expected to take time.

• It is difficult to cut objects that have alarge diameter such as the motor,
but it is determined that this method
can be used for plate materials suchas the blower.

①

②

③

The method of lifting was selected, and the course of removal work was determined based on theconfiguration of the roughter crane (crane) used for lifting and the robot used for the work of
cutting, etc.
©International Research Institute for Nuclear DecommissioningNo.302
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢ Primary concept of the HVH disassembly robot➢ Mounting electronic components (motor driver, etc.) is avoided to the extent possible in order toenhance radiation resistance.

➢ Hydraulic operations cannot be used since oil is likely to leak or flammable gas is likely to begenerated.
➢ Objects located at a height such as the HVH counter top (H2500mm), damper (H3000-2500), etc.
can be removed.
➢ Objects located at a lower level such as the HVH frame, fasteners (on the grating), etc. can beremoved.
➢ The arm can access objects in confined spaces such as the HVH motor, blower, etc.
➢ The heavy objects (motor, blower) are grabbed and hoisted with a crane (roughter crane).
➢ The existing robots and equipment can be used for other works that follow a similar concept or forsmall scale modifications.

Based on these concepts the HVH disassembly robot is studied and test
manufactured.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly

No.303➢ Main specifications of the HVH disassembly robot
Arm tip

Overview of HVH
disassembling robot

Position while travelingSpecifications

Equipment dimensions

Position while checking for a fall

Parts of the arm that can move

Functions and remarks

L1480 x W740 x H1350mm(while moving)

Dimensional constraints from the access tunnel to the equipment hatch: Dimensions such that the equipment can pass throughD1000 x H1500 x L2400mm
The scope of movement of the arm is such that it can cut and remove structures installed on top of the HVH (H2500mm).

Task arm with 10 shafts x 2

One arm grabs and operates the blades. The other arm grabs the disassembled pieces.

Driving mechanism: tires

During the element test, the equipment is driven simply on tires, but on the actual site it is assumed that a crawler will be used.

Work of disassembling and removing
HVH
Incidental work

The work of cutting the HVH, grabbing the disassembled pieces and delivering them will be carried out.
Incidental work such as slinging the hoisting attachment, installing the bird’s eye camera, etc. will be carried out.

Approx. 20kg/arm

Weight capacity for grabbing, moving and operating blades and disassembled pieces.

Approx. 440kg

The equipment is equipped with the required functions, and is as light as possible.
Its structure and mass is such that it will not turn over considering the momentum during work.

Hydraulic pressure

Use of servo motor, etc. that has a low radiation resistance is avoided. The hydraulic mechanism that has a comparatively higher
radiation resistance and draws power from a cylinder, is selected.

Structure

Use

Weight capacity of the work arm

Weight of the equipment

Power©International Research Institute for Nuclear DecommissioningNo.304

6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢ Robots and equipment associated with the work of disassembling and removing the HVH
Assist robot

Crane (for element tests)

Carrying-in/out equipment (For element tests)

Disassembled piece(Motor)Dedicated hoisting
accessory

Overview
diagramCarrying-in/out
equipment

Overview diagram
SpecificationsExplanation

Power: Hydraulic pressure
External dimensions: L1503 x W463 x H575mm
Mass: approx. 100kg

Power: Electric power
External dimensions: L3750 x W920 x 3148mm
Mass: 490kg

Power: None
Internal dimensions: L960 x W760 x H330mm
External dimensions: L1000 x W800 x H732mm
Mass: approx. 90kg
Loaded: 400kg or more

A multi-legged assist robot developed in the pastis used. It assists in removing hoisting equipment,
handling the cable hose, etc. with both task arms.

It is installed on the grating or the beam of thesimulated PCV. During the element test, thescope of movement of the roughter crane that isplanned to be used on the actual site, issimulated and the work of hoisting and delivering
is verified.

The disassembled pieces of HVH are received
and transported up to the equipment hatch. As
the driving test is not to be conducted during theelement test, the external form of the portion thatwill be collected and the portion that will be driven
is simulated and the work up to collection isverified.

©International Research Institute for Nuclear DecommissioningNo.305

6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢ Blades associated with the work of disassembling and removing the HVH (1/ 2)
Tip saw

Centerless tip saw
HydraulicpressurecylinderOverview
diagramHydraulicHydrauliccylindercylinderGrindstone grinder

Motor

Motor

Grindstone

Horizontal direction

Verticaldirection

Blade

Horizontal direction
Horizontal direction

Vertical direction

Specifications

TargetExplanation

Blade

Clampingmechanism

Vertical direction

Hydraulic cylinder

Clampingmechanism

Power: Electric power / hydraulic pressure (stroke)
External dimensions: 323 x 239 x 408mm
Stroke*1: Vertical 75, Horizontal 200mm
Mass: Approx. 15kg

Power: Electric power / hydraulic pressure (stroke)
External dimensions: 305 x 244 x 767mm
Stroke*1: Vertical 200mm, Horizontal 200mm
Mass: Approx. 23kg

Power: Electric power / hydraulic pressure (stroke)
External dimensions: 305 × 150 × 614mm
Stroke*1: Vertical 175mm, Horizontal 100mm
Mass: Approx. 20kg

Damper, panel, casing (blower)

Frame, casing (Blower), cooling coil

Motor shaft, blower shaft, motor base, cooling coil

The tip saw is operated with 2 strokes, and cutting is
performed in a straight line.

The blade of the processed tip saw is used to cut [150channels or block shaped cooling coils that require along stroke.
The clamping mechanism is changed in accordancewith the object to be cut, and cutting is performed while
the object is clamped.

It is used to cut shafts made of hardened carbon steel.
And, it is used to cut motor shafts that are suspended
using a crane.
The clamping mechanism is changed in accordancewith the object to be cut, and cutting is performed while
the object is clamped.

1*: Direction of the stroke with respect to the object to be cut. The vertical direction is the direction in which the cut is made on the object to be cut.
The horizontal direction is the direction in which cutting progresses once the cut is made.
©International Research Institute for Nuclear DecommissioningNo.306

6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢ Blades associated with the work of disassembling and removing the HVH (2/ 2)Hole saw(Additional information) Movement of the blades

Vertical direction② Cutting(Stroke)HydrauliccylinderOverview
diagramHole saw

Specifications

TargetExplanation① Pressing(fixed)② Cutting(Stroke)

Tip saw and hole saw②②CuttingCutting(Stroke)(Stroke)Power: Electric power / hydraulic pressure (stroke)
External dimensions: 400 × 300 × 300mm
Stroke*1: 75 vertical mm
Mass: Approx. 9kg
Damper, panel, casing (blower)
Holes are bored by stroking the hole saw with ahydraulic cylinder.
A Φ60mm hole saw is used for the gripping section of
the gripper.

① Clamp(fixed)Centerless tip saw and grindstone grinder① Clamp(fixed)The blades have a “clamping mechanism” and a “cutting stroke mechanism” respectively.

1*: Direction of the stroke with respect to the object to be cut.
The vertical direction is the direction in which the cut is made on the object to be cut.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢

No.307

Scope of simulation in the element tests associated with the work of disassembling and removing the HVH (Simulated HVH)➢

Lower surface of the duct: The lower surface of the duct interferes with the work carried out on top of the HVH such as
work related to the damper, upper panel, upper frame, etc. Hence the lower surface of the duct is simulated. Note that thedimensions of the area between the top of the HVH and the lower surface of the duct are simulated according to Unit 1
HVH where this area is a confined space.

➢

Site to be cut: The simulated dimensions and material (including equivalent material) are the same as the actual equipment.

➢

Motor impeller: It will not be cut, but its external form and mass are simulated as it will be lifted up.

➢

Cooling coil: The simulated mass (including equivalent material) of the finned tube frame is the same as the actual site. In
order to verify repetitive works, approx. 1/6th of the main body will be simulated for verifying typical work.
Lower surfaceof the duct⑤-2 Upperframe③ Damper⑤-1 Upper
panel⑨ Blower④-2 Frame⑦ Motor④-1 Panel⑪ Cooling coil

Actual HVH (assumed)

Simulated HVH

Simulated HVH (without the panels)©International Research Institute for Nuclear DecommissioningNo.308

6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢ Scope of simulation in the element tests associated with the work of disassembling and removing
the HVH (Surrounding environment)
PLR motor(External form ispartially simulated)

Simulated
HVH

Simulated
HVH

Bird's eye
camera + lights

Blackout
curtain

HVH disassembly
robot
View point of thepicture on the right

PLR motor(External form ispartially simulated)

Grating floor

HVH disassemblyrobot

In the picture on the right, since manned work is underway, there is ambient light.
However, during the test work is carried out with only the light on the arm part of the HVH disassembly robot and the bird's eye camera + lights.
©International Research Institute for Nuclear DecommissioningNo.309

6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢ Work step
The main works from amongst the removal work steps are verified through element tests.
Units 2/3 HVH-C work steps(Work to be performed from the longer side of HVH)

① Access for the cutting equipment

Unit 1 HVH-C work steps(Work to be performed from the shorter side of HVH)

① Access for the cutting equipment② Cutting of connectingpipes⑥ Slinging of heavy
objects (motor)⑨ Cutting of heavy
objects (blower)② Cutting of
connecting pipes⑥ Slinging of heavy
objects (motor)③ Cutting of the damper③ Cutting of the damper⑥ Cutting of the base ofheavy objects (motor)⑩ Cutting and removalof the blower unit

④ Cutting of the panelsof the blower unit

⑥ Cutting of the baseof heavy objects (motor)⑨ Cutting of heavy
objects (blower)④ Cutting of the panels of
the blower unit

⑧ Hoisting and delivery ofheavy objects (motor)⑪ Cutting and removalof the coil unit

⑤ Cutting of the upperpanel⑧ Hoisting and delivery ofheavy objects (motor)⑩ Cutting and removalof the blower unit

④ Cutting of the panelsof the blower unit

⑪ Cutting and removalof the coil unit

⑤ Cutting of the upper
panel⑤ Cutting of the upper
panelWork steps to be tested in the element test
Note: The contents of this slide are cited from the results of the conceptual studies on HVH disassembly outsourced
to TEPCO HD (Implemented in FY2020-21).
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly

No.310➢ Contents to be verified during the element tests
Work
Step

(3) Damper removal(4) Blower unit panel cutting(5) Upper panel cutting(6) Heavy object (motor) slinging

Contents to be verified

Contents

Cutting the damper

To verify the feasibility of the work of cutting at elevated locations and the work of collecting thedisassembled pieces using the HVH disassembly robot, and the feasibility of access for the blades.

Cutting the panel on the outer periphery

To verify the feasibility of the work of cutting at elevated locations and the work of collecting the

Cutting the frame

disassembled pieces using the HVH disassembly robot, and the feasibility of access for the blades.

Cutting the upper panel

To verify the feasibility of the work of cutting at elevated locations and the work of collecting the

Cutting the upper frame

disassembled pieces using the HVH disassembly robot, and the feasibility of access for the blades.

Installing the motor hoisting accessory

To verify the feasibility of slinging work when the HVH disassembly robot and the lifting equipment areused in combination for the Units 2/3 HVH-C.
To verify the feasibility of slinging work when the assist robot and the lifting equipment are used in
combination for the Unit 1 HVH-C.
To verify the feasibility of cutting work when the HVH disassembly robot and the lifting equipment areused in combination for the Units 2/3 HVH-C.
To verify the feasibility of access for the blades.

(7) Heavy object (motor) base cutting

Cutting the motor shaft / baseTo verify the feasibility of cutting work when the assist robot and the lifting equipment are used in
combination for the Unit 1 HVH-C.
To verify the feasibility of access for the blades.
Also, to similarly verify whether the cutting equipment can access, although the structure of the Units
2/3 HVH-C and the motor base are different.

(8) Heavy object (motor) lifting and delivery

Hoisting / delivering the motor(9) Heavy object (blower) cutting

Cutting of casing
Slinging the impeller(10) Blower unit cutting and removal

Cutting the impeller

To verify whether heavy objects can be lifted in confined spaces with the help of lifting equipment
without interfering with the surrounding structures.

To verify the feasibility of the work of cutting at elevated locations and the work of collecting thedisassembled pieces using the HVH disassembly robot, and the feasibility of access for the blades.

Slinging / delivering the impeller(11) Coil unit cutting and removal

Cutting the cooling coil

To verify the feasibility of the work of cutting and the work of collecting the disassembled pieces using the
HVH disassembly robot in confined spaces, and the feasibility of access for the blades.

Note: Each step corresponds to the work steps for Units 2/3 HVH-C on the previous page (Same is the case with the subsequent pages as well.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly

No.311➢ Overview of element test results
Work
Step

(3) Damper removal

BladesContents

Cutting the damper

Tip saw
Hole saw

Judgment〇

Results

It was verified that the damper can be cut and removed.

Tip saw(4) Blower unit panel cutting

Cutting the panel on the outer periphery
Cutting the frame

Hole saw〇

Centerless tip saw

It was verified that the frame can be cut and removed.

Tip saw(5) Upper panel cutting

Cutting the upper panel
Cutting the upper frame(6) Heavy object (motor) slinging

Hole saw

It was verified that the panel can be cut and removed.

〇

It was verified that the upper panel can be cut and removed.
It was verified that the upper frame can be cut and removed.

Centerless tip saw

Installing the motor hoisting accessory-〇

It was verified that the motor hoisting accessory can be installed in the case of the placement in Units 2/3.

〇

It was verified that the motor hoisting accessory can be installed in the case of the placement in Unit 1.
In the case of the placement in Units 2/3, since the motor hoisting accessory and the grindstone

Grindstone grinder(7) Heavy object (motor) base cutting△

grinder interfered, the structure of the motor hoisting accessory needs to be modified.
It was verified that the motor shaft / base can be cut.

Cutting the motor shaft / baseBased on the Units 2/3 results, it was found that similar issues would occur.

-△

It was decided that verification would be performed after modifying the structure of the motor hoisting
accessory in the same manner as Units 2/3, and the test was resumed from the step after cutting.

(9) Heavy object (blower) cutting

Cutting of casing〇

Centerless tip saw〇

It was verified that the casing can be cut and removed.

〇

It was verified that the slinging of the impeller is possible.
It was verified that the impeller can be cut and removed.
It was verified that the impeller can be lifted and delivered.

〇

It was verified that the cooling coil can be cut and removed.

Slinging the impeller(10) Blower unit cutting and removal(11) Coil unit cutting and removal-

Cutting the impeller

Grindstone grinding

Lifting / delivering the impeller

Centerless tip saw
Grindstone grinder

Cutting the cooling coil

It was verified that the motor can be lifted and delivered in the case of the placement in Unit 1.

-(8) Heavy object (motor) hoisting and delivery Lifting / delivering the motor

It was verified that the motor can be lifted and delivered in the case of the placement in Units 2/3.

○ GoodWork steps that are explained on the following pages

Δ Possible but there are issues©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly

No.312➢ Element test results “④ Cutting of the panels of the blower unit”
It was verified that 3 layered panels installed at elevated location canbe cut and removed.
The boring tracks of the hole saw were used for grabbing and thedisassembled pieces were collected without letting them fall.
The tip saw is used to make multiple cuts, but it is difficult to align theposition due to which the cutting lines did not connect. This issue wasresolved by adding a slanted cutting-off assisting line.
Tip saw

Panel

Steel plate

Cutting line

Grabbing
location

Panel

Heat insulating
material©International Research Institute for Nuclear DecommissioningNo.313

6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢

Element test issues “④ Cutting of the panels of the blower unit”

While removing objects that have a broad surface such as damper, panels, etc., the cuttings lines did not connect.
Modifications such as mounting a camera on the blade, etc. so that the operator can verify the area to be cut are
required.
Also, since performing boring in advance using the hole saw so that the cutting lines connect, was an effective
method as well, the cutting plan needs to be studied considering these factors.
.
Tip saw

Cuttingline 2Cuttingline 1

Cuttingline 5View point of the operator

Cutting-off
assisting line

Cuttingline 4©International Research Institute for Nuclear DecommissioningNo.314

6. Implementation Items of This Project [1) (2) Development of Disassembly and RemovalTechnology]① HVH disassembly➢ Element test results “⑦ Cutting of the base of heavy objects (motor)”
It was verified that the shaft and base of the motor installed at an elevatedlocation can be cut and removed without allowing it to fall by working in
combination with a crane.
While cutting the base of the motor, since there were locations that the grindstone
grinder was unable to access, only for such locations temporary slinging wasused to perform cutting work.

Crane(For the test)

Motor

Clamp

Motor

Grindstone
grinder
Motor

Disc

Motor base

Φ55 shaftCutting
location

Coupling

Left arm(Work monitoring)

Cutting
location©International Research Institute for Nuclear DecommissioningNo.315
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢

Element test issue “⑦ Cutting of the base of heavy objects (motor)”

Base B was unable to be cut due to the interference of the motor hoisting accessory and the grindstone grinder.
The plan was to install the motor hoisting accessory after cutting base A, and then to cut base B, but due to theconfined space the grindstone grinder was unable to access it.
At the planning stage the grindstone grinder was expected to be able to access, but the access space reduced dueto the limited field of vision of the operator.
As position alignment is expected to be possible by increasing the field of vision and expanding the access space,
the structure of the motor hoisting accessory needs to be studied once again.
Motor
Motorhoisting
hoisting
accessoryaccessory

Grindstone
grinder

Grindstone
grinder
A

B

D

C

Motor base cutting sequence

Base B

Base B(Back side of the motor)
Simulated boom

©International Research Institute for Nuclear DecommissioningNo.316
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢ Element test results “⑩ Cutting and removal of the blower unit (Impeller)”
It was verified that the shaft of the impeller installed at an elevated location can be
cut and removed without allowing it to fall by working in combination with a crane.
Slinging of the impeller shaft and the work of cutting the impeller shaft were carriedout in a confined space. While cutting the Φ90mm impeller shaft, the efficiency
dropped during the latter half of the cutting process, but it was verified that theshaft can be cut.

Crane hook

CasingWire

Impeller

Grindstone
grinder

Crane(For the test)

Impeller

Φ90 shaft
Clamp©International Research Institute for Nuclear DecommissioningNo.317
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢ Element test issue “⑩ Cutting and removal of the blower unit (Impeller)”
While cutting, the bearing of the disc of the grindstone grinder wore and needed to be replaced.
The structure of the grindstone grinder is such that the disc can be replaced through remote operation, andreplacement is within expectation. However, although replacement of the disc had been expected, wearing of
the bearing had not been expected.
As it is desirable to not have to replace the disc while cutting the shaft, reinforcement of the portion that wears
off needs to be considered.
Drivetransmission part

Eyelet(After the damage)

Eyelet (Before
the damage)

Grindstone grinder

Cutting
location

Φ90 shaft

Clamp©International Research Institute for Nuclear DecommissioningNo.318
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢ Element test results “⑪ Cutting and removal of the coil unit (cooling coil)”
It was verified that the cooling coil can be cut and removed using acenterless tip saw and a grindstone grinder.
However, in either case, cutting efficiency declined severely at a depth of
60mm or more. Also, in the case of centerless tip saw, the disassembled
pieces sometimes got caught into the hole at the center and the saw got
stuck.
Grindstone grinder

Cutting line

Cooling
coil

Disassembly
location

Disassembled
pieces©International Research Institute for Nuclear DecommissioningNo.319
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly➢

Element test issues “⑪ Cutting and removal of the coil unit (cooling coil)”In the case of the centerless tip saw as well as in the case of the grindstone grinder, when deeper cutting was
performed, the area of contact increased due to which the rotational speed decreased leading to a decline in cutting
efficiency. In the case of the grindstone grinder, it was verified that cutting can be performed up to the boundary, but
it took an extremely long time.
Methods to reduce the time required including change in the cutting location needs to be studied.

Tube
Tube

Tube

Tube
Cutting
120mm
deep

Tube

©International Research Institute for Nuclear DecommissioningNo.320
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly: Planned: Planned (after revision)*: Actual◼ Development Process
FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

FY202212

1

2

3Interim Report
▼

4

5

6

Interim Report
▼

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final
report
▼1. Conceptual study

2. Element test plan

3. Test preparation /Test manufacturingof test equipment
4. Element tests

5. Summary

Remarks* The plan was revised to reflect the study progress status and the results of element tests.

©International Research Institute for Nuclear DecommissioningNo.321
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]① HVH disassembly: Summary➢In FY2021, results of studies conducted on HVH disassembly concerning theselection of items to be tested based on the pre-conditions and level of difficultyof disassembly, selection of circular saw and grindstone grinder as the cutting
technology, and identification of element test items based on the disassembly
work steps were compiled. The work steps were examined in detail, issues ineach of the steps were identified, an element test plan was formulated, and thetest items, judgment criteria, etc. were studied.
➢Unit tests (tests conducted using the stand-alone equipment outside thesimulated environment) related to cutting were conducted, and the course of
cutting was substantiated through element test.
➢Element tests were conducted to verify the feasibility of the method ofdisassembling and removing the HVH, and the results were consolidated.
➢Issues in application to the actual facility were identified, and the plan forreflecting them into the equipment design for the actual facility was consolidated.

©International Research Institute for Nuclear DecommissioningNo.322
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger
Development is being carried out concerning disassembly, removal, etc. of interfering
objects for further increasing the scale of retrieval of fuel debris and reactor internal
structures. Technology for verifying the feasibility of the work of cutting and collecting
pipes by accessing the inside of the pedestal within the PCV using remote controlled
equipment, was developed so far.
It is absolutely necessary to remove the CRD exchanger, which is a large structure
located at the center inside the pedestal, in order to ensure accessibility for carryingout the work of retrieval of fuel debris from the bottom part inside the pedestal. Also, as
the pedestal opening from where the remote controlled disassembling equipment willenter inside the pedestal is small, the equipment needs to be able to operate in a small
and uncertain on-site environment. Moreover, any interference with the CRD housing,
etc. which is found to be damaged based on the results of PCV internal investigation,needs to be avoided, and the members of the CRD exchanger that will be disassembled
need to be prevented from falling. During the development concerning this, uponstudying and consolidating the requirements for disassembling and removing the CRD
exchanger, elemental tests using simulated test pieces will be planned andimplemented considering remote operation in limited space, and the feasibility of
specific cutting/collection methods will be verified.

©International Research Institute for Nuclear DecommissioningNo.323
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger
Table of Contents⚫ Status of studies conducted up to FY2020⚫ On-site conditions (Estimation of the status inside the pedestal)⚫ Issues, implementation details and results⚫ Compilation of various pre-conditions
⚫
⚫
⚫
⚫
⚫
⚫
⚫

Study of the method of disassembly and removal
Element test items
Element test plan (Units 1/3)
Designing and test manufacturing of the disassembly and removal equipment (Units 1/3)
Simulated test pieces and test equipment (Units 1/3)
Element test results (Units 1/3)
Issues⚫ Development schedule⚫ Summary©International Research Institute for Nuclear DecommissioningNo.324
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼Status of studies conducted up to FY2020
The method of accessing inside the pedestal and the method of removing small interfering objects
such as the ICM housing, etc. were studied, and prospects of these methods being feasible wereseen through elemental tests.
(Implemented as part of “Further increasing the scale of retrieval (Implemented in FY2019- 20)：
Method of removing interfering objects from inside the pedestal (Small equipment method)”)
CRD
opening
CRD開口Interference object

干渉物撤去装置
removal equipment

CRD
opening
CRD開口Interfering
干渉物
objects

Interfering
干渉物
objects

Processing
tool
加工ツール

Processing
tool
加工ツール

➢ The method of disassembling the CRD exchanger (large structure) that becomes an obstacle in
the work of fuel debris retrieval, within the limited space inside the pedestal is studied.
➢ The disassembling equipment used in this method of disassembling the CRD exchanger is test
manufactured and verified.
©International Research Institute for Nuclear DecommissioningNo.325
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼On-site conditions (Estimation of the status inside the pedestal)➢ The estimated status inside the pedestals in Units 1 - 3 is given below.
Unit 1
CRD opening

Unit 2

Unit 3Structures at the top

Structures at the top

Platform(P/F)

Structures at the
top that havefallen off(CR guide tube)

Illustration
showing thestatus inside thepedestal
CRD
exchanger

Actual status unknown(Damage over and above that in Unit 3 isestimated)

Intermediate
work stand
Platform (P/F)

Results of
estimation•••

The inside of the pedestal has not been
investigated.
(The above figure shows sound conditions)

Deposits
Deposits

The following was estimated based on the resultsof investigation• The platform (P/F) is remaining, and a part of
the grating has fallen off.
• The CRD exchanger is remaining on the P/F.
• The intermediate work stand is remaining.
• There are deposits at the bottom of thepedestal.
(The status inside the deposits is unknown)

CRD exchanger(Buried under thedeposits)

The following was estimated based on the resultsof investigation• The platform (P/F) and the CRD exchanger
have fallen off.
• The structures at the top (CR guide tube, etc.)
have fallen off.
• There are deposits at the bottom of thepedestal.
(The status inside the deposits is unknown)

In Unit 2, the CRD exchanger remains on the P/F, and its location and status have been ascertained. Also, the status of the P/F and theintermediate work stand (places where the grating has fallen off, etc.) has been ascertained.
In Unit 3, the CRD exchanger has fallen off from the P/F, is buried under the deposits, and its location and status have not been identified.
In Unit 1, as damage over and above that in Unit 3 is estimated, it is speculated that the status will be the same as Unit 3.

©International Research Institute for Nuclear DecommissioningNo.326
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Issues
•

•
•
•

•

Ensuring that the disassembly and removal equipment is able to access the areaaround the CRD exchanger.
Disassembling and removing the CRD exchanger, which is a large structure, using asmall equipment that can be carried in through the CRD opening.
Disassembling and removing the CRD exchanger, which is a large structure, into aslarge pieces as possible, in order to improve throughput.
[Specific to Unit 2] Disassembling and removing the CRD exchanger, which is a large
structure that hangs from the platform (P/F), without letting it fall to the bottom of thepedestal.
[Specific to Units 1/3] Disassembling and removing the CRD exchanger (including
other structures) that has fallen and gotten entangled without letting it collapse.

◼ Implementation details
•
•
•
•
•
•
•

Various preconditions including the dimensions, etc. of the structures areconsolidated.
Requirements related to disassembling and removing the CRD exchanger are
studied and compiled.
The method of disassembling and removing the CRD exchanger is studied.
The disassembly and removal equipment is designed and test manufactured.
Element tests are planned considering remote operation in limited space.
Simulated test pieces and full scale testing equipment are designed and test
manufactured for conducting the tests.
Feasibility of specific disassembly and removal is verified by element tests.

◼ Expected outcome•

Presentation of the method of disassembling and removing the CRD exchanger.

CRD opening

Structures at the top

CRDexchanger

Intermediate
work stand
Platform (P/F)

Deposits

Figure illustrating the estimatedconditions inside the pedestal(Unit 2)
CRD opening

Structures at the top

Structures at
the top thathave fallen off(CR guide tube)
Deposits

Platform (P/F)

CRD exchanger(Buried under the deposits)

Figure illustrating the estimatedconditions inside the pedestal(Units 1/3)
©International Research Institute for Nuclear DecommissioningNo.327
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Compilation of various pre-conditions [1/12]
The preconditions at the time of studying the method of disassembling have been compiled under thefollowing 9 items based on the site status and information in the drawings.
①
②
③
④
⑤
⑥
⑦
⑧
⑨

Specifications of the CRD exchanger
Specifications of the P/FSpecifications of the intermediate work standSpecifications of the interfering objects (structures on top of the pedestal) around the CRD
exchanger
Status of the deposits at the pedestal bottom, and scope of removal of the CRD exchanger
Access route to be used
Interfering objects on the access routeTransfer method
Range of access©International Research Institute for Nuclear DecommissioningNo.328
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Compilation of various pre-conditions [2/12] [① Specifications of the CRD
exchanger [1/3]]
No.

Items

Specifications

Remarks

1

Trolley frame[Dimensions]
Height: 400 [mm], Width: 117 [mm],Length: 2,700 [mm][Material]: SS400[Thickness]: 20 [mm]
[Mass]: Approx. about 100 [kg]• The dimensions and plate
thickness are estimates.
• Mass of one side
• Mass is a rough value

2

Wheels fortraveling[Dimensions]
Diameter: Φ100 [mm], Thickness:
143 [mm][Material]: S45C
[Mass]: Approx. about 18 [kg]• The dimensions and plate
thickness are estimates• Mass is a rough value

3

4

Trolley drive
unit

Chain for thelifting carriage[Dimensions], [Material][Thickness], [Mass]: Acquired at the stage of designing
the actual facility

Platform (P/F)

CRD support structures

CRD opening

CRD exchanger

Intermediate
work standBuried part of the pedestal bottom

3

4

1

[Dimensions],[Material], [Mass]: Acquired at the stage of designing
the actual facility
2©International Research Institute for Nuclear DecommissioningNo.329
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger
Platform (P/F)
CRD support structures◼ Compilation of various pre-conditions [3/12] [① Specifications of the CRD
exchanger [2/3]]
No.

Items

5

Rotating
frame

Specifications[Dimensions]
Height: 4,351 [mm]Width: 370 [mm](With shaft for rotating the hoisting axis: 450 [mm])Length: 600 [mm] (estimated)
Diameter of the shaft for rotating the hoisting axis:
Φ100 [mm] (estimated)
Frame rotating equipment shaft: φ75 [mm] (estimated)[Material]:
Frame: SS400
Shaft: S45C (estimated)[Thickness]: 30 [mm]*[Mass]: Approx. about 800 [kg]CRD opening

CRD exchanger

Remarks• The plate thickness is an
estimate.
• Mass is a rough value.

Intermediate work stand

6
6

Frame
rotating
equipment[Dimensions], [Material],[Thickness], [Mass]: Acquired at the stage of designing
the actual facility

7

Grabbing
arm[Dimensions], [Material],[Thickness], [Mass]: Acquired at the stage of designing
the actual facility

8

Hoisting
carriage[Dimensions] (estimated)
Height: 775 [mm], Width: 370 [mm],Length: 270 [mm][Material] SUS304[Thickness]: Approx. 5 [mm]
[Mass]: Approx. about 120 [kg]Buried part of thepedestal bottom

7• Dimension and plate
thickness are estimates.
• Mass is a rough value.

58* Unit 1: Approx. 10 to 20mm.

©International Research Institute for Nuclear DecommissioningNo.330
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger
Platform (P/F)
CRD support structures◼ Compilation of various pre-conditions [4/12] [① Specifications of the CRD
exchanger [3/3]]
No.

Items

Specifications

9

Hoisting drive unit

[Dimensions], [Material],[Thickness], [Mass]: Acquired at the stage of designing
the actual facility

10Power supply unit
(Cableveyor)[Cable size]: Φ25 [mm][Dimensions of connecting plate]
175 x 50 x 10t [mm] (U-shaped steel), Length: 540 [mm][Material]:
SUS304 (Connecting plate, cableveyor)
Aluminum alloy (Cables)[Thickness]: 10 [mm] (Thickness of the connecting plate)[Mass]:
Cableveyor (including the connecting plate): Approx.
about 260 [kg]Cables (on the F/P): Approx. about 20 [kg] per cable

CRD opening

CRD exchanger

Intermediate
work standBuried part of the pedestal bottom

Remarks• Estimate• There are 10 cable (estimated)

9
11

Other
drive units[Dimensions], [Material],[Thickness], [Mass]: Acquired at the stage of designing
the actual facility

12

Overall[Dimensions]
Height: 4,351 [mm]Width: 736 [mm]Length: 2,700 [mm]
Mass: Approx. 2,000 [mm]13

Layout[Height from the opening at the center]
Up to the upper end of the exchanger: 1,170 [mm](From the upper end of the exchanger to the hanger rod:463.2 [mm])Up to the upper end of the actuator: 979 [mm](Upper end of the actuator to the hanger rod: 654.2[mm])• Embedded inside the rotating
frame

10

11

©International Research Institute for Nuclear DecommissioningNo.331
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger

Platform (P/F)◼ Compilation of various pre-conditions [5/12] [② Specifications of the platform(P/F)]
No.

Items

1

Opening G[Dimensions (as per the drawings)]
Width: 755 [mm], Depth: 915 [mm][Dimensions (when deposits are remaining)]
Width: 682.25 [mm], Depth: 765 [mm]• Estimate

2

Opening H[Dimensions (as per the drawings)]
Width: 598.1 [mm], Depth: 1,093 [mm][Dimensions (when deposits are remaining)]
Width: 657.25 [mm], Depth: 893 [mm]• Estimate

3

Opening at thecenter[Dimensions (as per the drawings)]
Width: 596 [mm], Depth: Approx. 2,500[mm]• Estimate• It is assumed that the size of the opening
has not reduced due to deposits.

[Height]: Maximum 38 [mm]• Estimate• Acceptable maximum load of the grating
is assumed to be
250 [kg/m2](This is 50 [%]Note of the general strength
indicator specified by the grating
manufacturer.)

4

5

Grating

LayoutSpecifications[Height]
From the pedestal bottom to the top of thecentral rail:
3,281 [mm]From the pedestal bottom to the P/F
grating:
3,200.8 [mm]From the top of the P/F to the hanger rod:
1,633.2 [mm]CRD opening

CRD support structures

CRD exchanger

Remarks

Intermediate work standBuried part of thepedestal bottom

2

1

3

• Estimated from Unit 4

It is assumed that the P/F cannot rotate
due to damage.
• The acceptable maximum load of the P/F
is assumed to be the same as that of thegrating.
• The P/F and CRD exchanger are
assumed to be fixed. However, thefixation of the P/F is assumed to beunstable (is likely to get detached due toimpact, etc.).

4Note) There are no grounds for 50%. It will berevised if it is found to be difficult to work with.

©International Research Institute for Nuclear DecommissioningNo.332
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger

Platform (P/F)◼ Compilation of various pre-conditions [6/12] [③ Specifications of the intermediate
work stand]
No.

Items

Specifications

1

Opening G2[Dimensions (as per thedrawings)]
Width: 800 [mm], Depth: 915[mm]• Estimate

2

Opening H2[Dimensions (as per thedrawings)]
Width: 800 [mm], Depth: 1,090[mm]• Estimate

CRD opening

CRD exchanger

Remarks

Intermediate work stand3

Grating

CRD support structures

Buried part of thepedestal bottom

2[Height]: Acquired at the stage ofdesigning the actual equipment14

Layout[Height]
From the pedestal bottom to theintermediate work standgrating: 2,192 [mm]

• The intermediate work standand CRD exchanger are
assumed to be fixed. However,the fixation of the intermediate
work stand is assumed to beunstable (is likely to get
detached due to impact, etc.).

3©International Research Institute for Nuclear DecommissioningNo.333
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Compilation of various pre-conditions [7/12] [④ Specifications of the interfering objects (structures on top of the pedestal) around the
CRD exchanger]
Interfering objects that need to be removed before removing the CRD exchanger were identified. The identified items arelisted below.

No.

Interfering
objects

Specifications

1

TIP guide
tube[Outer diameter]:
Φ9.525 [mm][No. of tubes]: 31 tubes[Material]: SUS304-TP• (Unit 4)[Dimensions]:
Height: 75 x 75 x t9 [mm](U- shaped steel)
Length: approx. 1,600[mm](From the top of P/F tothe bottom end: 632.2[mm])[Mass]: Approx. about 25[kg][No. of supports]: 10 - 20
(assumed)[Material]: SUS304(estimated)• Used onlyin Unit 2

2

TIP guide
tube
supportRemarks
1
2

Vertical cross section of the CRD exchanger andother structures inside the pedestal©International Research Institute for Nuclear DecommissioningNo.334
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Compilation of various pre-conditions [8/12] [⑤ Status of the deposits at the pedestal bottom, and scope of removal of
the CRD exchanger]➢

The scope of removal of the CRD exchanger, which is common for Units 1 - 3, includes the structures other than the
CRD exchanger and hoisting carriage that are buried under the deposits at the pedestal bottom. (The CRD exchanger
and the hoisting carriage are assumed to be stuck in the deposits.)
For the CRD exchanger in Unit 2, the hole portion will be cut so that the cross sectional area at the time of cutting
becomes small. Also, in order to secure distance between the cutting position and the deposits for availability of
installation of blades, the CRD exchanger left behind is assumed to be at a height of 360mm# from the surface of thedeposits.

CRD exchanger
The CRD exchanger and hoisting
carriage buried under the fueldebris are left behind.

Distancefrom thedeposits

Cutting
position
360mm*➢

Deposits

Before removing the CRD
exchanger (Example of Unit 2)

After removing the CRD exchanger(Example of Unit 2)#Estimated.

©International Research Institute for Nuclear DecommissioningNo.335
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Compilation of various pre-conditions [9/12] [ ⑥ Access route to be used]•••

The shorter route outside the pedestal from X-1B to the CRD opening is considered as the access route.
The same access route in the reverse order is the route for transporting disassembled pieces of the interfering objects inside
the pedestal.
The equipment for disassembling and removing interfering objects from inside the pedestal, tools, and disassembled pieces
are transferred between the CRD opening and X-1B by loading them on a transportation cart.

Equipment hatch(X-1) 45°

90°

CRD opening
37°

180°

0°

90°

180°

0°

CRD opening
250°

270°

Transportation route in Unit 1

Equipment
hatch
(X-1)
315°

270°

Transportation route in Units 2 and 3©International Research Institute for Nuclear DecommissioningNo.336
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼Compilation of various pre-conditions [10/12] [ ⑦ Interfering objects on the access route]90°
Equipment hatch(X -1B) 45°
Items to be transported

N

Equipment for transferring cut pieces(Example of items to be transported)

Transportation cart

0°

150
0
(1800)••The dimensions of the transportation cart and the travel route mentioned in the previous
pages are given below.
The interfering objects on the access route in Unit 1 and Units 2/3 have been listed up.
Also, the ability to pass through confined spaces on the access route was studied using
the 3D model.

180°

300

•

CRD opening
250°
In the direction of
forward movement

Dimensions of the transportation cart(with the items to be transported loaded)

270°

Transportation cart travel route (Example of Unit 1)©International Research Institute for Nuclear DecommissioningNo.337
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼Compilation of various pre-conditions [11/12] [⑧ Transfer method]•

Equipment fortransferring cut pieces

Structures at
the top
CRD opening

Front
suspension

1981 （Units 2/3)•

An image illustrating the transfer process is shown below.
The equipment and tools to be carried inside the pedestal are transferred by loading them on theequipment carrier or by means of front suspension using a jig.
The cut pieces to be carried outside the pedestal are transferred similarly by loading them on theequipment carrier or by means of front suspension using a jib.
Dimensions of the items to be transferred (Same when loaded on the carrier or suspended in front): Heightless than 750 mm, width less than 750 mm

1970 (Unit 1)••

CRD rail©International Research Institute for Nuclear DecommissioningNo.338

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼Compilation of various pre-conditions [12/12] [ ⑨ Range of access]Pedestal depth(Z direction)

Unit 2

Unit 35000mm

5440mm

5440mm4995.4 mm

5081 mm5081 mm

CRD opening

CRD opening

Inside the pedestal
Φ5000(Range of access)(37°)

2743 1981

5081

Lower end of the
support274 block5081

CRD opening(37°)
Lower end of the
support block

Reference drawings

support block（250°)

1981

Inner diameter of thepedestal(r, θ direction)

Unit 1

273 1971
04995.
4 end of theLower

Range of access••

The entire region inside the pedestal (lower end of the CRD support block and lower) is considered to be the rangeof access.
After entering the pedestal from the CRD opening, an arbitrary location inside the pedestal is accessed.
The range of access inside of the pedestal in Units 1 - 3 at 1F is indicated below.

3•

Inside the pedestal(Range of access)Inside the pedestal(Range of access)
Φ5440

Φ5440

©International Research Institute for Nuclear DecommissioningNo.339

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Requirements related to disassembling and removing the CRD exchanger
(1)

(2)

Requirements with respect to the method• [Specific to Unit 2] The CRD exchanger must be removed with the P/F still left
behind.
(As the CRD exchanger remains on the P/F, it would be difficult to remove the P/F
and the intermediate work stand beforehand)• [Specific to Units 1/3] Structures in the vicinity of the CRD opening must be removed
sequentially.
• Large structures must be able to be transferred through the CRD opening,
and the structures must be cut into pieces that are as large as possible and thentransferred.
(In order to enhance throughput by reducing the number of rounds of cutting.)• Measures must be taken to ensure as much as possible that the cut pieces do not
fall to the bottom of the pedestal.
• Measures must be taken to ensure as much as possible that equipment and tools do
not fall to the bottom of the pedestal.
• The cut pieces, equipment and tools must not be stored temporarily at the bottom of
the pedestal.
• As the integrity of the structures at the top (CRD support structures) inside thepedestal is unknown, equipment must not be installed on the structures at the top.
• As the integrity of the inner wall of the pedestal is unknown, work that requires
anchors to be installed on the inner wall must not be performed.
(The surface of the outer wall of the pedestal may be subjected to load and extended
use of the wall surface on the left, right and upper side inside the CRD transfer outlet
is possible.)
Requirements with respect to the equipment and tools used
• The equipment and tools must be usable under the environmental conditions inside
the pedestal (rainfall from the top of the pedestal, darkness, dose rate: 43Gy/h*1 ormore).
• Special processes such as welding, etc. must not be required to be performed inside
the pedestal.
• Cameras and lights must be installed for better visibility during work.

Platform (P/F)

CRD opening

CRD support structures
CRD exchanger

Intermediate work standBuried part of thepedestal bottom

Illustration showing an overview of the insideof the pedestal (Example of Unit 2)*1) Maximum dose rate outside the pedestal in Unit 2.
(Source: TEPCO website, Results of Internal Investigationof Unit 2 PCV [02/28/2019])©International Research Institute for Nuclear DecommissioningNo.340

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼Study of the method of disassembly and removal of the CRD exchanger
The method and policy for disassembly and removal of the CRD exchanger in Unit 2 and Units 1/3 are indicated below.
Unit 2Illustration
showing the status
inside thepedestal

Disassembly
policy•••Equipment at
the top

Equipmentat the top

Intermediate
work standCRD exchanger
Deposits

Intermediate
work stand
Platform (P/F)

Disassembly
methodUnits 1/3

Deposits

The CRD exchanger will be removed with the P/F still left
behind.
(As the CRD exchanger remains on the P/F, it would be difficult
to remove the P/F and the intermediate work stand beforehand.)CR guide tube

CRD exchanger(Buried under thedeposits)

Platform (P/F)

The structures in the vicinity of the CRD opening (P/F,intermediate work stand, etc.) will be sequentially removed
to secure work space, and then the CRD exchanger will be
removed.

It should be possible to transfer cut pieces of large structures through the CRD opening, and the cut pieces should be as large
as possible.

The disassembly method for Unit 1 and that for Units 2/3 are different, but the disassembly policy is the same for all units, in that it should bepossible to transfer cut pieces of large structures through the CRD opening, and the cut pieces should be as large as possible, in order toenhance the throughput by reducing the number of rounds of cutting.
The work steps involved in the disassembly method for Unit 2 and that of Units 1/3 are described on the following pages.
In the case of Units 1/3, there are many uncertainties (the position and condition of the CRD exchanger, condition of the deposits, etc.). In the
future, the disassembly method will be reviewed at the stage when these uncertainties are eliminated.
©International Research Institute for Nuclear DecommissioningNo.341

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal of the CRD exchanger (Unit 2)

The work steps (overview) involved in the Unit 2 CRD exchanger disassembly and removal, which are to be performed inside the pedestal,
are indicated below.
The study of the method of disassembly and removal targeting Unit 2, the element test plan and the results have been reported in FY2021.

Small robot

Transportationequipment
Rail

Fall preventiontool① Removal of interfering objects (structures on
top of the pedestal)② Installation of rail for equipment access③ Fall prevention measures for the lower CRD exchanger④ Removal of lower CRD exchanger (rotating
frame, etc.)⑤ Removal of upper CRD exchanger (trolley drive
unit, etc.)⑥ Removal of upper CRD exchanger (trolley
frame, etc.)

A rail is installed on the P/F, and equipment and robots are moved to the specified locations over the rail.
©International Research Institute for Nuclear DecommissioningNo.342

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal of the CRD exchanger (Units 1/3) [1/ 8]
The work steps (overview) involved in Units 1/3 CRD exchanger disassembly and removal, which are to be performed inside
the pedestal, are indicated below.

Small robot

Scaffolding

Deposits
Fuel debris① Removal of interfering objects and fallen
objects around the CRD opening

Transportationequipment

Fall prevention
jack④ Fall prevention measures for the objects tobe removed (P/F, etc.)

P/F rotatingrail bracket

Suctionequipment② Suction of deposits and removal of fallen objects
around the CRD opening③ Installation of scaffolding for equipment access

Fall preventionwire⑤ Removal of objects to be removed (P/F, etc.)⑥ Extension of the scaffolding for equipment
access (repeated hereinafter)

The scaffolding is constructed using the P/F rotating rail bracket and the equipment and robots are moved to the specified location
without any load being applied to the fuel debris at the bottom.
©International Research Institute for Nuclear DecommissioningNo.343

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼Study of the method of disassembly and removal of the CRD exchanger (Units 1/3) [2/8]
An image illustrating the construction of the scaffolding using the P/F rotating rail bracket is given below.
CRD opening

Equipment access route(Equipment and robot fortransferring cut pieces)

P/F rotatingrail bracket

Upper scaffolding

Example of placement of scaffolding during the element test
No.
Base unit

Name

1

Base
unit

2

Upper
scaffolding

P/F rotatingrail bracket

Middlescaffolding

Details•

Installed and temporarily clamped on the bracket by suspending and lowering
while avoiding the rail on the bracket, and then a small robot clamps it on the top
and bottom of the bracket using tools.

•

A scaffolding mainly for moving the equipment for transferring cut pieces tospecified locations inside the pedestal.
Positioned on top of the base unit by inserting a pin and installed, and thereafter
fixed by a small robot using tools.

••

Illustration showing placement ofscaffolding inside the pedestal

3

Middlescaffolding••

A scaffolding mainly for moving small robots to specified locations inside thepedestal.
Fixed to the lower part of the base unit with the help of a wire sling or expandable
foot.
The necessity to install the middle scaffolding is determined based on the heightof the fuel debris and deposits at the bottom of the pedestal.
©International Research Institute for Nuclear DecommissioningNo.344

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼Study of the method of disassembly and removal of the CRD exchanger (Units 1/3) [3/8]
An image illustrating the procedure of installing ancillary facilities (construction of scaffolding) inside the pedestals ofUnits 1/3 in 1F is shown below.
CRD opening
Transportationequipment

Structures at the top
Base unit (B)Slope
Upper scaffolding (Outside) (A-B)

P/F rotatingrail bracket (C)Upper scaffolding(Between) (A-B)

Base unit
connecting frame
P/F rotatingrail bracket (A)Base unit (A)Small robot
Middle scaffolding (Right) (A)Beam (Outside) (B)
Lock clip(Small)Middle scaffolding(Left) (A)Middle scaffolding(Right and Left) (B)
Lock clip (Large)

Reference clip

Beam (Outside) (A)Components of a size that can be carried in from the CRD opening are carried inside the pedestal usingtransportation equipment, they are assembled inside the pedestal using small robots. The scaffolding is for moving
the transportation equipment and small robots to specified locations inside the pedestal.
©International Research Institute for Nuclear DecommissioningNo.345

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal of the CRD exchanger (Units 1/3) [4/8]
An image illustrating the procedure of installing ancillary facilities (construction of scaffolding) inside the pedestals of Units 1/3 in
1F is shown below.
Upper scaffolding (B-C)

Upper scaffolding (C-D)

Upper scaffolding (Inside) (A-B)

Beam (Inside) (B)Beam (Inside) (A)Middle scaffolding (Inside) (B)

Lock clip (Small)

Reference clip

Lock clip (Large)
Middle scaffolding (Inside) (A)©International Research Institute for Nuclear DecommissioningNo.346

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal of the CRD exchanger (Units 1/3) [5/8]
An image illustrating the procedure of installing ancillary facilities (construction of scaffolding) inside the pedestals ofUnits 1/3 in 1F is shown below.
Upper scaffolding (D-E)

Upper scaffolding (F-G)
Upper scaffolding (E-F)

Upper scaffolding (H-I)

Upper scaffolding (G-H)
Upper
scaffolding
(I-J)

Upper
scaffolding(J-K)

Hereinafter, similar steps are followed to construct scaffolding along the entire perimeter inside the pedestal.
©International Research Institute for Nuclear DecommissioningNo.347

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal of the CRD exchanger (Unit 1/ 3) [6/ 8]
An image illustrating the procedure for fall prevention of interfering objects inside the pedestals of Units 1/3 in 1F isshown below.
Equipment for transferring cut pieces

Equipment for transferring cut pieces
P/F fall prevention jack

Fall prevention wire
(Fastens together the
CRD exchanger andscaffolding)
P/F

Robot A

Robot AP/F fall prevention

CRD exchanger

CRD exchanger fall prevention

If there are interfering objects in the vicinity of the location where the scaffolding is constructed, the scaffolding and the interfering
objects are fastened with a jig or a wire to prevent them from falling and then disassembly and removal are performed.
©International Research Institute for Nuclear DecommissioningNo.348

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal of the CRD exchanger (Units 1/3) [7/8]
An image illustrating the procedure for fall prevention of interfering objects inside the pedestals of Units 1/3 in 1F is shown
below.
Getting entangled with the structures at the top

Equipment for transferring cut pieces
Equipment for transferring cut pieces
Robot A

Robot A

Telescopic mechanism

CR guide tube fixing toolCR guide tube
Fall prevention jackCR guide tube

CR guide tube fall prevention

CR guide tube fixing toolCR guide tube

CR guide tube
Fall prevention jackPulling out the CR guide tube

If there are interfering objects in the vicinity of the location where the scaffolding is constructed, the scaffolding and the interfering
objects are fastened with a jig or a wire to prevent them from falling and then disassembly and removal are performed.
©International Research Institute for Nuclear DecommissioningNo.349

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal of the CRD exchanger (Units 1/3) [8/8]

The overall work steps*1 (outline) performed inside / outside the pedestal in 1F Units 1/3 are indicated below.

①②

CRD opening
90°
37°

③④

⑧⑨

⑥
・
・
・

⑤
0°

⑤

180°

90°

0°

180°

⑦
270°

⑩
270°

Equipment hatch (X-1) 315°

<Overview of work steps（□： Development target）〉①

Investigation of accessroute up to the area aroundthe CRD opening⑤

Installation of ancillary equipment
inside the pedestal(Construction of scaffolding,installation of cameras and lights, etc.)⑧

Preparation for removal of large
interfering objects (CRD
exchanger, etc.) at the bottom
inside the pedestal *2②

Removal ofinterferences
outside the pedestal

⑥

⑨

③

Installation of ancillary facilities outside thepedestal(Construction of the utility line, installationof cameras & lights, etc.)

Removal and transfer of interfering objects inthe upper part inside the pedestal(Cable, instruments)

Removal and transfer of large
interfering objects (CRD exchanger,etc.) inside the pedestal

⑩

⑦

④

Removal and transfer of small interfering
objects (pieces of broken structures,deposits, etc.) at the bottom of the pedestal

Moving of interfering objects
outside the PCV through the
CRD opening and transfer
outside PCV*1) The schematic diagram shows Unit 3 as an example*2) Fall prevention of interfering objects is included in the preparation for removal.

Carrying-in of equipment andtools inside the pedestal throughthe CRD opening andinvestigation inside the pedestal

Hereinafter steps ④ to ⑩ arerepeated (Sequence of steps is
switched depending on
circumstances)©International Research Institute for Nuclear DecommissioningNo.350

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test items (Units 1/3) [1/2]
Test items for the unit tests and elemental tests were selected from the work steps that were studied.
Unit test*1

Work
Unit

Com
mon
for
Units
1-3

Step

① Installation of ancillaryfacilities outside thepedestal (1/2)② Removal of interfering
objects outside thepedestal

Details

Nece
ssity

Installation of bird's eye camera /lights(Outside the pedestal)Not
required

Utility line installation

Not
required

Cutting/grabbing/moving interfering
objects outside the pedestal

Installation of utility unit

Installation of cable routing
equipment③ Installation of ancillaryequipment outside thepedestal (2/2)④ Investigation insidepedestalNot
required

Notrequired

Notrequired

Installation of carrying-in/out rail

Not
required

Installation of equipment fortransferring the cut pieces

Not
required

Verification of the status of damage

Not
required

ReasonNot required as this is being implemented as part of the
FY2018 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2019 Subsidy Project (Construction of Water
Circulation System).

Not required as this is being implemented as part of the
FY2018 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).
Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this must be tested in a simulated
environment.

Element test*2
Nece
ssity
Not
required

Notrequired

Notrequired

Notrequired

Notrequired

Notrequired

Notrequir
ed

Requi
red

ReasonNot required as this is being implemented as part of the
FY2018 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2019 Subsidy Project (Construction of Water
Circulation System).

Not required as this is being implemented as part of the
FY2018 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).

Not required as this is being implemented as part of the
FY2020 Subsidy Project (Interference Removal Outside
the Pedestal).

Required in order to verify whether or not it is possible todetermine the status of damage when sufficient lights andbird's eye cameras are not installed.

©International Research Institute for Nuclear Decommissioning*1) Unit test: Test conducted with a stand-alone equipment outside the simulated environment.
*2) Element test: Test conducted inside the simulated environment in which the surrounding environment is simulated.

No.351

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test items (Units 1/3) [2/2]
Test items for the unit tests and element tests are selected from the work steps that were studied.
Unit test*1

Work
Unit

1/3

Step

Details⑤
Installation of ancillaryfacilities inside thepedestal⑥ Removal and transfer
of interfering objects
inside the pedestal⑦
Removal and transfer ofsmall interfering objects atthe bottom of the pedestal⑧
Preparation for removal oflarge interfering objects(CRD exchanger, etc.) at
the bottom inside thepedestal⑨
Removal and transfer oflarge interfering objects(CRD exchanger, etc.)
inside the pedestal

Neces
sity

ReasonElement test*2
Neces
sity

ReasonInstallation of bird's eye camera / lights(Inside the pedestal)Not
required

Not required as this must be tested in a simulated environment.

Required

Required in order to verify whether or not the cameras and lights can beinstalled remotely at the designated locations inside the pedestal.

Deployment and extension of thescaffolding inside the pedestal

Required

Required in order to verify that the conditions enable deployment andextension.
(Scaffolding specific to Units 1/3)

Required

Required in order to verify that the rail can be deployed and extended without
interfering with surrounding structures. (Scaffolding specific to Units 1/3)

Not
required

Not required as this is being implemented as part of the FY2020 Subsidy Project(Interference Removal Outside the Pedestal).

Cutting/grabbing/moving pipes and support

Not
required

Not required as this is being implemented as part of the FY2020 Subsidy
Project (Interference Removal Outside the Pedestal).

Set up of deposit suction equipment

Not
required

Not required as the properties of the deposits and whether or not the deposits
can be sucked and collected have not been determined.

Not
required

Not required as the properties of the deposits and whether or not the deposits
can be sucked and collected have not been determined.

Sucking of depositsNotrequired

Not required as the properties of the deposits and whether or not the deposits
can be sucked and collected have not been determined.

Not
required

Not required as the properties of the deposits and whether or not the deposits
can be sucked and collected have not been determined.

Preparation for removal of fallen objects,
and their removal

Not
requiredThis is similar to the work carried out in ⑧’⑨’. As it will be verified in ⑧’⑨’,this test is not required.

Not
requiredThis is similar to the work carried out in ⑧⑨. As it will be verified in ⑧⑨, thistest is not required.

Carrying-in and installation of cutting
equipment

Required

Carrying-in and installation of fall
prevention tools

Required

Moving of the tool for transferring cut
pieces to the periphery of the objects to be
cut

Required

Required in order to verify that the conditions enable moving.

Required

Required in order to verify that the tool can be moved without interfering withsurrounding structures.

Cutting of objects to be removed

Notrequired

Not required as this is similar to Unit 2 Step ⑩.

Not
required

Not required as this is similar to Unit 2 Step ⑩.

Required

Required in order to verify that the conditions enable lifting of cut pieces fromthe pedestal bottom.

Required

Required in order to verify that the cut pieces can be lifted up without interferingwith surrounding structures (fallen objects that have gotten entangled).

Moving of the equipment for transferring
cut pieces outside the pedestal

Not
required

Not required as this is similar to Unit 2 Step ⑩.

Not
required

Not required as this is similar to Unit 2 Steps ⑧⑩⑫.

Transfer of cut pieces outside the pedestal(up to the equipment hatch)

Not
required

Not required as this is being implemented as part of the FY2018 Subsidy
Project (Interference Removal Outside the Pedestal).

Not
required

Not required as this is being implemented as part of the FY2018 Subsidy Project(Interference Removal Outside the Pedestal).

Lifting up of the cut pieces of the objects tobe cut by means of the equipment fortransferring cut pieces.

Required in order to verify that the conditions enable carrying-in andinstallation.

Required
Required in order to verify that the conditions enable carrying-in and installation.
Required

Unit tests and element tests that were determined to be required were conducted.
©International Research Institute for Nuclear Decommissioning*1) Unit test: Test conducted with a stand-alone equipment outside the simulated environment.
*2) Element test: Test conducted inside the simulated environment in which the surrounding environment is simulated.

6. Implementation Items of This Project [1) (2) Development of Disassembly andRemoval Technology]② Disassembly of CRD exchanger◼ Element test plan (Units 1/3) [1/3]

No.352

Images illustrating an overview of the element tests are shown below. Refer to the following pages for the Items to be verified.
✓: Items for verifying workability of remote operations during the element tests

No.

Test classification

Investigation of the status ofdamage - construction ofscaffolding

1
2

3

4

5
6
7

Investigation inside the pedestal(P/F rotating rail bracket)
Installation of ancillary facilities inside
the pedestal(Installation of cameras and lights)
Installation of ancillary facilities inside
the pedestal(Construction
andextensionof
scaffolding)Equipment
accesstospecifiedlocations(Equipment and small robot fortransferring cut pieces)
Fall prevention(P/F, CRD exchanger, CR guide tube)
Cutting off the interfering objects(P/F, CRD exchanger, CR guide tube)
Transfer of cut pieces of the interfering
objects(P/F, CRD exchanger, CR guide tube)

P/F fall prevention removal

CRD exchanger fall
prevention - removal

CR guide tube fall
prevention - removal

✓
✓

✓

✓

✓

✓

✓

✓

✓

✓

✓

✓

✓

✓

✓

✓

✓

©International Research Institute for Nuclear DecommissioningNo.353

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test plan (Units 1/3) [2/3]
The items to be verified in the element tests are indicated below.
No.

Test classification

1

Investigation inside the pedestal(P/F rotating rail bracket)

2

Installation of ancillary facilities inside
the pedestal(Installation of cameras and lights)

3

4

5

Installation of ancillary facilities inside
the pedestal(Construction and extension ofscaffolding)Equipment access to specified locations(Equipment and small robot fortransferring cut pieces)

Fall prevention(P/F, CRD exchanger, CR guide tube)

Overview of tests

Items to be verified

Equipment and small robot for transferring
cut pieces, which are made to hold thecamera for investigation, are operated
remotely, access the target object and verify
its visibility.
Equipment and small robot for transferring
cut pieces, which are made to hold thecameras and lights, are operated remotely,access the target installation location andinstall the cameras and lights.
The equipment and small robot fortransferring cut pieces are operated
remotely, and a series of procedures forconstructing the scaffolding (assembly ofcomponents inside the pedestal) are
performed.

⚫
⚫

Whether the camera can access the target object
That the angle of view of the camera does not have a blind spot⚫

The equipment and small robot fortransferring cut pieces are operated remotely
and are moved on the scaffolding
constructed inside the pedestal (from the
CRD opening to the specified location inside
the pedestal).
The equipment and small robot fortransferring cut pieces are operated remotely,
and the hole drilling tool is positioned on theinterfering object inside the pedestal.
The hole drilling tool is operated remotely,
and a hole is made in the interfering object
inside the pedestal for slinging.
Th e e q u i p m e n t a n d s m a l l r o b o t f o rtransferring cut pieces are operated remotely,
and fall prevention tools (jack, wire) areinstalled on the part where the hole is drilled.

⚫

Whether the cameras and lights can be installed by remote
operation
Whether the interfering objects inside the pedestal interfere (collide,etc.) with the equipment and tools that are installing the camera
and lights
Whether the scaffolding can be constructed by remote operation
Whether the interfering objects inside the pedestal interfere (collide,etc.) with the equipment and tools that are constructing thescaffolding
Whether multiple sets of scaffolding can be connected and fixed(connection and fixing not being possible due to errors inassembly)
Whether the equipment can be moved to the specified location on
the constructed scaffolding
Whether the stack or interfering objects inside the pedestalinterfere (collide, etc.) with the equipment in motion

⚫

⚫
⚫
⚫

⚫

⚫
⚫
⚫
⚫

Whether the tool for drilling the hole for slinging can be set up on
the interfering object inside the pedestal and whether the hole canbe drilled
Whether the blade is broken or whether a stack is present
Whether the fall prevention tools (jack, wire) can be installed on
the interfering object inside the pedestal
Feasibility of fall prevention using the tools (whether fall can beprevented)©International Research Institute for Nuclear DecommissioningNo.354

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test plan (Units 1/3) [3/3]

The items to be verified in the element tests are indicated below.
No.

6

7

Test classification

Cutting off the interfering objects(P/F, CRD exchanger, CR guide
tube)Transfer of cut piec es of theinterfering objects(P/F, CRD exchanger, CR guidetube)

Overview of tests
The equipment and small robot fortransferring cut pieces are operated
remotely, and the blade is positioned on
the interfering object inside the pedestal.
The blade is operated remotely, and theinterfering object inside the pedestal iscut.
The equipment and small robot fortransferring cut pieces are operated
remotely, and a series of procedures fortransferring cut pieces of the interfering
object inside the pedestal (pulling out,
lifting, loading the cut pieces andtransferring them outside the pedestal)
are performed.

Items to be verified
⚫
⚫
⚫

⚫
⚫

Whether the blade can be set up on the interfering object
inside the pedestal and whether the object can be cut.
Whether the blade is broken or whether a stack is present
Whether the interfering object being cut inside the pedestal
falls

Whether cut pieces can be transferred by remote operation
Whether the interfering objects inside the pedestal interfere(collide, etc.) with the cut pieces being transferred, and theequipment and tools that are transferring the cut pieces©International Research Institute for Nuclear DecommissioningNo.355
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [1/13]
The equipment and tools used for the element tests are indicated below.
No.

1

Name

Small
robot

Approximate
dimensions[mm]

Approximate
mass
[kg]

L1,380 x W980
x H670(Arm unfolded)

Approx. 100

Outer appearance (schematic
drawing)Outer appearance (picture)

Overview•

Positioning arm x 4

Task arm x 2

•
•
•

2

Equipmentfortransferrin
g cut
pieces

L1,825 x W600
x H885(When the jib isstowed)

430

Crane

•

Traveling wheel x 4•
L2,640.5 x W1,060
x H1,361.5(When the jib isdeployed)••
Outrigger x 4

Carrier

Up anddown

Swivel••SwivelDeployment

Is provided with 4 positioning arms and 2 task
arms.
While moving on level ground, the robot canlower itself and move in a crawling position.
While moving on the middle scaffolding inside
the pedestal, it clamps the scaffolding andmoves.
It assists in positioning the equipment andtools for transferring cut pieces that aresuspended and lowered with a crane, andperforms the work of slinging and assembling
the scaffolding.

After being installed on the CRD rail, theequipment enters inside the pedestal byremote operation, and travels on the upper
scaffolding inside the pedestal.
Weight that can be lifted and transported
using a crane: 250 [kg]Lifting height: Approx. 5[m]Performs works such as transportation, lifting
and rough positioning of the equipment andtools (including scaffolding components)
loaded on the carrier.
Performs works such as lifting the cut pieces,loading them on the carrier and transportingthem outside the pedestal.
Provided with winding cable at 4 locations forlashing the equipment for transferring cut
pieces to the floor surface, in addition to theoutrigger.

Wire withhook x 2©International Research Institute for Nuclear DecommissioningNo.356

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [2/13]
The equipment and tools used for the element tests are indicated below.
No.

Name

3

Tool forboringholes
forslinging

Approximate
dimensions[mm]

Approximate
mass
[kg]

L272 x W235
x H440.5(For flat plate)10

L269.5 x W368
x H595.5(For curved
surfaces)

Outer appearance (schematic
drawing)Outer appearance (picture)

Overview•

Gripper for the
robot arm

Drill forboring holes
Position determined formaking a hole on theboring target x 2

A tool for boring holes for slinging to
make it possible to lift various typesof cut pieces.
• Boring target:
P/F, CRD exchanger (For flat
plate)
CR guide tube (For curved
surfaces)• Dimensions of the hole to be bored:
Φ25mm x Depth 35mm

Gripper for the
robot arm
Drill forboring holes
Positiondetermined formaking a hole on
the boring target©International Research Institute for Nuclear DecommissioningNo.357

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [3/13]
The equipment and tools used for the element tests are indicated below.
No.

4

Name

P/F
Cutting
tool

Approximate
dimensions[mm]

Approximate
mass
[kg]

L874 x W312.5
x H21821

Outer appearance (schematic
drawing)Outer appearance (picture)

Overview•

Centerless tip saw•

Tool used in common with the HVH
disassembly and removal element tests
The P/F is held and cut.

Clamped portion to
be processed

5

CRD
exchanger
cuttingtool

L672 x W488
x H30224

Position determined on
the target object

Centerless tip
saw

•
•

Tool used in common with the HVH
disassembly and removal element tests
The CRD exchanger (rotating frame) is heldand cut.

Clampedportion to beprocessed

6

CR guide
tube
cuttingtool

L824 x W522
x H25315

Position determined on
the target object•

Clamped portion to
be processed•

Holes are made in the CR guide tube
beforehand, and pins for the positions
determined on the boring target are inserted.
(To prevent misalignment of tools)
The CR guide tube is held and cut.

Pipe saw©International Research Institute for Nuclear DecommissioningNo.358

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [4/13]
The equipment and tools used for the element tests are indicated below.

No.

Name

7

P/F
Fall
prevention
jack

Approximate
dimensions[mm]
L788.1 x W457.5
x H224.2

Approxima
te mass[kg]
10.8

Outer appearance(schematic drawing)
Clamped portion of thescaffolding inside thepedestal

Outer appearance (picture)

Overview••

Clamped portionof the P/F

•

8

9

CR guide
tube
fall
prevention
jack

CR guidetube fixing
tool

L1,180.5 x W350
x H633.5•

36.4
Clamped portion of thescaffolding inside the pedestal

Clamped portion of
the CR guide tube

L1,234 to 2234
x W600.7 x H704

•
•

•

207.5
Clamped portion of the CR
guide tube x 3•

Weight that the jack can handle:
630kg/unit
Provided with a angle misalignment
absorption mechanism consisting of rink+ spring in front of each clamp.
It clamps the base unit on one side and
the P/F on the other side thereby
preventing any falling.

Weight that the jack can handle:
630kg/unit
Provided with a angle misalignment
absorption mechanism consisting of rink+ spring in front of each clamp.
It clamps the base unit on one side andthe CR guide tube on the other side
thereby preventing any falling.

Lifting capacity of each clamped location:
150kg
A tool that is provided with 3 clamped
locations and a telescopic mechanism,
which fastens the CR guide tube (top andbottom) after pulling out the cut pieces.

©International Research Institute for Nuclear DecommissioningNo.359

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [5/13]
The equipment and tools used for the element tests are indicated below.
No.

Name

10

Scaffolding
inside thepedestal

Approximate
dimensions[mm]

Approxima
te mass[kg]

Approx. L1,700
x W885.2 x H1,804

570

Outer appearance (schematic drawing)／Outer appearance(Photograph)
CRD opening
P/F rotating rail
bracketUpper scaffolding(Outside)
Upper scaffolding(Between)

Overview•

Upper scaffolding(Inside)Beam (Inside)•

Beam (outside)(Regularscaffolding)•Base unit
Middle scaffolding(Right)Middle scaffolding(Left)

Base unit
connecting
frameSame as theprocedures
mentioned on theleft (No. 2)

The scaffolding components indicatedon the following pages are assembled
inside the pedestal.
Scaffolding components are fastened
together with a clamp.
2 sets of components are arranged for.

Hanging
wire
Middle scaffolding(Inside)©International Research Institute for Nuclear DecommissioningNo.360

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [6/13]
The equipment and tools used for the element tests are indicated below.

No.

Name

11

Simplescaffolding

Approximate
dimensions[mm]
L1,650 x
W1,842x H2,982

Approximate
mass
[kg]

Outer appearance(schematic drawing)

Outer appearance (picture)

Overview•

540

Regularscaffolding•

Simplescaffolding

12

Base
unit

L810 x W508 x
H717

69.4

P/F rotating rail bracket clamp part x 2

•
•
•

13

Base unit
connection
frame

L963.2 x
W427.3x H366•

27.3
Base unit clamp
part x 2

Clamp part ofneighboring base unit•

From the viewpoint of deadline and thecost, it is not possible to provide regularscaffolding all around the inner
circumference of the pedestal. Hence
simple scaffolding equivalent to the sizeof 2 sets of regular scaffolding isprovided.
Manually fastened at the base of the
P/F rotating rail bracket, with feet
resting at the bottom of the pedestal.
Fits into the P/F rotating rail bracket
from the top with its own body weight.
The top socket is operated with therotating tool, and the base unit isclamped at the top and bottom.
The remaining scaffolding components
are connected to the base unit.

Neighboring base units are connected
and fixed.
The top socket is operated with therotating tool, it is extended and retracted(fine adjustment of the distance
between the base units) and is clamped.

©International Research Institute for Nuclear DecommissioningNo.361

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [7/13]

The equipment and tools used for the element tests are indicated below.
No.

Name

14

Beam
(Outside)

Approximate
dimensions[mm]

Approxima
te mass[kg]

L770 x W346 x H539

65.8

Outer appearance(schematic drawing)
Base unit
clamp part x 4Outer appearance (picture)

Overview
•
•
•

15

Beam
(Inside)L1,083 x W430
x H319(Stand-alone beam)
L1,083 x W588
x H319(Beam + Middle
scaffolding)

52.6(Standalone
beam)

Beam (Inside) clamp part x 2
Clamp part while
carrying in the middle
scaffolding (Inside) x 2

•
•

•
65.5
(Beam +
Middlescaffolding)•

Fits into the base unit from the top with
its own body weight.
The top socket is operated with therotating tool, and the base unit isclamped at the top and bottom.
The upper scaffolding is installed on top.

Fits into the beam (Outside) from the top
with its own body weight.
The top socket is operated with therotating tool, and the base unit isclamped at the top and bottom.
The base is provided with a clamp partfor fixing the middle scaffolding (Inside).
# Form when it is carried inside thepedestal
The upper scaffolding is installed on top.

Beam (Inside)
Middle scaffolding(Inside)©International Research Institute for Nuclear DecommissioningNo.362

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [8/13]
The equipment and tools used for the element tests are indicated below.
No.

Name

16

Hanging
wire

Approximate
dimensions[mm]
L186 to 784

Approximate
mass
[kg]

Outer appearance (schematic
drawing)―Outer appearance (picture)

Overview••

17

Middlescaffolding(Left /
Right)

L800 x W448 x H243

37.7
Steady bracefeet x 2

•
•
•
•

18

Middlescaffolding(Inside)L800 x W588 x H135

12.9

•
•
•

Wire for connecting the scaffolding
components with each other (in a suspended
state).
Multiple wires of varied lengths in accordancewith the use application are arranged for.

Connected to the underside of the base unit.
2 types of middle scaffolding that are mirror
images of each other are arranged for.
While carrying in, it is connected to the baseunit with a hanging wire and suspended.
Thereafter, the steady brace feet are deployed
and are actually connected to the base unit.

Connected to the beam (inside) with a hanging
wire and suspended.
Fastened to the middle scaffolding (left/right)
with a lock clip (small).
The load is borne by the hanging wire.

©International Research Institute for Nuclear DecommissioningNo.363

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [9/13]
The equipment and tools used for the element tests are indicated below.
No.

Name

19

Middlescaffolding
lock clip

Approximate
dimensions[mm]
L87 x W325 x H320

Approximate
mass
[kg]
7.8

Outer appearance(schematic drawing)
Middle scaffolding
clamped part x 2Outer appearance (picture)

Overview••(Small)••20

Middlescaffolding
lock clip

L147 x W375 x H325

15.8

Middle scaffolding
clamped part x 2••(Large)•21

Referenceclip

L210 x W300
x H171.3

5.6••

A fixing jig for connecting and fixing the
middle scaffolding (left/right) and the middle
scaffolding (inside) to form a single set.
Used for fixing the middle scaffolding (left)
and the middle scaffolding (right) as well.
Fits into the middle scaffolding from the top
with its own body weight.
The top socket is operated with the rotating
tool, and the clip is clamped at the top andbottom
A fixing jig for connecting and fixing the
middle scaffoldings that are connected to forma single set with the lock clip (small) for the
middle scaffolding.
Fits into the middle scaffolding from the top
with its own body weight.
The top socket is operated with the rotating
tool, and the clip is clamped at the top andbottom.

A jig for correcting the position of the middle
scaffoldings before installing the lock clip
(large) for the middle scaffolding.
Fits into the middle scaffolding from the top
with its own body weight and does not need aclamping mechanism.

©International Research Institute for Nuclear DecommissioningNo.364

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [10/13]
The equipment and tools used for the element tests are indicated below.
No.

Name

22

Upper
scaffolding(Outside)

Approximate
dimensions[mm]
L405 x W885.2
x H236

Approximate
mass
[kg]
58.4

Outer appearance (schematic
drawing)Outer appearance (picture)

Overview
•
•
•

23

Upper
scaffolding(Between)

L435.8 x W730
x H236

55.2

•
•
•

24

Upper
scaffolding(Inside)L556 x W804.4
x H236

85.4

•
•
•

Installed on the adjacent beam (outside).
The top socket is operated with the rotating
tool, and the beam (outside) is clamped at
the top and bottom.
The top surface has a punched structure sothat the cooling water can pass through theholes to the bottom of the pedestal.

Installed on the adjacent beam (outside).
The top socket is operated with the rotating
tool, and the beam (outside) is clamped at
the top and bottom.
The top surface has a punched structure sothat the cooling water can pass through theholes to the bottom of the pedestal.

Installed on the adjacent beam (inside).
The top socket is operated with the rotating
tool, and the beam (outside) is clamped at
the top and bottom.
The top surface has a punched structure sothat the cooling water can pass through theholes to the bottom of the pedestal.

©International Research Institute for Nuclear DecommissioningNo.365

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [11/13]
The equipment and tools used for the element tests are indicated below.
No.

25

Name

Slope

Approximate
dimensions[mm]

Approximate
mass
[kg]

L200 x W516 x H79.7

1.1

Outer appearance(schematic drawing)

Outer appearance (picture)

Overview••

26

Socketrotating
tool

―

―

•
•

27

Liftinghook

L177 x W77.3 x H91

1.9

•
•
•
•

Provided for eliminating the gap between the
distal end of the CRD rail and the upper
scaffolding (outside).
Pins are inserted in the holes on the top
surface of the upper scaffolding (outside), andthe slope is fastened to the protruding parts on
the top surface of the CRD rail.

A tool for operating the socket for various tools(scaffolding components, etc.) and fastening
tools together.
Motor operated tools available on the market
are used for the element tests.

Hook for slinging when various equipment,
tools and cut pieces are lifted up.
The method of slinging by inserting pins in theholes.
When held by the arm in the middle, theprotrusion on the sides of the pin gets lowered,and it becomes possible to remove the pin.
As compared with the usual carbine hook, thishook is easier to operate with the robot arm
and the risk of inadvertent slipping is lower.

©International Research Institute for Nuclear DecommissioningNo.366

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [12/13]②①： Camera at the tip of the right task arm②： Camera at the tip of the left task arm[Camera specifications: For vehicularinstallation]①①

Task arm

Scaffolding components

Small robot

Left front footRight front footScaffolding
components

Scaffolding
components

Work during which the small robot is fastened on to the lateral surface ofthe scaffolding component

Left front footRight front footVerification of the grabbing location using
the camera at the arm tip

Element tests were conducted by installing a camera on the small robot.
©International Research Institute for Nuclear DecommissioningNo.367

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (Units 1/3) [13/13]③②④①： Front camera②： Camera at the tip of the jib (facing
downwards)③： Rear camera④： Camera at the tip of the task arm[Camera specifications: For vehicularinstallation]①

Scaffolding
components

CRD rail

Scaffolding components

CRD railWork of carrying the scaffolding components
inside the pedestal①②

Scaffolding
components③④

Tip of the
CRD rail

Element tests were conducted by installing a camera on the equipment for transferring cut pieces©International Research Institute for Nuclear DecommissioningNo.368

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Simulated test pieces and test equipment (Units 1/3) [1/4]
Bracket F

Work stage
CRD rail

P/F

Bracket G
Bracket H

Bracket E
Bracket I
Bracket D

Bracket J
Bracket C
CR guide tube

Bracket K
Bracket B
CRD exchanger

CR guide tube
P/F
Brackets A to K

CRD railBracket A
CRD exchanger

Test equipment simulating the inside of the pedestal in
Units 1/3 (Bird's eye view)

Test equipment simulating the inside of the pedestal in
Units 1/3 (Layout drawing)©International Research Institute for Nuclear DecommissioningNo.369

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Simulated test pieces and test equipment (Units 1/3) [2/4]Name of thestructure in thesimulated test
equipment

No.

Approach towards selection and placement

Approach towards fall prevention

1

P/F

Selected as the structure in the vicinity of the CRD opening
while referring to the results of the internal investigation of 1F3. Placed in an inclined manner so that it blocks the opening.

Prevented from falling by fastening it to a component(base unit) of the scaffolding constructed inside thepedestal using tools.

2

CRD exchanger

Selected as a structure that is large in size and has a large
board thickness (rotating frame). Laid down at the bottom as it
has not been seen during the internal investigation of 1F-3
(assumed to be buried under deposits).

Prevented from falling by fastening it with a wire froma scaffolding component (beam) as it is likely to havefallen to a location lower than the component (baseunit) of the scaffolding constructed inside the pedestal.

3

CR guide tube

Selected as the structure that has fallen from above whilereferring to the results of the internal investigation of 1F-3.
Placed so that it is held up in the wood of the CRD.H.

Prevented from falling by fastening it to a component(base unit) of the scaffolding constructed inside thepedestal using tools.

4Work stage

The height of the lower end of the interfering object (CRD.H) in
the upper part inside the pedestal is simulated.

―©International Research Institute for Nuclear DecommissioningNo.370

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Simulated test pieces and test equipment (Units 1/3) [3/4]
CRD opening
CRD opening

CR guide tube

CR guide tube
CRD exchanger

P/F rotating rail bracket

P/F

CRD exchanger
P/F

Element tests were conducted using the test equipment simulating the inside of Units 1/3
pedestal and the simulated fallen structures.
©International Research Institute for Nuclear DecommissioningNo.371

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Simulated test pieces and test equipment (Units 1/3) [4/4]
Camera ① (Also serves as the camera forinvestigation)[Installation location: Rotating rail bracket]

Rotating rail bracket

Upper scaffolding

Camera specifications: CID color
camera (Pan tilt)

Camera ②[Installation location: Upper scaffolding,
middle scaffolding]

Middle scaffolding

Camera specifications: CANON VB-M44

Element tests were conducted with cameras and lights installed on the upper scaffolding, middle scaffolding
and rotating rail bracket in accordance with the progress in constructing the scaffolding inside the pedestal.
©International Research Institute for Nuclear DecommissioningNo.372
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test results (Units 1/3) [1/7] [Investigation of the status of damage (P/F rotating rail bracket)]An overview of the results of the element tests is given below.
(a) Carrying inside the pedestal
Equipment fortransferring cut pieces(b) Approaching the bracket camera
Task arm(c) Verifying the status of damage

Image from therecording camera

Winch
CRD opening
Bracket (A)(To be investigated)
Bracket (B)Image from the camera
for investigation (Location (a))

Image from the camera forinvestigation (Location (b))

Image from the camera
for investigation (Location (c))

Image from the camera forinvestigation (Location (d))

Camera forinvestigation
Jib wire

Image from therecording camera

Task arm(c)(d)

Camera for investigation

Task arm

Camera for investigation

(b)

(a)

It was verified that the task arm holding the camera for investigation can approach the P/F rotating rail bracket in the vicinity of the
CRD opening, and the fillet welded part of the bracket can be captured in the angle of view of the camera (Prospects of being able
to verify the status of damage of the bracket in the actual facility were seen.)©International Research Institute for Nuclear DecommissioningNo.373

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test results (Units 1/3) [2/7] [Construction of scaffolding inside the pedestal]
An overview of the results of the element tests is given below.
(a) Installing the base unit on the P/F rotating rail bracket
Bracket (B)(b) Installing the middle scaffolding

Image from the task
arm camera

Base unit

Image from therecording camera

Task arm
Robot
Base unit

Middlescaffolding

P/F rotatingrail bracket

Base unit

Robot

Middlescaffolding

Base unit(c) Fastening base units together and correcting
misalignments
Base unit (B)(d) Installing the upper scaffolding

Image from the task
arm camera

Image from therecording camera
Upper scaffolding
Beam (A)Base unit
connecting frame
Fastening andcorrection of
misalignment(extension andretraction)

Beam (B)Upperscaffolding

Tool for operating
the socket

Beam (A)Base
Unit (A)The feasibility of the procedure for constructing the scaffolding for carrying in components through the CRD opening using
equipment and small robots for transferring cut pieces, performing assembly work inside the pedestal, and moving the equipment
and small robots to specified locations inside the pedestal, was verified.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]No.374② Disassembly of CRD exchanger◼ Element test results (Units 1/3) [3/7] [Construction of scaffolding inside the pedestal]
An overview of the results of the element tests is given below.
(e) Extending the beam and the middle scaffolding(f) Extending the upper scaffolding

Image from therecording camera

Beam (A)Upper scaffolding(Inside)Image from therecordingcameraRobot

Middle scaffolding(Inside)Beam (A)Upper scaffolding(Inside)Middle scaffolding(Inside)(g) Installing the base unit on the adjacent bracket(h) Extending the scaffolding in the circumferential
direction

Image from therecordingcameraUpper scaffolding(B-C)

Upper scaffolding(B-C)

Image from therecording camera

Upper
scaffolding
(A-B)

Base
unit (C)Baseunit (C)Upper
scaffolding(A-B)

The feasibility of the procedure for constructing the scaffolding for carrying in components through the CRD opening using equipment and small
robots for transferring cut pieces, performing assembly work inside the pedestal, and moving the equipment and small robots to specified
locations inside the pedestal, was verified.
©International Research Institute for Nuclear DecommissioningNo.375

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test results (Units 1/3) [4/7] [P/F fall prevention, cutting, transfer of cut pieces]
An overview of the results of the element tests is given below.

(a) P/F fall prevention(b) P/F cutting
Image from thebird’s eye camera
inside the pedestal

Image from therecording camera

P/F

P/F

P/F
Cutting
positionP/F cutting
tool
P/F fall prevention
jack

Upper
scaffolding
Clamp
P/F cutting
tool

P/F fall prevention
jack(c) Transferring P/F cut pieces
Image from therecording camera

P/F cut piece

Image from the bird’s eye
camera outside thepedestal

P/F cut piece

P/F cut piece

Prospects of being able to achieve fall prevention of the P/F by connecting it to the scaffolding inside the pedestal with a jack,being able to cut it using the blade that has been remotely positioned, and being able to transfer cut pieces outside the pedestal
by suspending them in front with the jib of the equipment for transferring cut pieces, were seen.
©International Research Institute for Nuclear DecommissioningNo.376

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test results (Units 1/3) [5/7] [CRD exchanger fall prevention, cutting, transfer of cut pieces]

An overview of the results of the element tests is given below.
(a) CRD exchanger fall prevention
Scaffolding inside
the pedestal

Image from therecording camera(b) Cutting of the CRD exchanger
Image from therecording camera

Scaffolding inside thepedestal
Fall prevention
wire

Robot

Fall
prevention
wire

Blade for cutting
the CRD
exchanger

CRD exchanger

Blade forcutting the CRD
exchanger

CRD exchanger(c) Transferring the cut pieces of the CRD exchanger
Cut pieces of the CRD exchanger

Image from the bird’s eye
camera outside thepedestal

Image from therecording camera

Cut pieces of the
CRD exchanger

Cut pieces of the
CRD exchanger
Cut pieces of
the CRD
exchanger

CRD exchanger(remaining portion)

Image from therecording camera

Fall prevention
wire

Outrigger

Wire for lashing
to the carrier

Prospects of being able to achieve fall prevention of the CRD exchanger by connecting it to the scaffolding inside the pedestal with awire, being able to cut it using the blade that has been remotely positioned, and being able to lift and load the cut pieces on to the carrierof the equipment for transferring cut pieces and transfer the cut pieces outside the pedestal, were seen.
©International Research Institute for Nuclear DecommissioningNo.377

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test results (Units 1/3) [6/7] [CR guide tube fall prevention, cutting, transfer of cut pieces, pulling out]
An overview of the results of the element tests is given below.
(a) CR guide tube fall prevention
Image from therecording camera
CR guide tube
fixing tool
(Clamp ②)
CR guide
tube
fixing tool(b) Cutting of the CR guide tube
CR guide tube
fixing tool
(Clamp ①)

Clamp
Cutting position

Clamp ①
CR guide tube fixing tool
(Clamp ③)

Clamp ②
Clamp ③

CR guide tube fall
prevention jackCR guide tube
fixing tool
(Clamp ③)

Blade forcutting the CR
guide tube

CR guide tube fall
prevention jack(c) Transferring the cut pieces of the CR guide tube

Image from therecording camera(d) Pulling out from the structures in the upper partof the pedestal

Cut pieces of CR guide tube

Image from therecording camera

Cut pieces of
CR guide tube

Blade for cutting
the CR guide tube

Simulated lower
end of CRD.H

Image from therecording camera

PullingoutClamp ①

Clamp ③
Clamp ②

Clamp ②

Image from the recording camera

Clamp ③

Prospects of being able to achieve fall prevention of the CR guide tube by connecting it to the scaffolding inside the pedestal with a jack,being able to cut it using the blade that has been remotely positioned, and being able to lift and load the cut pieces on to the carrier of theequipment for transferring cut pieces, and being able to transfer and pull out the cut pieces outside the pedestal, were seen.
©International Research Institute for Nuclear DecommissioningNo.378

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Element test results (Units 1/3) [7/7] [Summary of element test results]

Results of the element tests are summarized below.
No.

Test classification

Test results

1

Investigation of the status of damage(P/F rotating rail bracket)• It was verified that the task arm holding the camera for investigation can approach the P/F rotating rail bracket in thevicinity of the CRD opening, and the fillet welded part of the bracket can be captured in the angle of view of thecamera (Prospects of being able to verify the status of damage of the bracket in the actual facility were seen.)2

Construction of scaffolding inside thepedestal(Including installation of cameras andlights)• A bird's eye camera was installed inside the pedestal using the equipment for transferring cut pieces and small robots
and the feasibility of the procedure for constructing the scaffolding for carrying in components through the CRD
opening using equipment and small robots for transferring cut pieces, performing assembly work inside the pedestal,and moving the equipment and small robots to specified locations inside the pedestal, was verified.

3

Equipment access to specified locations(Equipment and small robot fortransferring cut pieces)• Prospects that equipment can access specified locations, were seen since the equipment for transferring cut pieces
moves over the upper scaffolding constructed inside the pedestal, and the small robots move over the middle
scaffolding.

4

Fall prevention(P/F, CRD exchanger, CR guide tube)• Prospects of being able to achieve fall prevention of P/F by connecting the P/F and the scaffolding inside the pedestal
with a jack, were seen.
• Prospects of being able to achieve fall prevention of the CRD exchanger by connecting the CRD exchanger and thescaffolding inside the pedestal with a wire, were seen.
• Prospects of being able to achieve fall prevention of CR guide tube by connecting the CR guide tube and thescaffolding inside the pedestal with a jack, were seen.

5

Cutting off the interfering objects(P/F, CRD exchanger, CR guide tube)• Prospects of being able to cut the P/F, CRD exchanger, CR guide tube using the blade that has been remotely
positioned with the help of equipment for transferring cut pieces and small robots, were seen.

6

Transfer of cut pieces of the interfering
objects(P/F, CRD exchanger, CR guide tube)• Prospects of being able to transfer the cut pieces of P/F outside the pedestal through the CRD opening bysuspending them in front using the jib of the equipment for transferring cut pieces, were seen.
• Prospects of being able to transfer the cut pieces of the CRD exchanger and the cut pieces of the CR guide tube
outside the pedestal through the CRD opening by loading the cut pieces on the carrier of the equipment fortransferring cut pieces, were seen.
• Prospects of being able to pull out the CR guide tube from the structures in the upper part of the pedestal using the
CR guide tube fixing tool, were seen.

©International Research Institute for Nuclear DecommissioningNo.379

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger◼ Issues identified based on the element tests
Issues identified based on the CRD exchanger disassembly element tests are described below.
No.

Test classification

Issues1

Investigation of thestatus of damage

There are very few camera images that can be used. There is no camera that can provide
a bird's eye view to verify the overall position of the equipment in operation and thepresence of interference with the structures inside the pedestal (There is a similar issue
with the construction of scaffolding inside the pedestal mentioned in No. 2 below.)

A bird's eye camera to be used while investigating the status of damage
should be installed in the vicinity of the CRD opening.

2

Construction ofscaffolding inside
the pedestal

Method for verifying completion of rotation of the socket.

Marking should be added. The structure should be modified so that theclamp pad is visible from the outside.

Structure of the interface (tilted correction) between the base unit and the pedestal.

The structure of the interface should be modified such that it can beextended and retracted (actuator).

Simplification of procedures for installing the middle scaffolding (method of suspending
without using a robot).

The method should be modified so that the upper scaffolding and the middle
scaffolding form an integrated structure and it gets deployed inside thepedestal.

The swinging movement of the arm of the robot on the middle scaffolding is difficult due tointerference with the hanging wire, etc. of the middle scaffolding.

Along with the measures mentioned above, the number of hanging wires
should be reduced.

Fall prevention measures for the equipment for transferring cut pieces while installing thebase unit (C).

A structure that stretches along the inner wall of the CRD opening should be
added to the equipment for transferring cut pieces.

There is no camera for verifying the clamping status of the clamp part of base unit (C).

A camera with extendable tools should be used as required.

The P/F fall prevention jack clamp part (wrist) follows the P/F.

The structure should be modified to that including an actuator rather thanfollowing by means of a spring.

Controlling the tool rotation while suspending the tool for making holes.

The hanging ceiling should be adjusted. The cable feed should be adjusted.

The edge (entire tool) gets damaged at the time of making holes and holes cannot bemade anymore.

A clamping mechanism corresponding to the shape of the location where thehole is to be made should be added to the hole making tools.

Reduction in the frequency of rotational stops because of getting wedged between theblades while cutting the rotating frame

Changing the cutting method from tip saw to grindstone grinder should beconsidered.

Enhancing the stability while making holes on and cutting the CR guide tube, reducing therequired time, increasing the service life of the blade.

The mechanism for clamping the tool on to the CR guide tube (clamping
force) should be modified.

Whether it will be possible to perform cutting if there are any structures inside the CR guidetube and measures against falling of cut pieces.

Internal investigation should be carried out after making the holes. If there
are any embedded objects, the objects should be finely cut and removed.

Measures against interference of the clamp part with the upper CR guide tube when the
CR guide tube is being pulled out.

The structure of the clamp part that interferes should be changed from one
that opens only on one side to one that opens on both sides.

3

4

5

Fall prevention

Cutting off theinterfering objects

Transfer of cut
pieces of theinterfering objects

Countermeasures (Considering the actual facility)©International Research Institute for Nuclear DecommissioningNo.380

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger: Planned: Planned (after revision)*: Actual◼ Development Schedule
FY2021

FY2022

Study items
4

Major milestones

5

6

7

8

9

10

11

12

1

2

3

4

5

Interim Report▼

67Interim Report
▼

8

9

10

11

Interim Report
▼

12

1

2

3

Final report▼

1. Conceptual study

2. Element test plan

3. Test preparation /Test manufacturingof test equipment

Basic tests related to fall prevention and transfer of cut pieces

4. Element tests

5. Summary

Remarks* The plan was revised to reflect the progress status of the studies and the results of basic tests.

©International Research Institute for Nuclear DecommissioningNo.381

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]② Disassembly of CRD exchanger: Summary➢ The pre-conditions pertaining to the disassembly of the CRD were consolidated, the method ofdisassembly and removal of CRD exchangers in Units 1 to 3 and the work steps involved werestudied, and the test items were selected.
•
Unit 2: The method of carrying out disassembly and removal by installing a rail on the
P/F, and moving the equipment to the specified locations inside the pedestal by
traveling over the rail.
•
Units 1/3: The method of carrying out disassembly and removal by constructing ascaffolding inside the pedestal using the P/F rotating rail bracket on the inner wall of thepedestal, and moving the equipment to the specified locations inside the pedestal by
traveling over the scaffolding.
➢ The simulated facility, test pieces, equipment and tool used in the element tests were test
manufactured separately for the Unit 2 base and for the Units 1/3 bases, the work steps were
substantiated, and the element test plan was formulated.

➢ The feasibility of the method of disassembling and removing the CRD exchanger was verified
through element tests. Issues in application to the actual facility were identified and reflected
into the equipment design for the actual facility.

©International Research Institute for Nuclear DecommissioningNo.382

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit
A submersible pump needs to be installed in the pump pit inside the PCV as one of the methods
for circulating water inside the PCV while increasing the scale of retrieval of fuel debris andreaction internal structures. Elemental tests have been conducted based on development carriedout in the past and it has been projected that the pump can be suspended, lowered and installed(fixed) inside the pit, however, interfering objects such as existing pump, etc. present inside the pit
need to be removed.
For removing interfering objects from inside the pump pit, removal equipment, etc. will need to beinstalled in the limited space inside PCV, and the interfering objects such as existing pump, etc.
present inside the pump pit will need to be removed remotely from the basement floor. The gap
between the inner surface of the pit and the pump is small, and it is not easy to access with tools,
etc. Hence, the method of confirming the status of the target objects by means of images capturedby the camera, and then cutting, etc. and transferring will be studied in detail, and feasibility will beverified by element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly
and Removal Technology]

No.383③ Interfering objects removal from pump pit

Table of Contents⚫
⚫
⚫

Status of studies conducted up to FY2020
Issues, implementation details and results
Consolidation of pre-conditions

⚫
⚫
⚫
⚫
⚫
⚫
⚫

Unit and element test items, and test contents and items to be verified
Scope of simulation in element tests
Study of the remote operation and cutting equipment used in the element tests
Study of tools involved in the work of removing interfering objects from the pump pit
Study of the placement of cameras and lights used in the element tests
Element test results
Issues identified based on the element tests on removal of interfering objects from the pump pit⚫
⚫

Development schedule
Summary©International Research Institute for Nuclear DecommissioningNo.384

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit[Status of studies conducted up to FY2020]⚫ Prospects of feasibility of accessing the pump pit and of the method of installing the submersible pump were seen
based on the element tests.
(Implemented as part of the “Development of technology for the establishment of water circulation systems inside
PCV”)

Portal-type
lifting equipment
門型揚重機

Lowering

ロボット
Robot
arm

アーム

Pump
ポンプ
Lowering
Pump pit

Piping
配管設置
installation
用スタンド
stand

Hose
ホース

ポンプ吊り降ろし
Lifting and lowering pumps

D/W water
D/W取水配管

intake piping

Water intake piping installation(connection) test

Submersible pump suspension test
⇒ The above-mentioned study was conducted on the pre-condition that interfering objects present inside the pump pit
have already been removed.
The method for removing interfering objects from inside the pump pit, which is a pre-condition, will be specified andfeasibility will be verified by element tests.
©International Research Institute for Nuclear DecommissioningNo.385

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit[Issues]• The plan is to install a submersible pump inside the pump pit
located at the lowest location inside PCV in order to control
contaminated water at a still lower location by means of the water
circulation system, however, there are interfering objects such as
existing pump, etc. inside the pump pit, which makes it difficult to
install the submersible pump. Hence technology needs to be
developed for removing interfering objects from inside the pumppit.
[Implementation details]• Actual equipment information, results of the analyses andinvestigations carried out so far on the status of interfering
objects in the periphery of the pump pit for each unit areconsolidated, and the preconditions at the time of interference
removal are studied.
• The method of remotely removing interfering objects such as
existing pump, etc. present inside the pump pit from thebasement floor is studied.
• The remote controlled equipment, cutting equipment requiredfor implementing the removal method considered, are studied.
• Element tests are planned and implemented to verify thefeasibility of the considered technology for removing interfering
objects from inside the pump pit.

Coolingequipment

Insoluble
nuclideremovalsystemSolublenuclideremovalsystem(New/existing)Installation ofsubmersible pumpin the pump pit[Expected outcome]• Presentation of the method of removing interfering objects such as
existing pump, etc. from inside the pump pit.

Illustration after making the D/W water intake lines

Existingpump

Pump pit

Cross section of pump pit (Unit 1)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]No.386③ Interfering objects removal from pump pit[FY2021 Implementation Details]
◼
◼
◼
◼
◼

Compilation of information on the actual site
Compilation of pre-conditions
Study of work steps
Selection of element test items
Study of equipment used

[FY2022 Implementation Details]

◼
◼
◼
◼
◼
◼
◼
◼
◼
◼
◼
◼

Scope of simulation in element tests (Test equipment)
Unit test plan (Test items)
Element test plan (Test items)
Unit and element test items, and test contents and items to be verified
Scope of simulation in element tests (Simulated pump)
Scope of simulation in element tests (Simulated environment: Unit 1, Unit 2)
Study of equipment for remote operation used in the element tests
Study of cutting equipment used in the element tests
Study of tools involved in the work of removing interfering objects from the pump pit
Unit test results
Element test results
Issues identified based on the element tests on removal of interfering objects from the pump pit©International Research Institute for Nuclear DecommissioningNo.387

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼ Consolidation of pre-conditions Summary of pre-conditions➢ The pre-conditions pertaining to the studies conducted during this subsidy project wereconsolidated. The consolidated results are given below.
No.

Items

Target unit, location

Reason1

Status of fuel debris present above the pumppits and inside them
(Scope of removal of existing pump)･ Units 1 - 3 (Case 2: Removal in parts)･ Units 2 and 3 (Case 4: Complete removal[unitized removal])

As locations where fuel debris will not be
retrieved are selected2

Remarks

HeightUnit 2 (2,247[mm])As it was determined that objects that are thetallest (longest) will be difficult to remove

Mass

Assuming Unit 2 (320[kg])As it was determined that objects that are theheaviest will be difficult to remove

DiameterAll units (Φ305[mm])As the dimensions are the same for all units

Pump specifications

3

Pump pit specifications

Units 2 and 3 (1,250(W) x 700(D) x
1,230(H)[mm])4

Pump pit location

・ Pump pit (225°) inside PCV in Unit 1・ Pump pit (202.5°) inside PCV in Units 2
and 3

2 patterns will be
studiedAs it was determined that work will be difficultin the most confined space

The one in which performing work would be
difficult was selected.

2 patterns will be
studied<Selection of No. 4 pump pit location>• The pump pit (225°) inside PCV in Unit 1 is likely to be buried under fuel debris. However, the status of fuel debris is just an estimation. Hence,
the approach that by verifying the viability of work that has a higher level of difficulty, the viability of work with a lower level of difficulty stands
verified, was adopted for selecting the location to be tested this time.
• While selecting the target pump pit, the kerf (level difference), etc. is believed to be a condition that must be considered, but as detailed
information on the kerf, etc. has not been obtained, the level of difficulty was considered as the guideline for selecting the target pump pit.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]No.388③ Interfering objects removal from pump pit◼ Study of work steps a. Overview of work steps➢ An overview of the work steps involved in removing interfering objects from inside the pump pit was studied. The work
steps studied are given below.
[Pre-conditions]• The interfering objects on the access route from the equipment hatch up to the top of the pump pit on PCV first floor
are assumed to have been removed.
• The equipment used for the work is assumed to have been moved to the top of the pump pit on PCV first floor.
Work steps to be tested in the element tests<Overview of work steps> Same for Units 1, Unit 2, Unit 3①

Installation of ancillaryequipment for cutting
an opening in thegrating②

Removal of grating③

Removal of interfering
objects under thegrating④

Removal of interfering
objects present above
the pump pit⑥

Investigation ofdeposits/fuel debris
around the pump pit⑩

Investigation ofdeposits/fuel debris in
the pump pit⑪

Cutting of the pump
(Only Case 2)⑫

Cutting of the bolts
used for installing thepump⑬ Lifting up the pump⑭

Cutting of the bolts
used for installing thepump pit cover⑮

Installation of D/Wwater intake pump⑯

Dike removal⑰⑦

Building of dikes
around the pump pit⑧

Measures for
ensuring visibility
inside the pump pit⑤

Removal ofinterfering objects
present around thepump pit⑨

Cutting of an opening
in the pump pit coverTransfer of interfering
objects©International Research Institute for Nuclear DecommissioningNo.389

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼ Unit and element test items, and test contents and items to be verified
No.

Step / test item

Test contents
The visibility of the submersible camera in adark environment, under water and in a
muddy water environment is verified.

⚫

1⑩ Investigation of deposits/fuel debris in thepump pit・ Handling of cameras/lights for investigation
inside the pump pit

Feasibility of remote operations is verified
by suspending the cameras, lights andcutting equipment from the grating opening,and cutting the pump.

⚫

2⑪ Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit(Case 2)Items to be verified / records

⚫

⚫
⚫
⚫
⚫
⚫

3

⑬ Lifting up the pump・ Slinging the pump4

⑬ Lifting up the pump・ Lifting up the pump (Case 4)

5⑬ Lifting up the pump・ Lifting up the upper part of the pump (Case2)

6⑬ Lifting up the pump・ Moving the pump (D/W first floor)

Feasibility of remote operations is verified
by slinging the pump with the help of a robot.

Reports of element tests⚫
⚫

Setting of conditions so that the target object can be verified (distance,light intensity, etc.)
Conditions are recordedInterference of structures while lifting up and suspending the cameras,
lights and cutting equipment
Placement of the cameras and lights
Adjustment of the installation position of the cutting equipment
Fastening and release of cutting equipment
Cutting of the external pipes of the pump and the shaft using the cutting
equipment (pressure, current value)
Time required for work is recorded⚫
⚫

Interference of structures while suspending the slinging tools
Handling of slinging tools by the robot (grabbing, passing through andinstalling)
Placement of the cameras and lights
Time required for work is recorded

Feasibility of remote operations is verified
by lifting up the pump with the help of robots
and cranes.

⚫
⚫
⚫
⚫

Whether the tension of the wires can be adjusted using a craneInterference with structures while lifting up the pump (Unit 1, Unit 2)
Placement of the cameras and lights
Time required for work is recorded

Feasibility of remote operations is verified
by lifting up the pump with the help of robots
and cranes.

⚫
⚫
⚫
⚫

Whether the tension of the wires can be adjusted using a craneInterference with structures while lifting up the pump (Unit 1, Unit 2)
Placement of the cameras and lights
Time required for work is recorded

The suspension length adjustment tool isinstalled using small robots on the pumpthat has been lifted up by means of thecrane, and the pump is mounted on thetransportation equipment that is placed
within the range of movement of the crane.

⚫
⚫

Handling of the suspension length adjustment tool by the small robot
Interference with structures while mounting the pump on thetransportation equipment
Placement of the cameras and lights
Time required for work is recorded⚫
⚫

©International Research Institute for Nuclear DecommissioningNo.390
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Scope of simulation in element tests (Simulated pump)➢

Simulated pump: The dimensions and mass of the pump in Unit 2 are simulated. Since cutting will be performed
multiple times, the shape of the lower part of the pump is not simulated.

➢

Simulated dummy: A dummy of the same dimensions as the simulated pump is simulated for verifying interference.

➢

Pit cover: Unit 1 and Unit 2 pit covers are simulated.

➢

Pit： Common for Unit 1 and Unit 2.

Unit 2 Drawing of the drain sump pump

Simulated pump for the element tests

Pit cover (Unit 1)

Pit for the element tests

Pit cover (Unit 2)

Layout of the simulation (Unit 1)
Left: Dummy, Right: Simulated pump©International Research Institute for Nuclear DecommissioningNo.391
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼ Scope of simulation in element tests (Simulated environment: Unit 1)➢

The environment in Unit 1 was simulated by restricting the area to the MS pipe rack that interferes at the time oflifting up and moving the pump assuming this is being done in the actual facility, and element tests wereconducted.
Lower surface of the cut
portion of the HVH duct

MS piperack

3170mmGrating
openingArea
restriction

Layout drawing of the Unit 1 PCV first floor at 225°

Upper surface ofthe grating

Bird's eye view of of Unit 1 PCV first floor at 225°

Bird's eye view of of Unit 1 PCV
basement floor at 225°

Area
restriction
Image illustrating the simulation for the element test
(Unit 1 PCV first floor)

Status of the element test (Unit 1 PCV first floor)

Status of the element test
(Unit 1 PCV basement floor)©International Research Institute for Nuclear DecommissioningNo.392
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Scope of simulation in element tests (Simulated environment: Unit 2)➢

The environment in Unit 2 was simulated by restricting the area to the MS pipes and MS pipe rack that interfere at
the time of lifting up and moving the pump assuming this is being done in the actual facility, and setting up asimulation of the pipes, and then element tests were conducted.

MS pipes

MS pipesArea
restriction

Image illustrating the simulation for theelement test (Unit 2 PCV first floor)

Status of the element test
(Unit 2 PCV first floor)

Status of the element test
(Unit 2 PCV basement floor)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]

No.393③ Interfering objects removal from pump pit◼ Study of equipment for remote operation used in the element tests
Small robot

Crane (for element tests)

Robot for suspension

Overview
diagramLegs for moving(detached)Specifications

Explanation

Product developed by Hitachi-GE

Power: Hydraulic pressure
External dimensions: L1503 x W463 x
H575mmMass: Approx. 100kg
Portable Weight: Approx. 7kg/arm

Power: Electric power
External dimensions: L3750 x W920 x
3148mmMass: 490kg
Rated load: 490kg

Power: Hydraulic pressure
External dimensions: L2513 x Φ330 x
H732mmMass： approx. 110kg
Portable Weight： Approx. 20kg

A multi-legged small robot developed in thepast is used. It handles hoisting equipment
and performs slinging operations with bothtask arms.
It carries out work mainly on the PCV firstfloor and basement floor.

It is installed on the grating or the beam ofthe simulated PCV. During the element test,
the scope of movement of the roughter cranethat is planned to be used on the actual site,
is simulated and the work of hoisting anddelivering is verified. (Used in common with
the HVH disassembly)
It carries out work mainly on the PCV firstfloor.

A multi-legged robot developed in the past isused. It assists in handling the hoisting
equipment and the cable hose with task arms.
It carries out work mainly on the PCV
basement floor.

©International Research Institute for Nuclear DecommissioningNo.394

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Study of cutting equipment used in the element tests
Cutting equipment
Motor
Guide

Overview
diagramSpecifications

TargetExplanation

Guide

Stand forsuspension

Deployment
mechanism[Installation position]

Band saw
blade

Feed
mechanism
Band saw
blade

Feed mechanism

Cutting direction[Cutting position]

Power: Electric power / hydraulic pressure (stroke)
External dimensions: 732mm x 370mm x 1140mm(Inside the pit: 560mm x 295mm x 560mm)
Cutting stroke: 190mm (15mm in front / 150mm to be cut /25mm at the back)
Mass: 80kg

Cutting
direction

Shaft
Connection
mechanism[Specifications of the blade]
Saw width: 13mm
Saw thickness: 0.5mm
Pitch: 10/14
Saw length: 1335mm
Material: M42 high speed[Cutting equipment
Band saw part][Cutting conditions]
Motor rotation (rpm): 2700
Drive roller rotation (rpm): 150
Circumferential speed (m/s): 0.96
Current (A) rated 1.9A: 1.5A or lessBlade delivery pressure （MPa): 0.3

Pump: External pipe (FC25), shaft (SUS304)

The cutting equipment is suspended from the grating opening, and is installed inside the pit using the guide. The cutting equipment isdeployed 90° with the help of the deployment mechanism, the blade is delivered with the delivery mechanism and the external pipe andshaft are cut. The stand for lifting up / suspending (including the motor) is positioned over the band saw part.
©International Research Institute for Nuclear DecommissioningNo.395

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼ Study of tools involved in the work of removing interfering objects from the pump pit
Pump slinging tool

Tip of the slinging tool

Overview
diagramSpecifications

Ring on the side
to be inserted

Joint

Suspension length adjustment tool

Wire

Ring on the crane side

Power: None
External dimensions： Φ27.4 x 2626mm
Mass： 0.7kg
Wire： Φ6
Joints： 3
Angle： Total 80° with 3 joints

TargetExplanation

Power: None
External dimensions： 87.2mm x 88mm x 558.5mm
Mass： 3.4kg
Lifting height： 2500mm
Rated load： 0.25ton

Pump

2 slinging tools are passed through the pump opening using a robot, andinstalled on the crane hooks.

The orientation of the pump is changed from vertical to horizontal withthe suspension length adjustment tool and it is lifted up from over thegrating.

©International Research Institute for Nuclear DecommissioningNo.396
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Study of the placement of cameras and lights used in the element tests
Placement of the cameras and lights
Crane: Camera: Lights
Pit

Cameracarriage car

Layoutdrawing

Robot forsuspension

Small robot[PCV first floor
Layout drawing of test equipment]
Common to Units 1 and 2

Bird’s eye cameras: 2
Lights: 1
Details[PCV first floor to basement floor
Bird’s eye view of the test equipment]
Common to Units 1 and 2[Basement floor Layout drawingof test equipment]
Common to Units 1 and 2

Crane cameras: 2

Bird’s eye cameras: 2

Camera carriage car Cameras: 2 Lights: 1

Small robot Cameras: 3

Robot for suspension Cameras: 1

Cameras inside the pit: 2
Lights: 1©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]

No.397③ Interfering objects removal from pump pit◼ Element test results
No. 2 [Step ⑪] Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit (Case 2)
Work
step

⑪-1 Suspending the cutting equipment

Teststatus

Grating
opening

Suspension

Cuttingequipment⑪-2 Installing the cutting equipment
Pump

Small robot
Back
side

Positioning
surfaceCuttingequipment[Suspending the cutting equipment]⑪-3 Verifying the positioning of the cutting
equipment[Position adjustment using small robots]

Front side

[Front side of cutting equipment
Verification of positioning]

Cuttingequipment
Suspension

Indicators

Guide[Suspending the cutting equipment]

Test
results

It was verified that the cutting equipment can besuspended from the grating opening by remote
operation of the crane without any interference, etc.
(Time required for work: 5 min)

Guide

[Installing the cutting equipment]

It was verified that the cutting equipment can beinstalled using the guide without interfering withthe pump by remote operation of small robots.
(Time required for work: 25 min)Positioning
surface[Back side of cutting equipment
Before positioning][Verification after
positioning]

It was verified that the front side of the cutting
equipment had been positioned using cameras. It
was verified that the back side of the cutting
equipment had been positioned by visuallyconfirming the indicator with the cameras. (Timerequired for work: 15 min)©International Research Institute for Nuclear DecommissioningNo.398

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Element test results
No. 2 [Step ⑪] Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit (Case 2)

Work
step

⑪-4 Cutting equipment Before fixing⑪-5 Cutting equipment After fixing

Press cylinder 1
Indicators

Press cylinder 1
IndicatorsPresscylinder 2

Presscylinder 2
Presscylinder 1

Presscylinder 1[Press cylinder 1
Before operation]

Test
status[Press cylinder 1
After operation]

Base section
Common to all units□： 500mm

Press cylinder 2
Indicators
Inside the pit
cover

Press cylinder 2
Indicators[Press cylinder 2After operation]

Set mark

Base
sectionSet mark
Pump[Front view of cutting equipment
Before operation of press cylinder][Top view of the Unit 2 pit
cover cutting equipment][Press cylinder 2
Before operation][Front view of cutting equipment
After operation of press cylinder][Verification of the set markby the camera at the tip of
the robot]

Test
results

It was verified that the cutting equipment can be fixed and set up by operating press cylinder 1 at full stroke and press cylinder 2 up to the set mark by remote operation.
(Time required for work: 25 min)Issues・Measures to be taken if there are foreign material or existing structures inside the pit cover.

©International Research Institute for Nuclear DecommissioningNo.399

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Element test results
No. 2 [Step ⑪] Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit (Case 2)
Work
step

⑪-6 Making preparations for cutting the pump

Lowering

Shaft[Deployment mechanism
Before operation Illustration]

Unit
2

Lowering

Test
status[Deployment mechanism
After operation Illustration]

Deployment
mechanism cylinder[Deployment mechanism
Before operation Submersible camera]

Mechanicalstopper[Shaft connection mechanism
After operation][Shaft connection mechanism
Before operation][Deployment mechanism
After operation Submersible camera]

Indicator
scale
Lowering

Indicator

Shaft connection
mechanism
cylinder[Deployment mechanism
Before indicator operation]

Test
results[Deployment mechanism
After indicator operation][Blade delivery shaft Indicator][Blade delivery shaft Indicator extension]

It was verified that as preparation for cutting, the deployment mechanism can be deployed at 90°, the shaft connection mechanism can be operated and the motor can beconnected in between the gears.
The indicators and mechanical stoppers were verified using a camera from above the pit by operating the mechanisms.
By considering the blade delivery shaft as the scale indicator, the progress in cutting were ascertained from above the pit.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project[1) (2) Development of Disassembly and Removal Technology][Before cutting]<Illustration of
the test>[After cutting]

No.400③ Interfering objects removal from pump pit◼

Element test results
Blade delivery
direction

No. 2 [Step ⑪] Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit (Case 2)
Work
step

⑪-7 Cutting the pump
A pad was installed under thepump but it fell due to its own
resulting in a gap

Outer pipeBand saw
blade[Cutting location: 0mm]
Test
statusUnit
1
Controlitems

Cutting
location

0mm[Cutting location: 40mm]
40mm(Outerpipe part)

77Mm(Outer pipe
+ Shaft)

130mm(Outerpipe part)

150mm(Outer pipe
part)

Motor
rotational
speed (rpm)

2700

2700

2700

2700

2700

Current value
(A)

0.44A
(No load)

0.66

0.95

0.84

0.47

Blade deliverypressure
(MPa)

0.3

0.3

0.3

[Cutting location: 130mm]
Adjustment of the position of
the cameras and lights (manual)[Cutting location: 77mm]

0.3

0.3

[Cutting location: 150mm]

Blade delivery direction
Outer pipe: FC25

Portion to be cut

Shaft: SUS304

Camera - Portion to be cut
200mm
Cameras and lights
Movement of 225mm

10mm

35mm
150mm

[Top view of the installation of cameras and lights][Top view of the cutting
scene]

Test
results

It was verified that the pump can be cut while monitoring the current and blade delivery pressure by remote operation. The pump was possible to be cut while verifying the statusof cutting with the help of the submersible Φ14 CCD camera and indicators.
(Time required for work: 58 min) (without formation of turbidity, before cutting 0.58NTU, after cutting: 9.74NTU)

Issues・Cameras and lights that can follow in accordance with the progress in cutting are required.
・Positioning of cameras so that the edge of the blade of the band saw and the object to be cut are visible.

©International Research Institute for Nuclear DecommissioningNo.401

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Element test results

No. 2 [Step ⑪] Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit (Case 2)
Work
step

⑪-8 Status after cutting the pumpCutting blade

Cut piece (outer pipe)

Pump installationbolts
Cut piece (outer pipe)[After withdrawing the blades]

TeststatusUnit
1⑪

Cutting of the pump
(Only Case 2)[After lifting up the upper
part of the pump]⑫

Cutting of pumpinstallation bolts(Installing/uninstalling the
cutting equipment)⑪

Cutting of pumpinstallation bolts(2 bolts on the cutting
equipment side)

Considerations
Issues[Inside the outer pipe after lifting
up the upper part of the pump]⑬[Removal of pump installationbolts (2 bolts on the cutting
equipment side)]

Lifting up the pump

Proposed revision in work steps⑫

Cutting of the pump
(Only Case 2)(Installing the cutting equipment)

Test
results

Cut piece (shaft)⑬

Cutting of pumpinstallation bolts(Remaining 2)⑭

Lifting up the pump

Uninstalling the cutting equipment

It was verified that the cut piece (outer pipe) comes out wedged between the cutting blades when the blades are withdrawn by remote operation. If the cut
piece is wedged between the blades, the cutting equipment cannot be uninstalled. Hence the work steps need to be revised.
The work steps should be revised, and it should be verified whether the pump in Unit 2 can be cut by removing the 2 pump installation bolts on cutting
equipment side.
・Measures to be taken if the cutting equipment gets stuck.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project[1) (2) Development of Disassembly and Removal Technology][Before cutting]<Illustration of thetest>[After cutting]

No.402③ Interfering objects removal from pump pit◼

Element test results

No. 2 [Step ⑪] Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit (Case 2)
Work
step

Blade delivery
direction⑪-9 Cutting the pump

Upper level:

Φ14CCD camera

Lower level:

Φ55CMOS camera
TeststatusBand saw
blade

Unit
2

Outer pipe
[Cutting location: 73mm][Cutting location: 0mm]
Cutting
position

0mm

Motor rotational speed(rpm)
Current value (A)73Mm (Outerpipe + Shaft)

115mm(Outer pipe
part)

150mm
(Outer pipe
part)

2700

2700

2700

2700

0.44A
(No load)

0.95

0.84

0.47

Control items

Blade delivery pressure
(MPa)

0.3

0.3

0.3

0.3

[Cutting location: 115mm]
Adjustment of the position of thecameras and lights (manual)Portion to be cut

Camera - Portion
to be cut
350mm

Cameras and lights
Movement of
100mm[Cutting location: 150mm]

Φ50CMOSLightsΦ14CCD[Top view of the installation of cameras and lights][Layout drawing of the cameras
and lights](Installed manually)

Test
results

It was verified that the Unit 1 pump can be cut under the same cutting conditions and by delivering the same blade that was used for cutting,while monitoring the current and blade delivery pressure. Also, cutting was performed without any impact such as vibrations, etc. caused by
the removal of the 2 pump installation bolts.
(Time required for work: 55 min) (without formation of turbidity, before cutting 15.57NTU, after cutting: 14.63NTU)

Issues・As the external form of the Φ55CMOS camera is large, it is not suitable for installation inside the pit, hence the size of a highly radiation
resistant camera needs to be reduced.
・Measures to be taken if foreign material, etc. adheres to the lens of the camera and the visibility deteriorates.
©International Research Institute for Nuclear DecommissioningNo.403

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼ Element test results
No. 2 [Step ⑪] Cutting of the pump (Only Case 2)
・ Cutting/grabbing the pump in the pump pit (Case 2)
Work
step

⑪-10 Status after cutting the pump
Cut piece(outer pipe)

Cut piece(outer pipe)

Cut piece(outer pipe)

Cut piece(outer pipe)

Withdrawalof blades

TeststatusUnit
2[After lifting up the upper
part of the pump][25mm withdrawal of blades][75mm withdrawal of blades][Complete withdrawal of blades][Revised work steps]⑪

Cutting of pumpinstallation bolts(2 bolts on the cutting
equipment side)⑫

Cutting of the pumpFirst pump
(Only Case 2)⑬

Cutting of pumpinstallation bolts(Remaining 2)⑭

Lifting up the pump(Installing the cutting equipment)⑮

Uninstalling the cutting
equipment

Steps ⑪ to ⑮ are repeated for the second pump

Test
results

It was verified that the cut piece (outer pipe) can come out wedged between the cutting blades when the upper part of the pump is lifted
up and the blades are withdrawn by remote operation.
It was verified whether it would be possible to manually recover the cut piece (outer pipe) wedged between the blades, and it was foundthat this was possible.
It was verified that a series of operations can be performed by revising the work steps.

Issues・Method of recovering the cut piece (outer pipe) using the robot arms under water.
©International Research Institute for Nuclear DecommissioningNo.404

6. Implementation Items of This Project[1) (2) Development of Disassembly and Removal Technology]<Illustration of the test>③ Interfering objects removal from pump pit◼

[Setting the offset][Pulling out]

Element test results[Removing theoffset]No. 4 [Step ⑬] Lifting up the pump・ Lifting up the pump (Case 4)⑬-1 Setting the offset
Whether the tension of the wires can be
adjusted

Work
Step

[Lifting up]⑬-2 Pulling out the pump from inside
the pit

Robot for suspension

Lifting up

Concrete brackets
Crane chain
Offset tool⑬-3 Removing the offset

Small robot

Moving the lower
portion of the pump[Controlling the rotation of the pump][Offset using the robot for suspension]

Small robot
Crane chain

Wire[Pushing in the pump]

Lower
portion of
the pump

Lifting up

Unit
1

Lifting up

Teststatus[Removing the offset using the robot for suspension]

Crane rotation

Moving the lower
portion of the pump

Suspension

Lifting up

Robot forsuspension[After pulling out the pump][Verifying the tension][Positioning on the basement floor surface]

Test
results

It was verified that the tension can be
adjusted by aligning the hoisting center bymeans of the offset tools using the robot
for suspension and lifting up using thecrane.
(Time required for work: 10 min)Issues・Measures to be taken if the pump is fixed, etc. and cannot be lifted up.

It was verified that the pump can belifted up with the crane and it can bepulled out with the help of small robots.
(Time required for work: 10 min)

It was verified that the pump can be positioned on the basement
floor surface by removing the offset with the help of the robot forsuspension, rotating the crane and suspending the pump.
(Time required for work: 10 min)©International Research Institute for Nuclear DecommissioningNo.405

6. Implementation Items of This Project[1) (2) Development of Disassembly and Removal Technology]<Illustration of the test>[Setting the offset]③ Interfering objects removal from pump pit[Pulling out]

Element test results[Removing theoffset]No. 4 [Step ⑬] Lifting up the pump・ Lifting up the pump (Case 4)
Work
step

⑬-1 Setting the offset
Whether the tension of the wires can be adjusted[Lifting up]⑬-2 Pulling out the pump from inside the pit

Lifting up

Concretebrackets
Crane chain

Moving the lower
portion of the pump[Controlling the rotation of the pump]

Offset tool

Lifting up

Unit 2

Test status

Small robot⑬-3 Removing the offset[Offset using the robot for suspension]

Crane chain
Wire

Small robot

Lower portionof the pump[Verifying the tension]

Lifting up

Lifting up[Pushing in the pump][After pulling out the pump]

Test
results

It was verified that the tension can be adjusted
by aligning the hoisting center by means of theoffset tools using the robot for suspension andlifting up using the crane.
(Time required for work: 10 min)Issues・Measures to be taken if the pump is fixed, etc. and cannot be lifted up.

It was verified that the pump can be lifted up withthe crane and it can be pulled out with the help ofsmall robots.
(Time required for work: 18 min)[Removing the offset using the robot for suspension]

Moving the lower
portion of the pump

Suspension◼

[Positioning on the basement floor surface]

It was verified that the pump can be positionedon the basement floor surface by removing theoffset with the help of the robot for suspension,rotating the crane and suspending the pump.
(Time required for work: 17 min)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project[1) (2) Development of Disassembly and Removal Technology]

No.406<Illustration of the test>③ Interfering objects removal from pump pit◼

Element test results

No. 4 [Step ⑬] Lifting up the pump・ Lifting up the pump (Case 4)
Work
step

[After suspension
length adjustment]⑬-4 Lifting up the pumpLifting up
Teststatus[Suspension length
adjustment][Lifting up]

MS pipes

Controlling the rotation
with the help of therobot for suspension

1978mmSmall robot

Unit[Lifting up the pump]
2 From the basement floor to the

Pump

Hoisting equipment forlower part of pump(Manual installation)

Lifting up

grating opening[Suspension length
adjustment with the help ofsmall robots][Lifting up the pump]
Over the PCV first floor grating

Grating
opening[Pump lifted up completely]

Test
results

It was verified that the pump can be lifted up by remote operation of the crane without any interference. The pump rotates when it is being
lifted up. It was verified that the rotation of the pump can be controlled by means of the robot for suspension. It was verified that in order toavoid the MS pipes in Unit 2, when the pump is halfway through the grating opening, it can be tilted using the suspension length
adjustment tool and can then be lifted up through the grating opening.
(Time required for work: 58 min)Issues・Studies are required for confirming that the hoisting equipment can be installed on the lower portion of the pump by remote operation,
・The chain of the suspension length adjustment tool is long and hence the work requires time.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project[1) (2) Development of Disassembly and Removal Technology]

No.407<Illustration of the test>[Loading the pump]③ Interfering objects removal from pump pit
Element test results

No. 6 [Step ⑬] Lifting up the pump・ Moving the pump (D/W first floor)
Work
step

[Moving the pump]⑬-5 Moving the pump⑬-6 Loading the pumpWith the help ofsmall robots

Pump

Lifting up

MS pipes[Avoidinginterferences]

With the help ofsmall robots

Pump

Test
statusUnit
2[Lifting up the pump][Avoiding interfering objects][Suspending the pump][Camera at the tip of the crane jib]With the help ofsmall robots

With the help ofsmall robots[Controlling the rotation of the pump]

Suspension◼

[Rotating the crane]

Dimensions oftransportation cart

[Pump completely suspended][Pump completely suspended]

Test
results

It was verified that the pump can be moved by lifting it up with acrane that is remotely operated, by rotating the crane while thepump is in a horizontal position, or avoiding the interfering
objects with the help of small robots, or controlling the rotation of
the pump. (Time required for work: 30 min)Issues・The small robots need to be frequently moved in restricted spaces and cable needs to be routed every time the robots are moved.

It was verified that the pump can be loaded within the dimensions of
the transportation cart with the help of small robots by suspending thepump using a crane that is remotely operated.
(Time required for work: 10 min)©International Research Institute for Nuclear DecommissioningNo.408
6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼
No.

Issues identified based on the element tests on removal of interfering objects from the pump pit (1/2)
Step / test item

IssuesCountermeasures (Considering the actual facility)

・ Measures to be taken if there are foreign ・ Verifying the status of field investigation.
material or existing structures inside the pit cover.
・ Considering a design that enables pressing eveninside the pit.
・ Ensuring of visibility to the extent that the ・ Considering a waterproof and small size pan tilt
cameras and lights can follow in accordance with mechanism for the cameras and lights.
the progress in cutting inside the pit.
・ Necessity to position the cameras so that the ・ Mounting the cameras and lights inside the cuttingedge of the blade of the band saw and the object to equipment.
be cut are visible.

1・ Measures to be taken if the cutting equipment⑪ Cutting of the pump (Only Case 2)
gets stuck.
・ Cutting/grabbing the pump in thepump pit(Case 2)・ The outer form of a highly radiation resistantcamera is large and is thus difficult to handle inside
the pit. (Φ55CMOS)

・ Mounting the cutting mechanism of the blade inside
the cutting equipment.
・ Design so that the blade gets ripped apart due to thethrust of the withdrawal cylinder.
・ Selecting an appropriate radiation resistant camera
after verifying the dose through field investigation.
・ To be accomplished through a combination of time
management and replacement of cameras.

・Measures to be taken if foreign material, etc. ・ Coating the lens.
adheres to the lens of the camera and the visibility ・ Designing the equipment so that the foreign material
deteriorates.
can be removed by spraying water.

2⑬ Lifting up the pump・ Slinging the pump・ Method of recovering the cut piece (outer pipe) ・ Designing so that the robot arm can be operatedusing the robot arms under water.
under water.
・ Considering radiation resistance and water resistanceof the arm camera.
Measures to be taken if there is no space for the ・ Verifying the status of field investigation.
slinging tool to pass due to foreign material in the ・ Considering alternative measures. (Proposal to use apump opening part.
lifting magnet, to slip on a flange, etc.)©International Research Institute for Nuclear DecommissioningNo.409

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit◼

Issues identified based on the element tests on removal of interfering objects from the pump pit (2/2)

No.

Step / test item

IssuesCountermeasures (Considering the actual facility)

・ Measures to be taken if the pump is fixed, etc. ・ Verifying the status of field investigation.
and cannot be lifted up.
・ Considering alternative measures. (Proposal to
cutting the pump base, etc.)

3⑬ Lifting up the pump・ Lifting up the pump (Case 4)

・Studies are required for confirming that the
hoisting equipment can be installed on the lower
portion of the pump by remote operation. (Thistime the shape of the lower portion of the pumphas not been simulated)
・The chain of the suspension length adjustment
tool is long and hence the work requires time.

・ The simulated hoisting equipment is designed
according to the actual facility.

・ Reducing the length of the chain.
・ Designing equipment that is motor operated.
・ Considering installation of a main winding hook andan auxiliary winding hook mechanism on to the roughter
crane assuming the actual facility.

4・ Measures to be taken if the pump is fixed, etc. ・ Verifying the status of field investigation.
⑬ Lifting up the pumpand cannot be lifted up.
・ Considering alternative measures. (Proposal to cut
・ Lifting up the upper part of the pump
the pump base, etc.)(Case 2)

5

⑬ Lifting up the pump・ Moving the pump (D/W first floor)

6

Other

・The small robots need to be frequently moved in ・ Designing equipment in which a task arm is installed
restricted spaces and cable needs to be routed on the transportation cart.
every time the robots are moved.
・ Considering reduction of size of the cable recovery
equipment.
・ Measures to be taken against dust dispersion if ・ Designing water sprinkling equipment.
the pump falls.
・ Acquiring data on dust dispersion©International Research Institute for Nuclear DecommissioningNo.410

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit: Planned: Planned (after revision)*: Actual◼ Development Schedule
FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

FY202212

1

2

3Interim Report
▼

4

5

6

Interim Report
▼

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final
report
▼1. Conceptual study

2. Element test plan

3. Test preparation /Testmanufacturing oftest equipment
4. Element tests

5. Summary

Remarks* The plan was revised to reflect the study progress status and the results of element tests.

©International Research Institute for Nuclear DecommissioningNo.411

6. Implementation Items of This Project [1) (2) Development of Disassembly and Removal Technology]③ Interfering objects removal from pump pit: Summary➢ The status of fuel debris inside the pump pit, specifications of pump to be removed,
specifications of pump pit, and its location were studied and consolidated in FY2021
as preconditions for removing interfering objects from inside the pump pit. The work
steps involved in removing interfering objects from inside the pump pit were studied,and test items were selected.
➢ The simulated pump and pump pit, equipment and tools, etc. to be used in theelement tests were studied, the work steps were substantiated and the element test
plan (consolidation of items to be verified, test contents, etc.) was formulated.
➢ It was verified through element tests that the pump can be cut, lifted up, etc. by
remote operation, and the feasibility of the method of removing interfering objects
from the pump pit was verified as well. Issues in application to the actual facility wereidentified and reflected into the equipment design for the actual facility.

©International Research Institute for Nuclear DecommissioningNo.412

6. Implementation Items of This Project1) Development of side access method(3) Advancement and development of retrieval methods① Remote controlled tip tools for retrieval
In parallel with the study of prospective methods for further increasing the scale of retrieval of fueldebris and reactor internal structures, evaluation of the throughput is being carried out as well. For
enhancing the throughput of the side access method, it has become necessary to consider
optimization of the positioning of the tip tools, grabbing of the target object, replacement of the tip
tools, etc. during fuel debris processing and collection work, and carry out related development.
Various techniques have been studied during the development carried out in the past related tothe tip tools of the remote controlled equipment used for fuel debris retrieval anddisassembly/removal of reactor internal structures, however, tip tools suitable for optimization
including the technologies available on the market, will be investigated and consolidated.
In addition, typical techniques pertaining to the tip tools and operation systems (interference
avoidance and control system, etc.) that can be used for works that need to be optimized andimproved, will be selected based on the requirements for on-site application, and tip tools andoperation systems will be test manufactured for on-site use by making improvements intechnologies available on the market or by developing new technologies. With the help of these test
manufactured tip tools and operation systems, the procedures for processing fuel debris andcollecting it in unit cans, operability of the tip tools, efficiency, etc. will be verified through tests
using mock-ups (appropriate partial models or scale models are permissible as well) considering themechanical properties, etc. of the items to be processed such as fuel debris, etc., interfering objects
such as structures, etc. inside PCV, and the viability of a series of operations will be verified. Also,
the actual data on the work procedures will be acquired and organized, to create data for evaluating
the throughput.

©International Research Institute for Nuclear DecommissioningNo.413
6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval

Table of Contents(1) Development results achieved so far and correlation with this project(2) Background and purpose of this research(3) Goals(4) Implementation items, their mutual correlation, and correlation with other research(5) Implementation items(6) Development schedule(7) Summary©International Research Institute for Nuclear DecommissioningNo.414
6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(1) Development results achieved so far and correlation with this project[Advancement of fundamental technology (Implemented
in FY2017-18)]• Development of access equipment➢ Combination test of access route and robot arm✓ Installation of access route✓ Guiding the robot arm inside the pedestal
Combination test of rail
and arm

Combination test of rail
and arm[Further increasing the scale of retrieval (Implemented in FY20192020)]• Review of side access method for on-site application➢ Study of fixed rail method(Downsizing of access equipment ⇒ Reduction in cell height)• Development of suction and collection system for granular fueldebris[Implemented in this project]• Study and element tests on tip tools, remote operation
support systems• Acquisition of data for throughput evaluation

Study of fixed rail
methodSuction and collectionof granular fuel debris©International Research Institute for Nuclear DecommissioningNo.415
6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

Exce① Remote controlled tip tools for retrieval(1) Development results achieved so far and correlation with this project[Status of development carried out so far]
• Processing methods suitable for items to be collected from inside the PCV were investigated.
• Processing element tests were implemented on the processing technology believed to have good prospects,
from among the processing methods investigated.
• Procedures for collecting structures, fuel debris were studied.
• The fuel debris retrieval throughput was estimated based on the results of the processing element tests, resultsof the accessibility test, results of the desk study, etc.
Examples of the processing methods investigated in the past(excerpts from FY2019-20 reports)
Handling of avariety of fueldebrisProcessing
speed

Accessibility(small head)

Heat input

Fume emission(dispersion in
air)

Quantity of scrap
produced (dispersion
in water)Downsizing ofutilities

Need forsupplyPast processing element tests

Core boring
Circular saw
Wire saw
Band saw(reciprocating saw)
Ultrasonic core drill

Cutter (shears)
ChiselLaser
Plasma arc
Plasma jet
Gas

FY2014:
・Core boring
・Laser gouging
・Plasma・AWJ
・Laser (shaving)
FY2015-16
・Core boring
・Laser gouging

FY2017-18
・Chisel・Ultrasonic core boring
・AWJ
・Laser・Circular cutter
・Wire saw
FY2019-20
・Hydraulic cutter
・Grindstone
・Tip saw
・Wedge and shim・Ultrasonic core boring

Milling©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.416① Remote controlled tip tools for retrieval(1) Development results achieved so far and correlation with this project[Status of development carried out so far]
Past processing element tests (Example)
Year20152016

Processing
methodCore boring

Simulation

Status of test (Installed in the machine tool,etc.)

・SUS304
・Alumina

Processing speed
2.86[mm/min]・Outer diameter of cutter:
Φ66mm

Alumina
Alumina

2.5[kg/h]
・FY2017-18 Estimation
results

20172018

Chisel・Simulated
MCCI

The surface after crushingis by a large gray with very
few gaps

CracksProcessing
point

36.7[kg/h]

HoleChisel B
The whitish portion is the
portion that was unable tobe crushed

Chisel A

20172018

Circular cutter

・SUS304
・Zirconia

Circular cutter

750[mm2/min]
・Depth: 1.5mm
・Length: 100mm
・Time: 0.2min

Test
piece

©International Research Institute for Nuclear DecommissioningNo.417
6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(1) Development results achieved so far and correlation with this project[Issues]• With the current processing speed, the target retrieval period of 10 years is exceeded.
• The throughput is estimated based on the processing time obtained through the processing test using mainly machine
tools, but the processing time is likely to extend when processing work is carried out using tip tools mounted on remotecontrolled equipment that lacks rigidity.
• The throughput for a lot of work (positioning the tip tools, etc.) other than processing work is estimated assuming the timerequired for work, and hence its accuracy needs to be improved.
[Implementation details]• Study of throughput improvement measures➢ Study of procedures for collecting structures, fuel debris inside PCV➢ Study of processing methods➢ Enhancement of equipment operability• Obtaining processing time considering the specifications of the access equipment➢ Manufacturing and processing tests of the tip tools that meet the specifications of the access equipment➢ Acquisition of data for throughput evaluation such as processing time, life of the blades, etc.
• Enhancement of safety and work efficiency by developing a remote operation support system for reducing the operator
load while operating the manipulator➢ Development of a remote operation support system that creates the route for avoiding interfering objects.
➢ Verification of the feasibility of work by means of simulation, scale model mock-ups➢ Acquisition of data for throughput evaluation (obtaining improvement effects resulting from accuracy improvement andoptimization)[Expected outcome]• Verification of the methods for disassembly and removal of structures inside PCV, andthe procedures for processing and collecting fuel debris.
• Acquisition of data for throughput evaluation.
©International Research Institute for Nuclear DecommissioningNo.418
6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(1) Development results achieved so far and correlation with this project[Flow of studies]
Study of throughput improvement measures

Tip tools

Operation system(Interference avoidancecontrol system)

Technical research on tip tools

Conceptual study of the operation system

Operation system software development
Conceptual study of the method of retrieving
structures and fuel debris from inside PCV

Operation system simulation verification

Tip tools element tests planning
Operation system element tests planning
Designing and maufacturing of tip
tools and test equipment for theelement tests

Tip tools element tests(Processing tests for throughput evaluation)
Interfering objects and fueldebris processing time

Designing and manufacturing of operation systemtest equipment

Operation system element tests(Series of operations for throughput evaluation
using the scale model mock-up)

Acquisition of data for throughput evaluation

Time required for manipulator work
(Time required for moving andpositioning)©International Research Institute for Nuclear DecommissioningNo.419

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(2) Background and purpose of this research (Tip tools)✓ Reasons for this research• So far, the processing methods suitable for the items to be collectedfrom inside the PCV have been investigated, processing tests havebeen implemented, and the throughput has been estimated based on
the results.
• The throughput is estimated based on the processing time obtained
through the processing test using mainly machine tools, but theprocessing time is likely to extend when remote controlled equipmentthat lacks rigidity is used.
• Therefore, tip tools with specifications suitable for the current remotecontrolled equipment (access equipment) will be manufactured, andprocessing tests will be conducted to improve the accuracy of theprocessing time.

Telescopic dual motoroperated arms

Fixed rail type dual motoroperated arms

Alumina
AluminaCircular cutter

Test piece

Status of past processing tests

Fixed rail type single
hydraulic arm

Remote controlled equipment (access equipment) assumed at present©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.420① Remote controlled tip tools for retrieval(2) Background and purpose of this research (Tip tools)✓ Expected outcome of this research, reflection destination, and contribution of theoutcome[Expected outcome]• Applicability of the tip tools to the actual equipment, issues and response
measures• Data for throughput evaluation➢ Processibility➢ Processing time
➢ Life of the blades• Required specifications of the remote controlled equipment (Access equipment)➢ Processing reaction force (required tip tool pressing force), etc.
[Reflection destination]• Designing of remote controlled equipment• Evaluation of throughput[Contribution]• Enhancement of specificity of the fuel debris retrieval method• Evaluation of the fuel debris retrieval period©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.421① Remote controlled tip tools for retrieval(2) Background and purpose of this research (Operation system)✓ Reasons for this research• The work of removing interfering objects and retrieving fuel debris will
be carried out while avoiding obstacles in a confined space such asthat of the PCV. A manipulator with a redundant degree of freedom(having multiple joints with 7 shafts or more) is effective for the work.
• However, remotely operating the manipulator with a redundant degreeof freedom while avoiding obstacles under conditions with limited
visibility puts too much load on the operator, and the manipulator is
likely to collide with obstacles.
• Hence, the load on the operator is planned to be reduced by means ofan “operating system that supports remote operation” thereby
enhancing work efficiency.

Illustration of the work of removing
interfering objects in Unit 3✓ Expected outcome of this research, reflection destination, and contribution of the outcome[Expected outcome]: Automation of obstacle avoidance by the manipulator[Reflection destination]: Development will be carried out assuming the outcome will be used in the remotecontrolled robot for fuel debris retrieval, but application to various other works and robots in the future will be
aimed for. (The environment model and the robot model will be changeable)[Contribution]: Enhancement of work safety and efficiency can be expected.*• With the operational support resulting from the previous research “Development of remote operation support methods in environments with low
visibility and narrow spaces” implemented in FY2019-20, there has been a reduction of approx. 90% in the time required for manual operation byveteran operators, and a reduction of approx. 80% in the time required for creating teaching data. With the current development, this will be
implemented and enhanced further.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.422① Remote controlled tip tools for retrieval(3) Goals (Tip tools)✓ Requirements from the reflection destinations• Processing tests with the processing conditions extensively considered as parameters
Processing tests will be conducted by extensively considering the processing conditions
such as pressing force, etc. as parameters, so as to be able to apply the outcome tovarious equipment without limiting it to the specific access equipment.
• Throughput improvement
Tests for throughput improvement will be conducted during the process tests as well.
✓ Goals based on the above-mentioned requirements• Processing tests will be conducted not only for testing the pressing force (motor-operated
arms 150kg, hydraulic arm 2ton) of the access equipment currently being assumed, butalso for testing the low pressing force assuming smaller access equipment. The
processibility will be verified and data for throughput evaluation will be acquired.
• Tests will be conducted by increasing the current core boring size of Φ66mm in order toreduce the processing time for block fuel debris (fuel debris accumulated at the pedestal
bottom) which comprises a major portion of the throughput.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Developmentof Retrieval Methods]

No.423① Remote controlled tip tools for retrieval(3) Goals (Operation system)✓ Requirements from the reflection destinations• Reducing the load on the operator
While determination of status, adjustment of the movement speed will be performed by theoperator, complex selections, procedure studies, and wide range monitoring will be left to thesystem as far as possible so as to reduce the load on the operator.
• Expandability
The application will not be limited to specific equipment. The tools will be deployed to various
other works and equipment in the future. Also, they will be linked to the integrated
management system that is responsible for planning, management and keeping records
during decommissioning.
✓ Goals based on the above-mentioned requirements• Tests will be conducted with mock-ups simulating the inside of the pedestal in Unit 3 using thetest manufactured operation system, the procedures involved in grabbing, cutting andtransferring interfering objects and collecting fuel debris in unit cans will be verified, and viabilityof a series of operations will be confirmed. Also, the actual data on the work procedures will beacquired and organized, to create data for evaluating the throughput.
• Case studies on the operation system application conditions, assumed issues, etc. will beconsolidated as an input for planning the procedures for disassembly and removal.

©International Research Institute for Nuclear DecommissioningNo.424
6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(4) Implementation items, their mutual correlation, and correlation with other research (Tip tools)✓ Implementation items of this research• Study of throughput improvement measures➢ Analysis of past throughput estimations➢ Study of the contents to be implemented in element tests• Technical research on tip tools➢ Consolidation of results of past investigations on processing methods➢ Investigation of new processing methods• Conceptual study of the method of retrieving structures and fuel debris from inside PCV➢ Study of procedures for collecting structures, fuel debris➢ Study of methods for processing structures and fuel debris• Element test planning➢ Conceptual designing of tip tools for the actual equipment➢ Study of test items and test method• Designing and manufacturing of tip tools and test equipment for the element tests➢ Designing and manufacturing of test equipment• Tip tools element tests➢ Processing tests using the tip tools➢ Evaluation of processing test results (including evaluation of throughput improvement
measures)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.425① Remote controlled tip tools for retrieval(4) Implementation items, their mutual correlation, and correlation with other research (Tip tools)✓ Correlation between implementation items
Study of throughput improvement
measures

Technical research on tip tools

Conceptual study of the methodof retrieving structures and fueldebris from inside PCV

Element test planning

Designing and maufacturing of tip
tools and test equipment for theelement tests

Tip tools element tests
Operation system
Data for throughput evaluation✓

Correlation with other research (Input and output information)• The processing limit will be studied while controlling criticality andsharing information.
©International Research Institute for Nuclear DecommissioningNo.426

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(4) Implementation items, their mutual correlation, and correlation with other research (Operation system)✓ Implementation items of this research• Test manufacturing of the operation system, verification of viability of a series of works by means of mockup tests• Acquisition of actual data on the work procedures, creation of data for throughput evaluation✓ Correlation between implementation items, correlation with other research (Input and output
information)• Conceptual study on utilization of data is underway together with the Fuel debris retrieval
monitoring/support/integrated management WG.
• The model has been manufactured based on the 3D damage model of the inside of the Unit 3 pedestal.
(2) Remote operation
support system fordecommissioning(Operation management )Development ofwork plan
Integrated
management support

Work historyWork
authorization

Operation history

Designing ofequipment andwork
Risk management
historyThis research(3) Decommissioning
work history recording
system

CRD housing(1) Environmental
model
Virtual 3D of theinside of the PCV

CRD housing support
Pedestal
opening

CR guide tube

Processing
information
Equipment
information
Sensorinformation

Continuous monitoring of theenvironmental parameters(temperature, pressure, dose rate,etc.)
Detailed
investigation,
analysis andevaluation of design
information

Modification of theactual time in theenvironmental model

CRD rail

Platform rotating rail

Height of worker
access port:
approx. 2m

Changes on the site

Implementationof work on thesite

Height ofpedestal
opening:
approx. 3m

Measurement andkeeping records ofthe retrieved items

Activities inside andoutside the PCV

Data utilization proposal by the Fuel debris retrieval
monitoring/support/integrated management WG

Solid line

Main flow of data

Dashed line

Flow of data due to impact

Double line

Coordination between systems

Deposits
Rotating rail support

Pedestal inner diameter:
Approx. 5m

Worker access
port

Platform frame

3D damage model of the inside of the pedestal
reproduced based on the images from the Unit 3
Internal Investigation conducted in July 2017

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.427① Remote controlled tip tools for retrieval(4) Implementation items, their mutual correlation, and correlation with other research (Operation system)✓ Development results achieved so far and correlation with this project
While carrying out research on obstacle avoidance by the multi-jointed (articulated) manipulator,
its versatality and practicality are being enhanced as well.
Development project

Details

Development of technology for remote decontamination inside R/B(FY2013 - FY2014)

A technique for generating self motion was developed as a method for remote intuitive maneuvering of the manipulator with aredundant degree of freedom and its effect was verified.

Advancement of fundamental technology for retrieval of fuel debris andinternal structures (FY2017-FY2018)“Development of a technique for planning the motion of a multi-degree of
freedom robot considering avoidance of interference with the environment”

During the work of welding the cell adapter to the PCV wall surface in “one stroke”, a route following the welding line while
avoiding interfering objects was created and the effectiveness was verified by mock-up welding tests.

Development of Technology for Further Increasing the Scale of Retrievalof Debris and Reactor Internal Structures (FY2019-FY2020)“Development of technique for remote operation support in environmentswith low visibility and confined spaces”

The trajectory for reaching the goal while avoiding obstacles was created automatically using a computer, the technology(trajectory planning) for setting the replay speed through joystick operation by the operator was developed, comparative
verification with past operating techniques (manual operation, teaching) was carried out and the effectiveness was verified,
for the purpose of interference removal work by means of a dual arm type manipulator. → The details of the research havebeen posted under Advanced Robotics in the Journal of the Robotics Society of Japan(Topic: A comparative study of manipulator teleoperation methods for debris retrieval phase in nuclear power plant
decommissioning)This Project (FY2021-FY2022)“Remote controlled tip tool for retrieval”

A technology will be developed for making it possible to carry out fuel debris retrieval work safely and in a short time, wherein
when the dual arm type manipulator is being positioned for “grabbing”, “cutting”, etc., or if there is a gap between the 3Dmodel and the actual condition, the gap will be corrected then and there and the route for avoiding obstacles will be
regenerated.

Self motion (FY2013-FY2014)

Planning for movement over the welding route (FY2017-FY2018)

Dual arm type manipulator route planning (FY2019-FY2020)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.428① Remote controlled tip tools for retrieval(5) Implementation items (Tip tools)✓ Objective• Processing tests will be conducted using tip tools with specifications suitable for the current
remote controlled equipment (access equipment), data for evaluating the throughput such asprocessing time, etc. will be acquired, and the accuracy of the data for throughput evaluation
will be improved.
✓ Project Goals• Processing tests will be conducted using tip tools with specifications suitable for the current
remote controlled equipment (access equipment), whether or not processing is possible will beverified, processing time will be measured, and issues will be identified.
• Processing tests will be conducted not only for testing the pressing force (motor-operated arms
150kg, hydraulic arm 2ton) of the access equipment currently being assumed, but also for
testing the low pressing force assuming smaller access equipment. The processibility will beverified and data for throughput evaluation will be acquired.
• Tests will be conducted by increasing the current core boring diameter of Φ66mm in order toreduce the processing time for block fuel debris (fuel debris accumulated at the pedestal
bottom) which comprises a major portion of the throughput.

©International Research Institute for Nuclear DecommissioningNo.429

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(1) Study of throughput improvement measures• The throughput estimations from the “1F-3 Fuel Debris Retrieval Method Conceptual Study Contract (Part 3)” outsourced to
TEPCO in FY2021, were analyzed.
(This throughput is a result of revising the throughput estimated in the FY2017-18 Subsidy Project, during the project outsourced
to TEPCO.
➢ Removal of interferences outside the pedestal: 2,018 hours (84 days)➢ Removal of CRD rail:
63 hours(3 days)➢ Removal of CRD exchanger:
1,543 hours (65 days)➢ Removal of CRD housing:
4,717 hours (197 days)➢ Collection of granular fuel debris: 2,506 hours (105 days)➢ Collection of small pebble-shaped fuel debris:➢ 3,560 hours (149 days)➢ Collection of block fuel debris: 30,282 hours (1,262 days) ･･･Of which the processing time was 17,394Hr (725 days)• In this development, studies and processing tests will be conducted aiming for reduction in processing time for block fuel debris(fuel debris accumulated at the pedestal bottom) which comprises a major portion of the above-mentioned throughput.
➢ Technical study of new processing methods that have the potential of enhancing processing speed➢ Increasing the current core boring rotational speed to 150rpm(Since the payload of the robot arm is based on the pressing force of the current core boring, the pressing force is consideredcurrent).
➢ Increasing the current core boring diameter of Φ66mm (The test will be conducted with a diameter of Φ65mm which is thesame as that used in past tests, and a diameter of Φ130mm aiming for an increase in throughput by reducing the processing
frequency).

Carrying in/out
of equipment

Tool
positioning(Example) Throughput of interference
removaloutsidethe pedestal
Cut pieces
Replacement
Cut pieces left

Processing

behindcollected incontainersof blades
within the cell

Unit: Hours
Transfer ofcollection
containers

Total(84 days)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.430① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(2) Technical research on tip tools• So far, many processing methods suitable for the material and shape of items to be collected were investigated,
and their applicability was studied.
• SUS304 and ceramic are assumed to be mixed in fuel debris.
• The processing method for fuel debris accumulated at the bottom of the pedestal, which comprises a major
portion of the duration for fuel debris retrieval at present, was studied once again. Chisel and core boring wereidentified as applicable processing methods.
Processing method for fuel debris accumulated at the bottom of the pedestal
Processing method

Applicability

Evaluation(1) Processing everything with ablade to form swarf

・ Can be processed.
・ Will require time.

△： Processing requires time(2) Processing everything with achisel to form gravel

・ Whether or not processing is possible depends on the properties of the items to beprocessed.
・ If the item is brittle enough to be processed, processing is fast.

〇： Processing is fast(3) Core boring・ Can be processed.
・ A method of cutting out the core horizontally is required.

〇： Excellent processibility amongst the potential
methods for processing hard layers ⑴, ⑶ to ⑹(4) Cutting out by making
intersecting cuts with a circular
cutter・ Can be processed.
・ As work progresses to the second and third layer, the shape of the surface
becomes complex and hence processing becomes difficult.

△： Processing is difficult from the second layer
onwards(5) AWJ (Abrasive Water Jet）

・ Can be processed from the viewpoint of material.
・ Processibility of shapes that cannot be penetrated, management of large quantityof abrasive are issues.

△： Processing is difficult in the case of shapes thatcannot be penetrated.

⑹ Laser・ Can be processed from the viewpoint of material.
・ Processibility of shapes that cannot be penetrated, management of dross areissues.

△： Processing is difficult in the case of shapes thatcannot be penetrated.

(7) Plasma

・ Non-conducting ceramic cannot be processed.

x： Cannot be processed(8) Gas・ SUS304, ceramic cannot be processed as oxidation reaction is used.

x： Cannot be processed©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.431① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(3) Conceptual study of the method of retrieving structures and fuel debris from inside PCV[Tip tools development procedure]
Procedures for collecting structures andfuel debris
・ Study of collection method

Study of collection procedures and collection method depending on theposition, shape and properties of the structures and fuel debris

Identification of the functions required of
the tip tools
・ Conceptual designing

Identification of required functions, and conceptual designing of tip tools
・ Dimensions and mass that will enable the remote access equipment to guide
・ Function for recognizing the surrounding environment, visibility function for
positioning the tool on the object to be processed
・ Operation system for reducing the load on the operator
・ Function for processing structures and fuel debris
・ Dust measures during processing

Identification of items that needtechnical development from among
the required functions

Technical development (Element tests)

Tip tools for the actual equipment
・ Verification using the accessequipment

Identification of items that need technical development
・ Technology concerning the method (Cutting method, positioning,processing time, etc.)
・ Control technology (Automatic, semi-automatic, support, etc.)
・ Safety measures (Dust, fire, overall system, etc.)
Technical development through testing and analysis: Scope of element tests
・ Processing technology
・ Operation system for reducing the load on the operator
・ Dust measures during processing

Verification of viability of a series of operations using equipment anticipating
the actual equipment
・ Ability to access and be positioned on the object to be processed
・ Processing performance
・ Impact of the rigidity of the access equipment©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.432(3) Conceptual study of the method of retrieving structures and fuel debris from inside PCV[Study of procedures for collecting structures and fuel debris]• Overview of the current proposal
Interference removal using telescopic dual motor-operated
arms (Outside the pedestal)Interference removal using telescopic dual motor-operated
arms (Inside the pedestal)(Outside the pedestal)(Inside the pedestal)Interference removal using telescopic dual motor-operated arms

Changing to a fixed rail
Chisel B

Interference removal using dual motor operated arms

Chisel A

Interference removal using
dual motor operated arms

Suction of granular fuel debris using dual motor operated arms

Suction of granular fueldebris using dual motor
operated arms

Block fuel debris
processing using dual
motor operated arms

Current core boring dimensions: Φ66mm x H100mm (342cm3)
Processing limit of 1 round: 16 cubic cm (4096cm3)

Block fuel debris processing using dual motor operated arms

Block fuel debris processing using single hydraulic arm

Making a holeat the centerCore boring

Core cutting

Block fuel debris processing using single hydraulic arm©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.433① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(3) Conceptual study of the method of retrieving structures and fuel debris from inside PCV[Processing method depending on the items to be collected]• Processing methods depending on the location and material of the items to be collected were studied and thefollowing processing methods were selected.
Processing methods depending on the items to be collected
Items to be collected

Processing method

Reason for selection•

Interfering objects(Structure)

Circular cutter

Granular fuel debris

SuctionBlock fuel debris(Brittle portion)

Block fuel debris(Hard portion)••

Granular fuel debris does not need to be processed, and as it is difficult to holdsuch small debris, suction was selected from the perspective of collection speed.

•

The chisel which has a faster processing speed was selected for the brittle portionof fuel debris accumulated at the pedestal bottom, from among the processing
methods studied in the element tests. It is assumed that one of the dual motoroperated arms will process the debris with the chisel and the other will collect theprocessed pieces.

•Core boring was selected for the hard debris from the fuel debris accumulated at
the pedestal bottom, which cannot be processed with a chisel, based on the resultsof the aforementioned studies on processing methods. As this debris is hard and is
expected to require great force, it is assumed that the processing will be carried out
with a single hydraulic arm.

ChiselCore boring(Including core cutting)

As the interfering object needs to be held and cut while making sure it does not fall,
it is assumed that one of the dual motor-operated arms will hold the piece and theother will cut.
The circular cutter that is compatible with various shapes was selected as themethod for cutting the interfering objects, from among the processing methods
studied in the element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(3) Conceptual study of the method of retrieving structures and fuel debris from inside PCV[Study of methods for processing structures and fuel debris]• Study of methods for collecting the core at the time of core boring
Core collection method〇: Merits

x： Demerits

Characteristics

Core boring from 2 directions〇: The reactor core does not need to be cut (Only 1 type of tool is required).
X : The reactor core remains inside the tool and is difficult to retrieve.
X : As work progresses to the second and third layer, the shape of the surface becomes complex andhence processing becomes difficult.

Making a hole at the center bymeans of core boring for insertingthe circular cutter, and then cutting
the core with the circular cutter〇: Good processibility at the second and third layer.
〇: Reactor core can be easily removed.
X : Core cutting and core collection tools other than the core boring tools are required.

Stroke ①

No.434

Stroke ②

Adopted based on the processibility at the second and third layer

Stroke ③

Stroke ①
Stroke ②
Top view
Making a hole bymeans of core boringby sliding slightly
offsetTop view Stroke ④

Cutting blade

Bulk to be
removedLateral view
Lateral view

Bulk to be removed

Core boring from 2 directions(Making a hole for inserting the circular cutter by means ofcore boring)

Hole for inserting the circular cutter made bymeans of core boring by sliding slightly offset(Core cutting using a circular cutter)

Making a hole at the center for inserting the circular cutter ⇒ cutting the core
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.435Excer(4) Element test plan
[Purpose]• Verification of processing capability as a tip tool
• Tip tools with specifications suitable for the current remote controlled equipment (access equipment) will bearranged and processing tests will be conducted using those tip tools for verifying whether or not processing ispossible, measuring the processing time, and identifying issues.
➢ Dual motor-operated arms
✓ Payload: 150[kg]✓ Tip tool dimensions: W600×D500×H550[mm]➢ Single hydraulic arm✓ Payload： Facing down： 2[ton], Facing up: 1 [ton]✓ Tip tool dimensions: W600×D500×H750[mm]Dual motor-operated arms

Single hydraulic arm

Study of tip tool accessibility©International Research Institute for Nuclear DecommissioningNo.436

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(4) Element test plan
[Selection of items to be tested]•
The items to be tested in the element tests to be conducted in this project were selected, based on the results of the studies on
methods for processing structures and fuel debris, and on the status of implementation of element tests so far.

Tip tools that will be tested during the element tests in this projectStatus of element tests conducted so far
Items to be tested inthis project

Processing method

Implementation of element tests during thisproject

Arm

Machine tools*1

Tools*2

Tools*2

Combination with thearm

Circular cutter

Dual motor-operated
arms

✓

-

✓

-＊3
(Proven track recordof using arms isavailable)

Granular fuel debris

SuctionDual motor-operated
arms

-

✓

-

-

Block fuel debris(Brittle portion)

ChiselDual motor-operated
arms

-

✓

-

-

Block fuel debris(Hard portion)

Core boring(Including core cutting)Single hydraulic
arm

✓

-

✓

〇＊4
(Combination withhydraulic arm)

Structures(Interfering objects)*1: Processing test using machine tools that do not consider specifications such as payload, etc. of the access equipment being studied.
The processing time is likely to extend when processing work is carried out using tip tools mounted on remote controlled accessequipment, which are inferior in terms of rigidity or rotational torque of the blade.
*2: Processing test using tip tools that consider specifications of the access equipment being studied.
*3: Test is not conducted as an arm suitable for the payload is not available. There is a track record of cutting of pipes in the past.
*4: Combination test with the test manufactured hydraulic arm and tip tools that consider specifications of the access equipment being
studied.
The impact of the rigidity and vibration resistance of the arms will be verified.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.437① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

Excer(4) Element test plan
[Conceptual designing of the tip tools for the actual equipment]• The functions required of the tip tools will be identified based on the requirements of each work step, and theconceptual design will be developed.
• From among the functions required of the processing tools, those related to processibility will be verified during
the elemental tests.
Functions required of the tip tools and verification items (1/2)
No.
1
1-1

2
2-1

2-2

Work step

Requirements

Required functions

Items to be verified during theelement tests

Advanced preparations
Verification of workability by ・A series of operations must be verified at the site ・Showing the work environment and robot in the form of ameans of a simulator
by means of the simulator.
3D model.
・Being able to operate the 3D model of the robot just likethe actual robot.
On-site work
Moving from cell → processing The cells must be transferred to the predetermined ・The dimensions and mass equal to or lower than thatlocation
location while avoiding obstacles by remote which enables the robot arm to be guided.
operation.
・ Visual inspection function
・The dimensions and mass must be such that the ・3D scanning function
robot arm can be guided.
・Operation system (Function of assisting the operator)
・The surrounding environment must be visuallyobserved or confirmed by means of 3D scanningwhen the robot arm is being guided.
Environment verification

・The condition of the work environment must be ・ Visual inspection function
confirmed by remote operation.
・3D scanning function━━(Tip tools designed withdimensions and mass equal to or
lower than that which enables therobot arm to be guided.)━Circular cutter
2-3
G r a b b i n g t h e i t e m s t o b e ・ Remote operation must be conducted to position ・Grabbing function
removedthe tip tool and grab the items to be removed.
・Function of following the same pattern for the items to be
grabbed・ Visual inspection function
2-4
P r oces s in g t he i te m s t o be ・Remote operation must be conducted to position ・Processing function
grabbedthe tip tool and process the items to be removed.
・Function of verifying the processing status (Speed of the・The blade must be cooled.
motor, etc.)
・Dispersion of machining dust must be reduced.
・Visual inspection function (Verification of surrounding
environment and processing status)
・Blade cooling function
・Dust reduction function
・Measures to prevent getting jammed in the cutter・Operation assistance (Function of assisting the operator)━
・Whether or not processing ispossible (including cooling of
blade)
・Processing conditions (speed,
torque, pressing force) andprocessing time・Life of blade
・Processing reaction force(required pressing force)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.438① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(4) Element test plan
[Conceptual designing of the tip tools for the actual equipment]
Functions required of the tip tools and verification items (2/2)
No.

Work step

Requirements

Content in red: The functions
required of the processing tools.

Required functions

Items to be verified during theelement tests

Suction2-5
S u ction of gr a nul a r fu e l ・ Remote operation must be conducted to ・Suction function
debrisposition the tip tool and suck the granular ・Function of verifying suction status (Status offuel debris.
pump operation, etc.)
・Visual inspection function (Verification ofsurrounding environment and suction status)
・Operation system (Function of assisting theoperator)
Chisel2-6
Processing the items to be ・Remote operation must be conducted to ・Processing function
grabbedposition the tip tool and process the items to ・Visual inspection function (Verification of
be removed.
surrounding environment and processing status)
・Dispersion of dust must be reduced.
・Dust reduction function (Water supply, etc.)
・Operation system (Function of assisting theoperator)
Core boring (Including core cutting)
2-7

2-8

━

━

Processing the items to be ・Remote operation must be conducted to ・Processing function
・Whether or not processing is
grabbedposition the tip tool and process the items to ・Function of verifying the processing status possible (including cooling of
be removed.
(Speed of the motor, etc.)
blade)
・The blade must be cooled.
・Visual inspection function (Verification of ・Processing conditions (speed,
torque, pressing force) and・Dispersion of machining dust must be surrounding environment and processing status)
reduced.
processing time・Blade cooling function
・Dust reduction function
・Life of blade
・Operation system (Function of assisting the ・Processing reaction force
operator)(required pressing force)
・Work in combination with thearms(Stand-alone tool for core
cutting)
Leaving behind the items to ・Remote operations must be conducted to ・Same as 2-1
b e r e m o v e d / s to r i ng i n transfer items to be removed up to the━container
predetermined location
・Same as 2-1©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.439① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(4) Element test plan
[Simulated bodies for the element tests]• The simulated bodies used in element tests so far were not changed. The followings were selected based on
the properties and availability of material derived from fuel debris.
➢ Interfering objects: SUS304, SUS304 + Alumina 99➢ Fuel debris: SUS304 + Alumina 99
・ SUS304 simulates the material of reactor internal structures.
・ Alumina is selected as material which is highly hard and easily obtainable, from among the ceramicmaterial that is considered to be similar to fuel components.
・ In the case of SUS304 + Alumina 99, since both materials are processed under the same conditions,the shape of the blade will be improvised so that it can work on both the materials.

•[Reference] Vickers hardness of ceramic material
Alumina 99: 15.2GPa, Zirconia: 12.3 GPa
The following simulated bodies will be tested in some of the tests.
➢ Interfering objects: SS400 + Alumina 99➢ Fuel debris: SS400 + Alumina 99, granite
・ SS400 simulates the material of structures inside the pedestal.
・ SS400 will be replaced with SUS304, and the processibility of SUS304 and SS400 will be compared.
・ Granite is selected because its hardness is halfway of the metals (SUS304, SS400) and Alumina 99.
・ Processibility of material that is brittle and less hard will be verified with granite.
Note) Hereinafter SUS304 will be referred to as SUS, SS400 as SS and Alumina 99 as Alumina.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.440① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(4) Element test plan
[Specifications of the blade]• Ceramics (Alumina) need to be processed, but generally ceramics are hard due to which cutting (cutting into the material
with sharp blades) is not possible, hence these will be processed using abrasive grains.
• Diamond, CBN (Cubic Boron Nitride) are abrasive grains that are harder than ceramics and have the following
characteristics.
➢ Diamond: The carbon in diamond reacts easily with steel material under high temperatures, and hence it is notsuitable for processing steel material.
➢ CBN: Has better heat resistance as compared to diamond, doesn't react easily with steel material, hence is widelyused for processing steel material.
• This time, since ceramics and steel material need to be processed, a mixture of diamond and CBN will be used asabrasive grains.
Applicability of abrasive grains to ceramics and steel material (metal)
Ceramics

Steel material(Metal)Diamond

✓

△

CBN

x

✓

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.441

Excer(4) Element test plan
[Acquired data]• Processing tests (Refer to the next page onwards) will be conducted for each tip tool (circular cutter, core
boring, core cutting) to obtain the following data.

Acquired data (1/2)
Items

Details

Applicability to actual equipment, issues andresponse measures

Based on the test results, issues in on-site applicability will be identified and response measures will
be studied.

Processibility

The status of processing such as whether or not processing is possible, presence of chatter marks,etc. will be verified.

Processing time

The processing speed will be calculated from the amount of processing and the processing time.
・Circular cutter: **[mm2/min] will be calculated from the processing area (S) and processing time (t).
Processing speed = S/t

Processing area: S

・Core boring: **[mm/min] will be calculated from the processing depth (D) and processing time (t).
Processing speed=D/t

Processing depth: D©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(4) Element test plan
[Acquired data]
Items

No.442

ExcerpAcquired data (2/2)
Details
The amount of processing that can be performed with 1 blade will be calculated based on the heightof the abrasive grains part before processing , the amount of processing and the abrasion loss.
・ Circular cutter: Area that can be processed (= defined as life of the blades) **[mm2] will becalculated from the height of the abrasive grains part before processing (R), processing area (S),height of the abrasive grain part after processing (r).
Life of the blades = R・S/(R-r)

Processing
area: SHeight of the abrasive grain part
before processing: R
Height of the abrasive grain partafter processing: r

Life of the blades

・Core boring: The depth that can be processed (= defined as life of the blades) **[mm] will becalculated from the height of the abrasive grains part before processing (H), processing depth (D)and the height of the abrasive grain part after processing (h).
Life of the blades = H・D/（H-h）
Height of the abrasive grain
part before processing: H
Height of the abrasive grain
part after processing: h

Processing depth: D
Whether the life of the blades can be determined from the current of the motor for rotating the blade,tool slide stroke, etc. will be verified.
Required specifications of remote controlled
equipment (access equipment)

The reaction force involved in the processing (blade pressing force, blade rotating force) will beobtained for provided it as input for the remote controlled equipment (access equipment).

Workability in combination with the arms (Coreboring)

The status of processing such as whether or not processing is possible in combination with the arm,presence of chatter marks, etc. will be verified.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.443(4) Element test plan[Study of test items and testing methods]
Circular cutter (Only the stand-alone tool)•

The specifications required of the actual equipment will be identified for designing the equipment for the element test.
➢ Aerial cutting while lowering the water level is assumed (However, the equipment will have a waterproof structuresince cooling water will splash on it).
➢ The mass is set at 100kg considering the mass of cables and hoses since the payload of the dual motor-operated
arms is 150kg.
➢ The size that can be cut is set at 150mm based on the dimensions of the structure to be cut.

Specifications required of the circular cutter for thedual motor-operated arms
Required functions

It is assumed that the grating, beam,
and CRD exchanger will be cut.

Specifications, etc.

Dimensions

About W600×D500×H550mm: Determined based on the accessibility of the tool

Mass

Maximum 150kg (Target 100kg): Determined based on the payload of the arm

Processing

Circular cutter: Size that can be cut 150mm (Cutter size About Φ400 to 500mm)

Rotational torque of cutter: The largest motor that can be mounted on the tool will be selected
Cutter rotational speed: The largest motor that can be mounted on the tool will be selected
Cooling of blades

Cooling water supply for cutter

Dust control

Installation of cover for preventing dispersion of machining dust
Supply of machining water to the portion to be cut

Visual inspection of partto be processed

Installation of cameras and lights for monitoring the status of processing©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.444

Excerp(4) Element test plan[Study of test items and testing methods]
Circular cutter (Only the stand-alone tool)••

Conceptual planning of the actual equipment based on the specifications required of the actual equipment
Study of test equipment and test items for verifying the functions related to processing from among the functionsof the actual equipment
Circular cutter

Camera & lights

Direction of rotation
Direction of delivery

Tools
CylinderMotor for rotating the cutter

Cooling water
nozzleCircular cutter

Illustration of actual
equipment

・SUS
・SUS + Alumina・(SS + Alumina)

Motor
Material being processed

Illustration of test
equipment

・ 4 layers SUS (t5mm) and Alumina (t5mm) stacked

Sample image oftesting

Processing time・ Processing test will be conducted with the type of blade, speed, pressing
force as the parameters.
・ Workability, processing time, load torque and life of the blade will be verified.

It is assumed that the grating, beam,
and CRD exchanger will be cut.
Load©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.445(4) Element test plan[Study of test items and testing methods]
Core boring (Stand-alone tool + combination with arm)•

The specifications required of the actual equipment (next page) will be identified for designing the equipment for the element test.
➢ Aerial cutting while lowering the water level is assumed (However, the equipment will have a waterproof structure since coolingwater will splash on it).
➢ The payload of the single hydraulic arm is 1 ton, but the target mass will be set at 500kg.
➢ If the cutter is pressed with the arm, the arm bends, but the bend changes depending on the processing reaction force that
depends on the hardness of the object to be processed.
Since the cutter cannot be sent straight ahead if the bend of the arm changes, the tool will be pressed in with the arm, its
reaction force will be received by outriggers at 4 locations, the cutter will be sent in with the cylinder inside the tool under suchconditions and processing (pressing force: Maximum 2ton) will be carried out.
➢•

Colling water will be supplied to the inner side of the blade, and the machining dust will be pushed up from the outer side of theblade.
Conceptual planning of the actual equipment based on the specifications required of the actual equipment
Motor for rotating
the cutter

Cylinder for sending
in the cutter

Outrigger

Camera & lights
Boring cutter
Illustration of actual equipment©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.446(4) Element test plan[Study of test items and testing methods]

Core boring (Stand-alone tool + combination with arm)
Specifications required of the core boring forsingle hydraulic arm
Required functions

It is assumed that a hard layerof block fuel debris will be cut.

Specifications, etc.

Dimensions

About W650×D900×H750mm: Determined based on the accessibility of the tool

Mass

Maximum 1000kg (Target 500kg): Determined based on the payload of the arm

Processing

Core boring cutter: A cutter of diameter Φ65mm which is similar to the Φ66mm cutter used in pastelement tests, and that of diameter Φ130mm aiming for an increase in throughput by reducing theprocessing frequency will be assumed.

Rotational torque of cutter: The largest motor that can be mounted on the tool will be selected
Cutter rotational speed: The largest motor that can be mounted on the tool will be selected
Cutter pressing force: Maximum 2ton (Pressing force of the arm)

Receiving of the cutter pressing force reaction force: Installation of outrigger
Discharge of cutting swarf: Water will be supplied inside the cutter
Cooling of the blade

Cooling water supply for cutter

Dust control

Prevention of dispersion with the help of cooling water for cutter

Visual inspection

Installation of cameras and lights for monitoring the status of processing©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.447(4) Element test plan[Study of test items and testing methods]
Core boring (Stand-alone tool + combination with arm)•

Study of test equipment and test items for verifying the functions related toprocessing from among the functions of the actual equipment
Pressing force= Arm load
Cylinder
Load

Tools

Motor

Core boring
CylinderOutrigger

・SUS + Alumina・(SS + Alumina)
・(Granite)

Material being processed(t10mm)Illustration showing the tool unit test equipment

Processing time・ Processing test will be conducted with the type of
blade, speed, pressing force as the parameters.
・ Processibility, processing time, load torque and life of
the blade will be verified.

Load

It is assumed that a hardlayer of block fuel debris will
be cut.

Illustration of arm combination test

・ Processibility using the arm will be verified underconditions determined during the unit test.
(The impact of the rigidity and vibration resistanceof the arms will be verified）.
Alumina
Alumina

Sample image of testing©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.448(4) Element test plan[Study of test items and testing methods]
Core cutting (Only stand-alone tool)•

The specifications required of the actual equipment will be identified for designing the equipment for the element test.
➢ Aerial cutting while lowering the water level is assumed (However, the equipment will have a waterproof structuresince cooling water will splash on it).
➢ The target mass will be set at 100kg similar to the circular cutter so that it can be handled by both, the dual motoroperated arms and the single hydraulic arm.
➢ Cutting will be performed while holding the core so as to make it easier to retrieve the core after cutting.

Specifications required of the circular cutter for core cutting
Required functions

Specifications, etc.

Dimensions

About W650×D500×H750mm: Determined based on the accessibility of the tool

Mass

Maximum 150kg (Target 100kg) : Determined based on the payload of the arm

Processing

Circular cutter: Determined based on the core boring size
Rotational torque of cutter: The largest motor that can be mounted on the tool will be selected
Cutter rotational speed: The largest motor that can be mounted on the tool will be selected

Cutter pressing: Maximum 300kg
Receiving of the cutter pressing force reaction force: Installation of core clamp
Cooling of the blade

Cooling water supply for cutter

Dust control

Prevention of dispersion with the help of cooling water for cutter

Visual inspection

Installation of cameras and lights for monitoring the status of processing©International Research Institute for Nuclear DecommissioningNo.449

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(4) Element test plan[Study of test items and testing methods]
Core cutting (Only stand-alone tool)••

Conceptual planning of the actual equipment based on the specifications required of the actual equipment➢ The reactor core will be held with the clamping mechanism, the blade will be sent in with the cylinder inside the tool andprocessing will be performed.
Study of test equipment and test items for verifying the functions related to processing from among the functions of the actual
equipment

Direction of rotation

Cylinder forsending in the
cutterMotor forrotating thecutterDirection of delivery

Circular cutter

Tools
CylinderCore clamp

・SUS + Alumina
Sample image of testingLightsCameraMotor・ Since preparation for halving the round bars (Alumina) of
the size of the outer diameter of the reactor core is not aneasy task, it will be replaced with square shaped blocks of thesize of the outer diameter of the core.

Material being processed

Circular cutter
Illustration of
actual equipment

Illustration of test
equipment

Step 1: For setting theprocessing conditions

Load

Core

Processing time・ Processing test will be conducted with the type of
blade, speed, pressing force as the parameters.
・ Processibility, processing time, load torque and lifeof the blade will be verified.

Motor

Circular cutter

Image illustrating theactual equipment test

Core is clamped(Can beretrieved)
・SUS +
Alumina

Step 2: For simulating theactual equipment

・ Whether or not processing will be possible with the tool will be verified.
(Whether or not the processing reaction force can be endured when thecore is clamped.)・ Performance of the core clamp will be verified.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.450① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(5) Designing and manufacturing of tip tools and test equipment for the element tests[Designing and manufacturing of test equipment]•
Test equipment will be designed and manufactured based on results of conceptual studies on the equipment, and results of studies
on test items and test methods.

Cutter pressing
cylinderMotor for rotating
the cutter
Circular cutter

Workpiece

Cutter coolingwater nozzle

Test equipment (Circular cutter)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.451(5) Designing and manufacturing of tip tools and test equipment for the element tests[Designing and manufacturing of test equipment]
Tool pressing cylinder(Used while replacing the cutter)

Motor for rotating
the cutter

Cutter pressing
cylinderArm iterface

Outrigger

Core boring cutter

Workpiece

Test equipment (Core boring)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.452(5) Designing and manufacturing of tip tools and test equipment for the element tests[Designing and manufacturing of test equipment]Core boring work steps
Work
step

1. Outrigger ground contact

2. Outrigger pressing

3. Core boring(Cutter pressing)

4. Core boring(Processing)

Cutterpressing
cylinderIllustration ofwork steps

Outrigger

Details

Camera & lights
Core boring cutter・ Positioning the arm.
⇒ The arm is fixed after it ispositioned.
Only withstands the outriggerpressing force and cutter pressing
force.
・ Extending the outriggers (4 units) toconnect to the ground.

・Further pressurizing the outriggers.
⇒ The outriggers extend further, thetool is lifted up with only the extended
portion and the arm bends upwards.

・Closing the valve of the outrigger
cylinder.

・ Pressing the cutter with the cutterpressing cylinder present inside thetool while rotating the cutter (Cutterpressing foce < outrigger pressing
force).

・Processing with the cutter⇒ The load on the outrigger reduces.
⇒ Outrigger pressing force becomesthe arm pressing force.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.453① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(5) Designing and manufacturing of tip tools and test equipment for the element tests[Designing and manufacturing of test equipment]• The equipment is fixed by clamping the reactor core in the radial direction with 3 claws, the reaction force resulting frompressing of the circular cutter and the force that rotates the equipment resulting from rotation of the circular cutter are
received by the reactor core clamp.
Motor for rotating the cutter
Floating mechanism

Cutter pressing
cylinderCircular cutter

Reactor core clamp

Reactor core

Cutter position guide

Cutter coolingwater nozzle

Test equipment (Core cutting)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.454(5) Designing and manufacturing of tip tools and test equipment for the element tests[Designing and manufacturing of test equipment]Core cutting
Work
step

1. Suspending the equipment

2. Inserting the clamp into thereactor core

Work steps (1/2)
3. Fixing and releasing the floating
mechanism

4. Clamping the reactor core

Guided by the arm in theactual equipment

Floatingmechanism

Illustration ofwork steps

Reactorcore clamp

Floating mechanism
is fixed

Floating mechanism
is released

Cutter position
guide
Reactorcore

Not controlledfrom here on
Cutter position guide

There is no frame in actual equipment

・ Suspending the equipment while
the floating mechanism is fixed.
Details(Performed by the arm in the actual
equipment)

・ Installing on the frame and inserting
the tip of the clamping mechanism into
the reactor core.
(Performed by the arm in the actual
equipment)

・ Releasing the floating mechanism.
・ Lowering the equipment along thereactor core.

・ Clamping the reactor core.

©International Research Institute for Nuclear Decommissioning

Excer

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.455① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(5) Designing and manufacturing of tip tools and test equipment for the element tests[Designing and manufacturing of test equipment]Core cutting
Work
step

5. Fixing the floating
mechanism, and stowing thecutter position guideWork steps (2/2)

6. Core cutting

7. Core cutting completion

8. Core collection

Cutter pressing cylinder

Illustrationofwork steps

Circular cutter

Details

・ Moving the floating mechanismin the fixing direction (to preventthe cutter from getting stuck after
cutting is completed).

・ The size of the cutter pressing
cylinder is reduced and the core iscut.

・ Moving the circular cutter to its
original position after completingcore cutting.

・ Raising the equipment with thehelp of the floating mechanism.

⇒ The equipment follows thereactor core.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.456① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Specifications of the test equipment and acquired data]• Processing tests will be conducted for verifying the processing speed and abrasion loss of core
boring and circular cutter (including core cutting) in order to verify the processibility of the fueldebris and interfering objects.
Specifications of the test equipment
Rotation of blades

Circular cutter(Removal ofinterfering objects)

Core boring

Circular cutter(Core cutting)

・
・
・
・
・

Electric motor
Output: 2.4[kW]Rated torque: 7.64[N･m]Rated rotational speed: 3,000[rpm]Reduction ratio: 2/3, 1/2, 1/4

・
・
・
・
・

Electric motor
Output: 5[kW]Rated torque: 31.8[N･m]Rated rotational speed: 1,500[rpm]Reduction ratio: 1/5, 1/8, 1/16

・
・
・
・
・

Electric motor
Output: 4.5[kW]Rated torque: 14.3[N･m]Rated rotational speed: 3,000[rpm]Reduction ratio: 2/3, 1/2, 1/4

Pressing of blades

BladesWorkpiece・ Hydraulic cylinder
・ Maximum 150[kg]・ Φ 457 × t3.8

・ SUS
・ SUS + Alumina・ (SS + Alumina)

・ Hydraulic cylinder
・ Maximum 2 [ton]・ Φ 130 × Φ118
・ Φ 65 × Φ53.4

・ SUS + Alumina・ (SS + Alumina)・ (Granite)

・ Hydraulic cylinder
・ Maximum 300[kg]・ Φ203 × t3

・ SUS + Alumina©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.457① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Specifications of the test equipment and acquired data]
Common••Test parameters➢ Blade pressing force➢ Rotational speed of the blade
Measured data
➢ Processing speed➢ Life of the blade (calculated based on the abrasion loss)➢ Load torque (calculated based on the motor current)[Test preparation]
Common•The relation between the pressure supplied to the hydraulic cylinder of the test equipment and theblade pressing force is measured.
⇒ The pressing force is controlled by the supplied force.
• The maximum pressing force by which the blade rotates (can process) in the case of eachreduction ratio is measured.
• 3 to 5 cases of pressing forces to be tested (Example: 100%, 75%, 50% and 25% of the maximum
pressing force) are determined from the maximum pressing force.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.458① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Test contents]

List of tests contents (1/2)
Test Item

Circular cutter(Removal ofinterfering objects)

Test contents

Workpiece(1) Processing speed verification test

The processing speed, life of the blade, and load torque are verified withblade pressing force and rotational speed as the parameters.

・・SUS + Alumina
SS + Alumina (some conditions)(2) Test on processing a larger workpiece

The processibility is verified by selecting good conditions based on thetest results in (1), and increasing the blade contact area.

・

SUS + Alumina(3) SUS stand-alone processing test

The processibility of SUS alone is verified by selecting good conditions
based on the test results in (1).

・

SUS

(1) Processing speed verification test

The processing speed, life of the blade, and load torque are verified withblade pressing force and rotational speed as the parameters.

・・・SUS + Alumina
SS + Alumina (some conditions)
Granite (some conditions)(2) Swarf dischargeability verification test

The processibility of the plank is verified (If the processing goes deeper,
dischargeability of swarf worsens and is likely to have an impact onprocessing) by selecting good conditions based on the test results in (1).

・

SUS + Alumina

The processibility if the processing groove is covered is verified (if theprocessing groove is covered, the blade is likely to run towards thepreceding processing groove), by selecting good conditions based on thetest results in (1).

・

SUS + Alumina(3) Test on making a hole for inserting thecircular cutter for core cutting
Core boring

・⑷ 30°incline processing test

The processibility when the part to be processed is inclined 30° is verified(The blade is likely to slide along the incline and have an impact onprocessing) by selecting good conditions based on the test results in (1).

SUS
(Since a plank is required for
simulating the 30°inclined Alumina
workpiece, which is difficult to obtain,
the test is conducted using SUS.)(5) Arm combination test

The processibility of above mentioned (1), (3) and (4) by means of thearm is verified by selecting good conditions based on the test results in (1).

・

SUS + Alumina©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.459① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Test contents]

List of tests contents (2/2)
Test Item

Circular cutter(Core cutting)

Test contents

Workpiece(1) Processing speed verification
test

The processing speed, life of the blade, and load
torque are verified with blade pressing force androtational speed as the parameters.

・ SUS + Alumina
・ SS + Alumina (someconditions)(2) Test for verifying whether
processing is possible using thetool

The processibility when the core is clamped with thetool is verified by selecting good conditions based on
the test results in (1).

・ SUS + Alumina©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.460① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)① Processing speed verification test
• The workpiece shown in the drawing below is processed, and the processing speed, life of the blade (calculated basedon the abrasion loss) and load torque (calculated based on the motor current) are calculated.
• In order to understand the trend, the pressing force and rotational speed over a broad set of 3 - 4 points are consideredand verified.
• Processing is not possible with the arranged motor (2.4kW) and spur gear reduction (1/4) due to lack of torque.
⇒ In the actual equipment, since 1/7 decelerator can be installed within the permissible dimensions, the test is
conducted simulating the torque of 2.4kW motor + 1/7 decelerator by combining the core cutting motor (4.5kW) and the spur
gear reduction (1/4).

Alumina

Alumina

Φ457 x t3.8
Abrasive grainheight 7mm

Circular cutter (Removal of interfering objects)
processing speed verification test

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]No.461① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)① Processing speed verification test•

Processing was possible without any issues and without any chatter marks.
⇒ However, in the future, processing capability using the arms needs to be verified.
• According to the results obtained, the processing speed and life of the blades exceeded the results of past processing
tests.
• The life of the blades can be determined from the drop in the cutter rotating motor load (drop in current).
• It was verified that the data can be reproduced under typical numerical conditions.
Processing speed (Upper level: [mm/min], Lower level: [mm2/min])Rotational
speed
[rpm]
300
425
575
800

•

Pressing force [kN]
0.2
5
14.3
286
15.2
303
20.8
417
27.8
556

0.5
23.8
476
28.6
571
36.2
725
45.5
909

0.6

Rotatio
nal
speed
[rpm]

#1

300

#1

425

37.6
752
#2

Load torque [N･m]Life of the blades (Upper level: [mm], Lower level: [mm2])

575
800

Pressing force [kN]
0.25

0.5

6360
1270005830
116000
4660
93300
3500
70000

7000
1400006360
1270006360
1270004660
93300

Past processing test results➢ Processing speed: 750 [mm2/min], Life of the blades: 1,500 [mm2]➢ Processing speed: 80 [mm2/min], Life of the blades: 19,000 [mm2]Rotatio
nal
speed
[rpm]

0.6

Pressing force [kN]
0.25

0.5

0.6

#1

300

35.4

58.9

#1

#1

425

28.7

47.5

#1

7000
140000

575

24.5

47.5

#2

800

26.1

44.4

56.8
#2

#1: Unable to be processed due to large load torque.
#2: Data unable to be acquired as alumina cracks.
: Good conditions with maximum
processing speed and maximum life of
blades©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests

No.462[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)① Processing speed verification test••

Load torque [N・m]Life of the blades [mm2]Processing speed [mm2/min]Higher the pressing force and rotational speed, faster was the processing speed.
Higher the pressing force, longer was the life of the blades.
⇒ If the pressing force is low, it is presumed that processing does not progress at all and the blade only gets worn out.
• Higher the rotational speed, shorter was the life of the blades.
• Higher the pressing force, larger was the load torque.
• In spite of the variations, even if the rotational speed changed, the load torque remained almost constant.
⇒ The processing load must have been determined by the pressing force, and must not have had any correlation withthe rotational speed. It is believed that the load torque is determined by the contact resistance (this is determined by thepressing force) between the blade and the work piece, and the rotational speed is irrelevant.

Rotational speed [rpm]Pressing force:
0.25[kN]

Pressing force:
0.5[kN]

Processing speed

Rotational speed [rpm]Pressing force:
0.6[kN]

Pressing force:
0.25[kN]

Pressing force:
0.5[kN]

Pressing force:
0.6[kN]Life of the blades

Rotational speed [rpm]Pressing force:
0.25[kN]

Pressing force:
0.5[kN]

Pressing force:
0.6[kN]

Load torque©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.463(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)① Processing speed verification test
• When processing was repeated, the processing speed dropped gradually.
⇒ It was verified that the processing speed is restored by means of dressing#1.
Dressing requires a few seconds.
In the actual equipment, the grindstone for dressing needs to be mounted on the tip tool.

Speed at which cutter is sent in[mm/sec]#1: The action of revealing fresh abrasive grains by scraping off just the layer of bonding material from the surface of thegrindstone with a soft grindstone when there is clogging on the grindstone.

1st round

2nd round

3rd round

Pressing thecircular cutter on
the grindstone
while rotating thecutterStroke at which cutter is sent in [mm]Decline in processing speed due to an increase in the number of processing rounds.

Dressing being conducted©International Research Institute for Nuclear DecommissioningNo.464

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)① Processing speed verification test•
SUS + Alumina was replaced with SS + Alumina, and the processing capability of SUS and SS was compared (implemented
under some of the conditions).
•
Processing was possible without any issues and without any chatter marks.
•
The processing speed was slightly faster in the case of SS, but the life of the blades was shorter and the load torque was larger.
⇒ Generally SS has better processing capability than SUS.
In the case of core boring mentioned later, the processing speed is faster, the life of the blades is longer and the load torque issmaller, in the case of SS.
In the case of processing using abrasive grains, since the grains, the specifications of the bond that hardens the abrasive
grains, the material of the workpiece, processing conditions, etc. are deeply intertwined, according to the blade manufacturer, theprocessing speed and life of the blades will not necessarily show the same tendency.
Processing speed [mm2/min] (Upper level: SUS,
Lower level: SS)
Rotational
speed
[rpm]

0.25

575

━

800

Pressing force [kN]

556
645

0.5

0.6
725
730
909
926

752
#1
#2

Life of the blades [mm2] (Upper level SUS, Lower level：SS)
Rotational
speed
[rpm]

0.25

0.5

575

━

800

70000
66600

127000140,000 #1
63600
93300
#2
60800

Pressing force [kN]
0.6

Load torque [N･m] (Upper level SUS, Lower level: SS)
Rotational
speed
[rpm]

0.25

575

━

800

Pressing force [kN]

26.1
28.0

0.5

0.6
47.5
58.2
44.4
52.0

56.8
#1
#2

#1: Unable to be processed due to large load torque. #2: Data unable to be acquired as alumina cracks.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.465(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)② Test on processing a larger workpiece• The processing capability was verified by selecting good conditions based on the test results in①, and increasing the blade contact area by processing a wider (20 ⇒ 80) workpiece.

Alumina (t10)Alumina (t10)Alumina (t10)Alumina (t10)Φ457 x t3.8
Abrasive grainheight 7mm

Test on processing a larger workpiece with a circular cutter(Removal of interfering objects)©International Research Institute for Nuclear DecommissioningNo.466

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)② Test on processing a larger workpiece• The processing capability was verified by selecting good conditions based on the test results in ①, and increasing theblade contact area by processing a wider (20 ⇒ 80) workpiece.
• Processing was possible without any issues and without any chatter marks.
• However, a thickness of 50 mm was unable to be processed.
⇒ Dressing is required halfway through.
• The processing speed and life of the blades were not much different than the 20 mm workpiece.
• The load torque increased due to the increase in blade contact area.

Processing speed [mm2/min] (Upper level: width 20,
Lower level: width 80)
Rotational
speed
[rpm]

575

800

Rotational
speed
[rpm]

Pressing force [kN]
0.25
417
371
556
714

0.5

0.6
725

#1

752
#1

909
845

#2

Life of the blades [mm2] (Upper level: width 20,
Lower level: width 80)

575
800

Pressing force [kN]
0.25

0.5

0.6

93300
87700
70000
78000

127000140,000 #1
#1
93300
#2
100000

Load torque [N･m] (Upper level: width 20,
Lower level: width 80)
Rotational
speed
[rpm]

575
800

Pressing force [kN]
0.25
24.5
41.1
26.1
38.5

0.5

0.6

47.5
#1

56.8
#1

44.4
57.0

#2

#1: Unable to be processed due to large load torque. #2: Data unable to be acquired as alumina cracks.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.467(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)③ Stand-alone SUS processing test
• The processing capability of stand-alone SUS was verified by processing the workpiece shown in
the following figure under processing conditions described in ②.

Φ457 x t3.8
Abrasive grainheight 7mm

Stand-alone SUS processing test with circular cutter(Removal of interfering objects)©International Research Institute for Nuclear DecommissioningNo.468

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (Removal of interfering objects)③ Stand-alone SUS processing test
• The processing capability of stand-alone SUS was verified by processing a SUS workpiece of width 20 xheight 50 under processing conditions described in ②.
• Processing was possible without any issues and without any chatter marks.
• A tendency to be easier to process as compared to SUS + Alumina was not seen.
• Stand-alone SUS showed almost the same tendencies as SUS + Alumina.
Processing speed [mm2/min](Upper level: SUS + Alumina, Lower level: SUS)

Rotational
speed
[rpm]

575
800

Pressing force [kN]
0.25
417
286
556
614

0.5

0.6
725

#1
909
1920

Life of the blades [mm2](Upper level: SUS + Alumina, Lower level: SUS)

Load torque [N･m](Upper level: SUS + Alumina, Lower level: SUS)

Rotational
speed
[rpm]

Rotational
speed
[rpm]

752
#1
#2

#1: Unable to be processed due to large load torque.
#2: Data unable to be acquired as alumina cracks.

575
800

Pressing force [kN]
0.25

0.5

0.6

93300
53800
70000
60800

127000140,000 #1
#1
93300
#2
82300

575
800

Pressing force [kN]
0.25
24.5
45.4
26.1
36.1

0.5

0.6
47.5

#1

56.8
#1

44.4
53.7

#2

The throughput is evaluated using this data that is
likely to anticipate an improvement in throughput.

•

Based on the test results ① to ③, SUS + Alumina, SS + Alumina, and stand-alone SUS can all be processed, theprocessing speed and life of the blades is the best in all three cases. The test results of SUS + Alumina when thepressing force is 0.5kN and the rotational speed is 800 rpm is used for throughput evaluation.
⇒ An average thickness of 10mm is assumed, processing speed is considered to be 91mm/min and the life of the blade
is considered to be 9,330mm.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.469(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring① Processing speed verification test
• The butt-welded portion of 10mm thick SUS and Alumina was processed, and the processing speed, life of the blades(calculated based on the abrasion loss) and load torque (calculated based on the motor current) were calculated.

Φ65

Φ130

Core boring

Processing speed verification test
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.470(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring① Processing speed verification test
• The butt-welded portion of 10mm thick SUS and Alumina was processed, and the processing speed, life of theblades (calculated based on the abrasion loss) and load torque (calculated based on the motor current) were
calculated.
• In order to understand the trend, the pressing force and rotational speed over a broad set of 3 - 4 points wereconsidered and verified.
• Processing was possible in spite of the chatter marks (The higher the rotational speed, larger were the chattermarks once again in the case of Φ130).
• In particular, chatter marks were large until the blade latched on during the initial stage of processing.
⇒ It is believed that increasing the contact pressure by using a blade with a tapered edge would be effective.
• The resulting processing speed was lower than the past processing test results (2.86mm/minin the case of
Φ66）.
⇒ This is believed to be due to the difference in blades (as blades identical to those used in the previous tests
were unable to be obtained, the test was conducted using different blades) or due to the difference inequipment.
• The life of the blades can be determined from the drop in the cutter rotating motor load (drop in current).
• It was verified that the data can be reproduced under typical numerical conditions.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.471① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring① Processing speed verification test (Φ65)•
The test was conducted using blades with 3 types of hardness.
•
The blades with “medium” and “high” hardness were intended for long life and hence the test was conducted using high pressing force.
•
The processing test was conducted with blades that were 7mm high.
•The life of the blades was evaluated using blades that were 18mm high #1. The issues in processing with blades that were 18mm highare verified in “② Swarf dischargeability verification test”.
#1: Evaluated value from the results of tests conducted using the core bit of the 7mm high blades (the processable depth of every 1mm of the blade
calculated from the abrasive loss of the blade and the processing depth, times 18.)

6

10

63

0.27

0.53

0.60

94

0.24

0.54

0.90

125
188
250
300

Was not conducted due to the numberof tests.

0.19

0.79

1.19

Was not conducted due to the numberof tests.

0.31

1.14

#1

15

63

#2: Unable to be processed due to large
load torque.

94
125
188
250
300

Pressing force [kN]
3

6

10

15

0.87

1.28

Pressing force [kN]
3

6

10

63

23.2

12.1

7.38

0.99

94

30.1

14.2

9.18

1.20

125

1.44

#2

188

1.53
1.09

#2

250

#2

#2

300

0.44
0.17

Rotational
speed
[rpm]

0.63

Life of the blades [mm](Blade hardness: Medium, High)Was not conducted due to the numberof tests.

65.9

33.7

16.6

Was not conducted due to thenumber of tests.

120

45.0

#2

15

Rotational
speed
[rpm]

63
94
125
188
250
300

Pressing force [kN]
3
Unable to be processed as the pressing
force was too low.

3

Rotational
speed
[rpm]

Life of the blades [mm](Blade hardness: Low)

Unable to be processed as the blade
was absent.

Pressing force [kN]

Unable to be processed as the blade
was absent.

Rotational
speed
[rpm]

Processing speed [mm/min](Blade hardness: Medium, High)

Unable to be processed as the pressing
force was too low.

Processing speed [mm/min](Blade hardness: Low)

6

10

15

113
396

80.6

77.8
66.4

101

84.8

55.3

#2

50.2
99.0

#2

#2

#2

The throughput was evaluated using this data that is likely to anticipate an improvement in throughput.
・ Conditions under which the processing speed is the fastest using blades having a life of 50mm or more, considering that aprocessing depth of 50mm or more is required for cutting the core.
・ Conditions under which the processing speed is the fastest using blades having a life of about 100mm when the processing depth isconfigured to 100mm which is double.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.472(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring

Pressing force:
10[kN]
Pressing force:
6[kN]

Processing speed [mm/min]

Processing speed [mm/min]① Processing speed verification test (Φ65)• Higher the pressing force, faster was the processing speed. However, the life of the blades was shorter (Refer to thenext page).
• Lower the hardness of the blades, faster was the processing speed. However, the life of the blades was shorter (Referto the next page).
• Higher the rotational speed, faster was the processing speed.
• Higher the rotational speed, longer was the life of the blades when the blade hardness was “low”, and shorter was thelife of the blades when the blade hardness was “medium” and “high” (Refer to the next page).

Pressing force:
15[kN]
Blade hardness:
High

Pressing force:
10[kN]
Blade hardness:
MediumPressing force:
6[kN]
Blade hardness:
MediumPressing force:
10[kN]
Blade hardness:
High

Pressing force:
3[kN]
Rotational speed [rpm]Rotational speed [rpm]Processing speed [mm/min](Blade hardness: Low)

Processing speed [mm/min](Blade hardness: Medium, High)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.473(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring

Life of the blades [mm]Life of the blades [mm]

① Processing speed verification test (Φ65)• Higher the pressing force, faster was the processing speed (Refer to the previous page). However, the life of
the blades was shorter.
• Lower the hardness of the blades, faster was the processing speed (Refer to the previous page). However,the life of the blades was shorter.
• Higher the rotational speed, faster was the processing speed (Refer to the previous page).
• Higher the rotational speed, longer was the life of the blades when the blade hardness was “low”, and shorter
was the life of the blades when the blade hardness was “medium” and “high”.

Pressing force: 3[kN]
Pressing force: 6[kN]
Pressing force: 10[kN]

Pressing force: 6[kN]
Blade hardness: Medium

Pressing force: 10[kN]
Blade hardness: High

Pressing force: 10[kN]
Blade hardness:
MediumPressing force: 15[kN]
Blade hardness: High

Rotational speed [rpm]Rotational speed [rpm]Life of the blades [mm](Blade hardness: Low)

Life of the blades [mm](Blade hardness: Medium, High)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.474(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring

Pressing force [kN]
3

6

10

15

Rotational
speed
[rpm]

139

162

220

63

94

114

160

234

94

125
188

Was not conducted due to thenumber of tests.

119

166

227

250
300

Was not conducted due to thenumber of tests.

107

161

#1

Unable to be processed as theblade was absent.

63

125
188
250
300

Pressing force: 10[kN]
Pressing force: 6[kN]
Pressing force: 3[kN]

Pressing force [kN]
3

6

10

15

Rotational speed [rpm]195#1: Unable to be processed due to large load torque.

144

206

353

335
176

178

232

#1

261
286

#1

#1

#1

Load torque [N・m]Rotational
speed
[rpm]

Load torque [N･m](Blade hardness: Medium, High)

Unable to be processed as thepressing force was too low.

Load torque [N･m](Blade hardness: Low)

Load torque [N・m]① Processing speed verification test (Φ65)• Higher the pressing force, larger was the load torque.
• Even if the rotational speed changed, the load torqueremained almost constant.

Load torque [N･m](Blade hardness: Low)
Pressing force: 15[kN]
Blade hardness: High

Pressing force: 10[kN]
Blade hardness: High

Pressing force: 10[kN]
Blade hardness: Medium
Pressing force: 6[kN]
Blade hardness: Medium

Rotational speed [rpm]Load torque [N･m](Blade hardness: Medium, High)©International Research Institute for Nuclear DecommissioningNo.475

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring① Processing speed verification test (Φ30)• Test was conducted with blade hardness of “Φ65 (low)”.
• The processing test was conducted with blades that were 7mm high.
• The life of the blades was evaluated using blades that were 18mm high#1.
#1: Evaluated value from the results of tests conducted using the core bit of the 7mm high blades (the processable depth of
every 1mm of the blade calculated from the abrasive loss of the blade and the processing depth, times 18)

Processing speed [mm/min]Rotational
speed
[rpm]

Rotational
speed
[rpm]

Pressing force [kN]
3

6

Load torque [N･m]Life of the blades [mm]10Rotational
speed
[rpm]

Pressing force [kN]
3

6

10

Pressing force [kN]
3

6

10

31

0.07

0.33

0.47

31

59.4

17.5

13.9

31

199

403

467

94

0.23

0.42

1.00

94

59.9

36.0

25.7

94

242

336

559

150

0.13

0.39

#2

150

66.8

67.5

#2

150

172

285

#2

188

0.13

0.50

#2

188

46.8

90.0

#2

188

177

280

#2

0.79

#2

250

71.1

#2

250

299

#2

250

#3

#3

#3

#2: Unable to be processed due to large load torque. #3: Unable to be processed due to large chatter marks.
The throughput was evaluated using this data that is likely to anticipate an improvement in throughput.
・ Conditions under which the processing speed is the fastest using blades having a life of 50mm or more, consideringthat a processing depth of 50mm or more is required for cutting the core.
・ Conditions under which the processing speed is the fastest using blades having a life of about 100mm when theprocessing depth is configured to 100mm which is double.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.476(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring

Rotational speed [rpm]Pressing force:3[kN]

Pressing force:
6[kN]

Processing
speed

Pressing force:
10[kN]

Load torque [N・n]Life of the blades [mm]Processing speed [mm/min]① Processing speed verification test (Φ130)• Higher the pressing force and rotational speed, faster was the processing speed.
• Lower the pressing force, longer was the life of the blades.
• Higher the rotational speed, longer was the life of the blades, but it peaked.
⇒ Higher the rotational speed, faster was the processing speed. Hence it is important to assess the rotational speed
at which the life of the blades is longer.
• Higher the pressing force, larger was the load torque.
• There was no correlation between rotational speed and load torque.

Rotational speed [rpm]Pressing force:3[kN]

Pressing force:
6[kN]Life of the blades

Rotational speed [rpm]Pressing force:
10[kN]

Pressing force:3[kN]

Pressing force:
6[kN]

Pressing force:
10[kN]

Load torque©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.477(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring① Processing speed verification test (Material change, Φ65, Φ130)•
SUS + Alumina was replaced with SS + Alumina, and the processing capability of SUS and SS was compared (implemented
under some of the conditions).
•
Processing was possible in spite of the chatter marks (The higher the rotational speed, larger were the chatter marks once again
in the case of Φ130).
⇒ Tendency identical to SUS.
•In the case of SS, the processing speed was faster, the life of the blades was longer and the load torque was smaller.
⇒ SS has better processing capability than SUS.
Processing speed [mm/min]： Φ65(Upper level: SUS, Lower level: SS)
Rotational
speed
[rpm]
125
250

Pressing force [kN]
10

15
1.20
2.22

━
1.53
2.91

Life of the blades [mm]： Φ65(Upper level: SUS, Lower level: SS)
Rotational
speed
[rpm]
125
250

━

Pressing force [kN]
10

15
66.4
78.3

━

50.2
56.3

━

Load torque [N･m]： Φ65(Upper level: SUS, Lower level: SS)
Rotational
speed
[rpm]
125

250

Pressing force [kN]
10

15
335
309

━
261
219

━

Processing speed [mm/min]： Φ130
(Upper level: SUS, Lower level: SS)

Life of the blades [mm]： Φ130
(Upper level: SUS, Lower level: SS)

Load torque [N･m]： Φ130
(Upper level: SUS, Lower level: SS)

Rotational
speed
[rpm]

Rotational
speed
[rpm]

Rotational
speed
[rpm]

250

Pressing force [kN]
6
0.79
0.88

250

Pressing force [kN]
6
71.1
138

250

Pressing force [kN]
6
299
270
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.478(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring① Processing speed verification test (Material change, Φ65, Φ130)•
SUS + Alumina was replaced with granite, and the processability of material that is brittle and less hard was verified(implemented under some of the conditions).
•
Processing was possible without any issues and without any chatter marks.
•
During the processing conducted this time with 10mm thickness, the blades did not get worn out and hence the life of the blades
was unable to be obtained.
Processing speed [mm/min]： Φ65(Upper level: SUS + Alumina, Lower level: Granite)
Rotational
speed
[rpm]
125
250

Rotational
speed
[rpm]

Pressing force [kN]
10

15

1.20
17.9

━
1.53
25.0

250

6
0.79
10.4

10

15
66.4
Unable to beobtained

━

250

50.2
Unable to beobtained

250

Load torque [N･m]： Φ65(Upper level: SUS + Alumina, Lower level: Granite)

Rotational
speed
[rpm]
125
250

━

Life of the blades [mm]： Φ130
(Upper level: SUS + Alumina, Lower level: Granite)

Rotational
speed
[rpm]

Pressing force [kN]

Pressing force [kN]

125━

Processing speed [mm/min]： Φ130
(Upper level: SUS + Alumina, Lower level: Granite)

Rotational
speed
[rpm]

Life of the blades [mm]： Φ65(Upper level: SUS + Alumina, Lower level: Granite)

Pressing force [kN]6
71.1
Unable to be obtained

Pressing force [kN]
10

15
335
260

━
261
184

━

Load torque [N･m]： Φ130
(Upper level: SUS + Alumina, Lower level: Granite)

Rotational
speed
[rpm]

Pressing force [kN]

250

6
299
137

The throughput was evaluated using this data that is likely to anticipate an improvement in throughput.
・ It was evaluated that the blades do not get worn out.
・ Of the 2 conditions, Φ65 was evaluated under conditions with faster rotational speed.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.479(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring② Swarf dischargeability verification test (Pressing force 10kN, rotational speed 250rpm)•
The butt-welded portion of 50mm thick SUS and Alumina was processed to verify processability of thick plates.
(If the processing goes deeper, dischargeability of swarf worsens and is likely to have an impact on processing)•This test was conducted with blades that were 18mm high, and the strength of the 18mm high blades was verified as well.
•This test was conducted with Φ65 and blades with “medium” hardness.
(In the case of Φ130, as there are several blades, and since the pressing force for each blade and the force resulting from cutter
rotation are both small, the test did not need to be conducted.)•
With a pressing force of 10kN and rotational speed of 250rpm, the chatter marks were large and edge of the blades fell off fromthe base.
⇒ It is believed that the chatter marks became larger due to the large vibrations caused by rattling of the attaching portion andbecause the edge of the blades became longer.
In the future, chatter marks need to be reduced by changing the method of installing the blades and by reducing the length of
the blades (The blades used this time were about 200mm long as they were intended for scraping out, but a length of 100mm should
suffice).
Currently there is rattling, as ease of replacement of theblades was considered.
⇒ In the future, the method of installation will bechanged so that there is no rattling.
The current length of approx. 200mm is too long.
⇒ In the future, the length will be shortened toabout 100mm.

Core boring swarf dischargeability verification test (10kN, 250rpm)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.480(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring② Swarf dischargeability verification test (Pressing force 10kN, rotational speed 125rpm)• The butt-welded portion of 50mm thick SUS and Alumina was processed to verify processability of thick plates.
(If the processing goes deeper, dischargeability of swarf worsens and is likely to have an impact on processing)• This test was conducted with blades that were 18mm high, and the strength of the 18mm high blades was verified aswell.
• This test was conducted with Φ65.
(Since in the case of Φ130, there are several blades, and the pressing force for each blade and the force resulting fromcutter rotation are both small).
• In order to reduce the chatter marks, the pressing force of 10kN was kept as is and the rotational speed was changed
from 250rpm to 125rpm.
(Even if the rotational speed is changed, since the load torque does not change, there is no impact on strengthverification.)• The chatter marks reduced and processing was possible with blades that were 18mm high.
• The processing speed at the initial stage of processing and that at the final stage remained the same.
⇒ Even if the depth of processing increases, there is no impact on processing.

50mmCore boring swarf dischargeability verification test (10kN, 250rpm)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.481(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring③ Test on making a hole for inserting the circular cutter for core cutting• The processability when the butt-welded portion of 10mm thick SUS and Alumina is processed and the processing
groove is covered was verified.
(If the processing groove is covered, the blade is likely to run towards the preceding processing groove).
• Although the blade runs somewhat on the side of the processing groove from the 1 st round, processing is possible.
⇒ It is believed that processability will improve further upon implementing measures to reduce chatter marks (changing
the method of installing the blades, and shortening the length of the blades).
Processing groovefrom the 1st round

During the initial stage of processing, the blades chatter and are not stable.
At approx. 2mm, when the blades slip on the side of the processing groovefrom the 1st round, they become stable.
The test was conducted with a 5.8mm thick blade until the processing
groove widened to approx. 9mm.

2nd round

1st round

Test on making a hole for inserting the circular cutter for core cutting (10kN, 250rpm)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.482(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring④ 30°inclined part processing test•
The processability when the part to be processed is inclined 30° was verified.
(The blades are likely to slide along the inclined part thereby having an impact on processing)•
The test was conducted using an SUS workpiece (Since a thick plate is required for the 30°inclined Alumina workpiece, which isdifficult to obtain)•
Processing was possible if the chattering was controlled by reducing rotations (94rpm).
⇒ It is believed that increasing the rotational speed when the blades have entered to a certain extent is effective in terms ofprocessing speed.
•
While starting the processing, since the blade contact area was small and the contact pressure was high, the pressing force
needed to be gradually increased.
➢ Φ65: Pressing force 2.5kN ⇒ 10kN
➢ Φ130: Pressing force 2.5kN ⇒ 4.5kN•
In the case of Φ130, the blades got used up, and processing was unable to be carried out up to the area where the entire blade
makes contact, but it is believed that if the blades are able to reach up to this area, they do not slide along the inclined surface.
Φ65

Φ130

The test is conducted using
the test piece used for Φ65.

The 4 cornered outriger
is inclined at 30° as well.

Core boring 30°inclined part processing test
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.483(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring⑤ Arm combination test (Core boring equipment installed on the robot arm)
• The processability when the arm is used was verified by selecting good conditions based on the test results in ①.
• The following tests were conducted from among the stand-alone tool tests.
➢ Processing speed verification test
➢ Test on making a hole for inserting the circular cutter for core cutting (Was supposed to be conducted, but has
been canceled. The reasons are described later.)➢ 30°inclined part processing test (Was supposed to be conducted, but has been canceled. The reasons aredescribed later.)

Arm combination test conditions and overview of test results
Blade
size

Pressing
force
[kN]

Rotational speed
[rpm]

Φ65

10

250

Test results

Can be processedArmCannot be processed
Φ65

15

125

Can be processed if the workpiece ischanged from SUS + Alumina to SUS.
Cannot be processed

Φ130

6

250

Tool

Can be processed if the rotational
speed is changed to 125rpm

Arm combination test
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.484(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring⑤ Arm combination test (Φ65, pressing force 10kN, rotational speed 250rpm)••

Processing of SUS + Alumina was possible.
However, the blades entered in an inclined manner and the processing groove became inclined as well.
⇒ The reason for this is that due to the difference in cutting resistance of SUS and Alumina, the rotating joint of the arm rotated slightly.
A swing motor was used for the rotating joint, and since the swing motor had an internal leak, it slightly rotated due to external forces.
It would be effective to add brakes in the future.
Since the cutting resistance is larger in•
The processing speed, life of the blades were almost identical to when the stand-alone tool wasthe case of SUS, the rotating joint of
the arm rotates slightly.
used.
Improvement is likely if the rotating shaft of the arm is fixed.
•
The reason why the processing groove became inclined is believed to be the difference incutting resistance of SUS and Alumina. Hence if stand-alone SUS is processed, vertical processing
is possible.
Inclined
processing

Comparison between stand-alone
tool + combination with arm
Processing
speed[mm/min]Life of theblades[mm]

Standalone
tool

1.53

50.2

Combination with
arm

1.46

42.3

Processing groove of SUS + Alumina

Verticalprocessing

Since the cutting resistance is larger
in the case of SUS, the cutter
deviates upwards to the left.

Direction of rotationof the cutter

Processing groove of stand-alone SUS

Alumina

Reasons for inclined processing©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.485（6） Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring⑤ Arm combination test (Φ65, pressing force 15kN, rotational speed 125rpm)•

Processing of SUS + Alumina was not possible. The equipment slowly shook due to which the blades were unable toenter.
⇒ Looking at the processing marks, it appears that the blades have moved in the same direction as when theprocessing groove became inclined (Refer to the previous page). It is believed that the reason would be the same.
Processing may be possible if the rotating shaft of the arm is fixed.
• In this case as well, processing is possible if stand-alone SUS is processed.
Direction of moevementof the blades

Processing groove of SUS + Alumina

Processing groove of stand-alone SUS•

If the cutting resistance does not act uniformly around the entire circumference of the blade, the rotating joint of the arm moves slightly. In the case of the“Test on making a hole for inserting the circular cutter for core cutting” and the “30°inclined part processing test”, since the cutting resistance does not act
uniformly and the arm moves which is dangerous, it was decided to postpone these tests.
⇒ Since results equivalent to when the stand-alone tool is used are obtained in terms of processing speed and life of the blades, and since it is believed basedon the status of vibrations at the time of processing that the rigidity is equivalent to when the stand-alone tool is used, it is believed that processing is possible if
the rotating shaft of the arm is fixed.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.486① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Core boring⑤ Arm combination test (Φ130, pressing force 6kN, rotational speed 250rpm ⇒ 125rpm)•

With a rotational speed of 250rpm, the chatter marks were large and the blades were unable to enter.
⇒ Processing may become possible upon implementing measures to reduce chatter marks (changing the method of
installing the blades, and shortening the length of the blades).
• Processing was possible if the rotational speed was changed to 125rpm.
⇒ The processing marks were not as conspicuous as Φ65 but the blades moved in the same direction.
• The processing speed, life of the blades were equal to or greather than the results obtained when the stand-alone tool
was used.

Direction of moevementof the bladesComparison between stand-alone
tool + combination with arm
Processing
speed[mm/min]Life of theblades[mm]

Standalone
tool

0.40

52.0

Combination with
arm

0.41

62.1

Arm combination test (Φ130)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.487(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)① Processing speed verification test
• The workpiece shown in the drawing below was processed, and the processing speed, life of the blades (calculated
based on the abrasion loss) and load torque (calculated based on the motor current) were calculated, assuming core
cutting is carried out after core boring of Φ65×Φ53.4.
• In order to understand the trend, the pressing force and rotational speed over a broad set of 3 - 4 points wereconsidered and verified.
Φ203 x t3
Abrasive grainheight 6mm

AluminaCircular cutter (core cutting) processing speed verification test

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.488(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)① Processing speed verification test•

Processing was possible without any issues and without any chatter marks.
⇒ However, in the future, processability using the arms needs to be verified.
• According to the results obtained, the processing speed and life of the blades exceeded the results of past processing
tests.
• The life of the blades can be determined from the drop in the cutter rotating motor load (drop in current).
• It was verified that the data can be reproduced under typical numerical conditions.
Processing speed (Upper level: [mm/min],Lower level: [mm2/min])Rotational
speed
[rpm]

•

Life of the blades (Upper level: [mm], Lower level: [mm 2])

Pressing force [kN]
0.5

0.75

Rotational
speed
[rpm]

1

Rotational
speed
[rpm]

Pressing force [kN]

0.5

0.75

Load torque [N･m]1

Pressing force [kN]
0.5

0.75

1

500

1.85
92.6

9.26
463

16.1
807

500

2850
1420002140
107000

1270
63800

500

36.6

50.4

58.4

750

3.18
159

11.6
581

19.2
962

750

3520
1760002720
1360001990
100000

750

32.3

44.0

51.3

1000

3.91
195

10.0
500

#1

1000

3750
1870002500
124000

#1

1000

23.6

31.4

#1

1200

4.20
210

9.62
481

#1

1200

2720
1360002850
142000

#1

1200

21.6

27.8

#1

Past processing test results➢ Processing speed: 750[mm2/min ], Life of the blades: 1,500 [mm2]➢ Processing speed: 80[mm2/min ], Life of the blades: 19,000 [mm2]#1: Unable to be processed due to large load torque.
: Good conditions with maximum
processing speed and a good balance ofprocessing speed and life of blades©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.489(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)① Processing speed verification test
•
•
•
•
•

Load torque [N・m]Life of the blades [mm2]Processing speed [mm2/min]Higher the pressing force and rotational speed, faster was the processing speed.
Lower the pressing force, longer was the life of the blades.
Higher the rotational speed, longer was the life of the blades.
Higher the pressing force, larger was the load torque.
Higher the rotational speed, smaller was the load torque.
⇒ The processing load must have been determined by the pressing force, and must not have had any correlation withthe rotational speed. Even if the rotational speed increased, the processing speed did not increase as much.
When the rotational speed is high, it is believed that the engagement between the abrasive grains and the workpiece
becomes superficial, the processing speed does not increase as much, and the load torque reduces.

Rotational speed [rpm]Pressing
force: 0.5[kN]

Pressing force:
0.75[kN]

Rotational speed [rpm]Pressing
force: 1[kN]

Processing speed

Pressing
force: 0.5[kN]

Pressing force:
0.75[kN]

Rotational speed [rpm]Pressing
force: 1[kN]Life of the blades

Pressing
force: 0.5[kN]

Pressing force:
0.75[kN]

Load torquePressing
force: 1[kN]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests

No.490[Processing test using the tip tools and evaluation of processing test results]

Circular cutter (core cutting)Speed at which cutter is sent in[mm/sec]① Processing speed verification test
• When processing was repeated, the processing speed dropped gradually.
⇒ It was verified that the processing speed is restored by means of dressing#1.
Dressing requires a few seconds.
In the actual equipment, the grindstone for dressing needs to be mounted on the tip tool.
#1: The action of revealing fresh abrasive grains by scraping off just the layer of bonding material from the surface of thegrindstone with a soft grindstone when there is clogging on the grindstone.
.

1st round

2nd round

Stroke at which cutter is sent in [mm]Decline in processing speed due to an increase in the number of processing rounds.

Pressing thecircular cutter on thegrindstone whilerotating the cutter

Dressing being conducted©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.491(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)① Processing speed verification test
• SUS + Alumina was replaced with SS + Alumina, and the processability of SUS and SS was compared (implemented
under some of the conditions).
• Processing was possible without any issues and without any chatter marks.
• The processing speed was faster in the case of SS, but the life of the blades was shorter and the load torque was larger.
(Same tendency as the circular cutter for removing interfering objects)⇒ Generally SS has better processability than SUS.
In the case of core boring mentioned earlier, the processing speed was faster, the life of the blades was longer andthe load torque was smaller, in the case of SS.
In the case of processing using abrasive grains, since the grains, the specifications of the bond that hardens theabrasive grains, the material of the workpiece, processing conditions, etc. are deeply intertwined, according to the blade
manufacturer, the processing speed and life of the blades will not necessarily show the same tendency.

Processing speed [mm2/min](Upper level: SUS, Lower level: SS)
Rotational
speed
[rpm]
750

Pressing force [kN]
0.75

1
581
926

962
1040

Life of the blades [mm2](Upper level: SUS, Lower level: SS)
Rotational
speed
[rpm]
750

Pressing force [kN]0.75

1136000
60000

10000048300

Load torque [N･m](Upper level: SUS, Lower level: SS)
Rotational
speed
[rpm]
750

Pressing force [kN]
0.75
44.0
53.7

1
51.3
62.3

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.492(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)② Test for verifying whether processing is possible using the tool•
The clamping performance and processability when the tool is used was verified by selecting good conditions (pressing force 1kN,
rotational speed 750rpm) based on the test results in ①, and processing the workpiece shown in the figure below.
□25 (Alumina)
・25 x t10 x 2
・25 x t5

Core clamp
Φ53(SUS)
Circular cutter

Clamping the coreCore

Circular cutter

Core

Motor

Test for verifying whether core cutting is possible©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.493(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)② Test for verifying whether processing is possible using the tool•

Processing was possible without any issues and without any chatter marks. ⇒ There was no issue in clamping
performance.
• The processing speed and life of the blades were less than the element test without the clamp.
⇒ In the element test without the clamp, the ratio of SUS and Alumina was fifty-fifty, but in this test, since the ratio of
SUS which is difficult to cut, was higher, the processing speed and life of the blades were lower.
• Core clamping (from completion of positioning on the core to start of cutting) required 1.5 minutes.
⇒ This was included in throughput evaluation.
• There were no issues in the workability of the series of tasks from core clamping to core retrieval.
Comparison of processing speed and life of blades
Processing
speed[mm2/min]Life of theblades[mm2]

Element testwith no clamp

962

100000Tool witha clamp

826

52900

: The throughput was evaluated using this data that is likely toanticipate an improvement in throughput.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.494(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)② Test for verifying whether processing is possible using the tool
Results of the test for verifying whether core cutting is possible (1/2)

№

Items

1

Does the equipment go down along
the reactor core?

Good

Can go down with its own weight.

2

Does the equipment follow thereactor core due to the reactor coreclamp? (Does the incline getcorrected?)Good

The incline can be corrected bylifting up the floating mechanism
after clamping.

3

Is core cutting possible?

Good

Cutting is possible.
There was no issue in gripping
force of the clamp.

Test results©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.495(6) Tip tools element tests[Processing test using the tip tools and evaluation of processing test results]
Circular cutter (core cutting)② Test for verifying whether processing is possible using the tool
Results of the test for verifying whether core cutting is possible (2/2)
№

Items

Test results

Good

Did not get stuck.
There were no issues in the
movement of the circular cutter
back to its initial position.
It was verified that after the cutter
moves back, there is a gap
between the cutter and the cut
portion.

5

Is retrieval of the reactor corepossible?

Good

Can be retrieved.
The reactor core did not fall evenas the equipment was lifted up.

6

Does the reactor core fall when thecore clamp is released?

Good

The reactor core falls when thecore clamp is released.

4

Does the circular cutter get stuckafter completing core cutting?

©International Research Institute for Nuclear DecommissioningNo.496

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Evaluation of processing test results]① Required specifications of remote controlled equipment (access equipment)•
The processing reaction forces (blade pressing, blade rotation) obtained from the test
results were consolidated as requirements of the robot arm.
⇒ The maximum values were identified from the test conditions used for evaluating
throughput.
The horizontal reaction force was calculated from the load torque and the blade size.
•
The structure of the chisel was such that the chisel equipment is suspended with a chain
just like it was done in past tests, and the chisel is pressed with the cylinder inside thechisel equipment. Thus, the vibrations of the chisel can be prevented from getting
transmitted to the arm.
•
The arm length and number of shafts were not included in the study this time since theaccess had to be studied while considering dodging of interfering objects.

Chisel equipment
suspension cylinder
Suspension
mechanism(Mass: 50kg）
Chisel equipment(Mass: 100kg）

Chisel pressing
cylinderChiselPayload and processing reaction force required of the robot arm
Payload[kg]

Pressing
reaction
force
[kN]

Horizontal
reaction
force
[kN]

Rotational
torque[N･m]Circular cutter

150

0.5

0.1

━ #1

Core boring

1000

15#3

4.6

299

Core cutting

150

━ #1

━ #1

━ #1

Chisel

150

━ #1

━ #2

━ #2

#1: Since the reaction force is received inside the tool, the reaction force does not act on
the arm.
#2: Does not get generated while processing with a chisel.
#3: Outrigger pressing force 5kN is applied to the processing reaction force.

(Processing position)(Guiding position)

Chisel equipment guiding method
Pressing
reaction force
Pressing
reaction force

Rotational
torqueHorizontal
reaction force
Horizontal
reaction force(Circular cutter)(Core boring)

Reaction force due to processing©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.497① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)(6) Tip tools element tests[Evaluation of processing test results]② Throughput evaluation• The throughput evaluation carried out as part of the “1F-3 Fuel Debris Retrieval Method Conceptual Study Contract(Part 3)” outsourced to TEPCO in FY2021 was evaluated once again using the throughput evaluation data obtained
this time (including the data obtained by the operating system mentioned later).
• Core boring of the block fuel debris which comprises a lot of time of the throughput was evaluated under multiple
processing conditions.

•
•
•

•

Although the time required for processing using the circular cutter did not change, the throughput was able to be
reduced by reducing the frequency of blade replacement by increasing the time taken for positioning the tool and byextending the life of the blades.
In the case of core boring, the processing speed as well as the life of the blades were lower than the previous
throughput evaluation results, and the throughput increased.
In particular, the life of the blades was configured based on an assumption the previous time and was thus
significantly short. This was the main reason for the increase in throughput this time.
The size of the blades was increased (Φ66mm⇒ Φ130mm) in order to improve throughput, but throughput improved
due to a drop in processing frequency.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.498(6) Tip tools element tests[Evaluation of processing test results]③ Applicability to actual equipment, issues and response measures• In the case of the circular cutter, processability using the robot arm needs to be verified. In the case of core boring, inspite of pending issues such the necessity to add a brake to the robot arm, etc., there are prospects of being able toapply it to the actual equipment.
• Measures in response to the issues that became evident as a result of the processing tests conducted this time werestudied.

Issues and response measures (1/3)№

IssuesResponse measures(1) The object to be cut expands due to the heat generated during processing and the cutter gets stuck.
⇒ Instead of using a rimmed disc-shaped cutter, a segmented cutter with slits all around the circumference, and which has
good heat dissipation properties should be used, and cooling water should be used as well. ……Already used in the processing
test conducted this time.
(2) The object to be cut gets deformed right before cutting is completed, and the cutter gets stuck.
⇒ The plan is to use dual arms, such that one arm holds and the other arm cuts. Whether deformation can be controlled bymeans of the arms should be verified by conducting a processing test using the arms.

・Jamming of the circular cutter
1

Although this didn’t occur during
the test conducted this time, since it
is likely to occur during the actual
work, measures need to be taken.

(3) Retrieving the arms if the cutter gets jammed.
⇒ Even if the circular cutter gets jammed, the arms must be retrieved.
Whether the arms can be retrieved by the following methods should be verified by conducting the test using the arms.
① Leaving only the circular cutter behind and retrieving the arms.
The circular cutter should be installed using a 3-jaw chuck so that when the chuck is released only the circular cutter isleft behind.
② Leaving the cutting tool behind and retrieving the arms.
The cutting tool should be separated using the tool changer and left behind.
Cutting tool

Circular cutter② Separating with the tool changer① Separating by releasing the 3-jaw chuck(Note) The contents listed under “Response measures” are planned to be studied during engineering, etc. in the future.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.499(6) Tip tools element tests[Evaluation of processing test results]③ Applicability to actual equipment, issues and response measures

Issues and response measures (2/3)№

IssuesResponse measures

・Processability of the circular cutter
when the arms meant for the actual
equipment are used
2

There were prospects of being able
to process with the stand-alone tool,
but the processability when the arms
meant for the actual equipment areused needs to be verified.

The impact of the rigidity and vibrations of the arms should be verified by conducting processing tests using the arms meant
for the actual equipment.

A grindstone for dressing should be mounted on the processing tool for carrying out dressing in the vicinity of the area wherecutting is performed withoutGrindstone
retrieving theequipment inside the cell.
transfermechanism
・Dressing of the circular cutter
3

The processing speed gradually
drops due to clogging, etc. of thegrindstone. Dressing is required
halfway through the processing.

Grindstone pressing
mechanism

Grindstone for dressing
Circular cutter

Circular cutter pressing
mechanism
Grindstone transfer
mechanism
Core cutting

Grindstone
for dressing(Note) The contents listed under “Response measures” are planned to be studied during engineering, etc. in the future.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.500(6) Tip tools element tests[Evaluation of processing test results]③ Applicability to actual equipment, issues and response measures

Issues and response measures (3/3)№

Issues・Chatter marks during the initialstage of core boring

4
It takes time for the blades to latch
on due to chatter marks.

Response measures(1) In order to increase the contact pressure during the initial stage of processing, blades should be changed to those withtapered edges.
(2) The rattling of the cutter installation part should be controlled in order to control run-out of the blade edge.
(3) The length of the cutter should be shortened in order to control run-out of the blade edge.

・Core boring blades replacement
frequency
5

The life of the blades is short andthe time required for changing theblades has a major impact on thethroughput.

・ Rotation of the rotating joint of thearm during core boring
6

Whether changing the specifications (size, shape and quantity of abrasive grains) of the abrasive grains would be effective
should be verified.
However, as the processing speed and life of the blades change depending on the composition of the target object, during
actual work, measures should be taken according to the circumstances.

The swing motor used for the rotating joint has an internalleak due to which external forces act on the joint resulting inslight rotation.

Since the cutting resistance is larger in thecase of SUS, the rotating joint of the arm
rotates slightly.
Since the cutting resistanceis larger in the case of SUS,
the cutter deviates upwards
to the left.

Brakes should be added in order to cotrol the rotation.
The rotating joint of the arm slightly
rotates due to the horizontal reaction
force during core boring because ofwhich the blade egde moves.

Direction of rotationof the cutter
Alumina(Note) The contents listed under “Response measures” are planned to be studied during engineering, etc. in the future.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.501(6) Tip tools element tests[Evaluation of processing test results]④ Summary of test results•
In the case of the circular cutter, processability using the robot arm needs to be verified. In the case of core boring, in spite ofpending issues such a the necessity to add a brake to the robot arm, etc., there are prospects of being able to apply it to theactual equipment.
•
Issues were identified and response measures were studied.
•Throughput evaluation data was obtained and the throughput was re-evaluated.
•
The processing reaction forces (blade pressing, blade rotation) obtained from the test results were consolidated as
requirements of the robot arm.

Overview of test results (1/3)
Test item(1) Processing speed
verification test
Circularcutter(Removal ofinterfering
objects)(2) Test on processing alarger workpiece

Overview of test results

Considerations and countermeasures

・ Processing was possible without any issues and without any chattermarks.
・ The processing speed, life of the blades, and load torque were obtainedwith blade pressing force and rotational speed as the parameters.

・ A conceptual diagram illustrating the mounting of agrindstone for dressing on to the tip tool has been created.

・ The processing speed as well as life of the blades exceeded the resultsof past processing tests.
・ When processing was repeated, the processing speed dropped
gradually, but the processing speed was restored upon carrying out
dressing for several seconds.
・ Even if the blade contact area increased, the processing speed(mm2/min) and the life of the blades (mm2) did not change.

・ If the blade, guide and cylinder are not in a straight line,
the pressing cylinder thrust is not equal to the blade
pressing force due to loss caused by momentum. Hencethe actual equipment needs to be designed carefully.

━

・ The load torque increased due to the increase in blade contact area.
(3) Stand-alone SUS
processing test

・ SUS that is difficult to cut can be processed without any issues.

━©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.502(6) Tip tools element tests[Evaluation of processing test results]④ Summary of test results
Overview of test results (2/3)
Test item(1) Processing speed
verification test

Overview of test results

・ Processing was possible in spite of chatter marks.
・ The processing speed, life of the blades, and load torque wereobtained with blade pressing force and rotational speed as theparameters.
・ The processing speed was lower than the results of past processing
tests. However, by increasing the size of the core, equivalent or higher
results were obtained.

・ In the 50mm depth processing test, as a result of the processing
conditions, chatter marks were large and there was blade damage.
(2) Swarf dischargeability
verification test
Core boring(3) Test on making a holefor inserting the circular
cutter for core cutting⑷ 30°inclined partprocessing test

・ The processing speed at the initial stage of processing and that at the
final stage remained the same
(Even if the depth of processing increased, there was no impact onprocessing).

・ Although the blade runs somewhat on the side of the processing
groove from the 1st round when the processing groove is covered,processing is possible.

・ Processing was possible if the chatter marks were controlled by
reducing the rotational speed.
・ Processing was possible if the pressing force was kept low at the startof processing.

Considerations and countermeasures

・ It is believed that increasing the contact pressure by using a blade with atapered edge would be effective to overcome the impact of chatter markspresent during the initial stage of processing.
・ If the blade, guide and cylinder are not in a straight line, the pressing
cylinder thrust is not equal to the blade pressing force due to loss caused bymomentum. Hence the actual equipment needs to be designed carefully.

・ It is believed that the rattling of the blade installation part and increase in
run-out of the blade tip caused by the increased length of the blade edge
were the reasons for the chatter marks.
⇒ In the future, chatter marks need to be reduced by changing the methodof installing the blades and by reducing the length of the blades (The blades
used this time were about 200mm long as they were intended for scraping
out, but a length of 100mm should suffice).

━・ It is believed that keeping the rotational speed low at the initial stage ofprocessing and then increasing the rotational speed when the blades haveentered to a certain extent is effective in terms of processing speed.
・ While starting the processing, since the blade contact area is small andthe contact pressure is high, the pressing force needs to be gradually
increased.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.503(6) Tip tools element tests[Evaluation of processing test results]④ Summary of test results
Overview of test results (3/3)
Test Item

Core boring(5) Arm combination
test

Overview of test results

・ Processing was possible by combining the tool with the arm.
However, the blades entered in an inclined manner and theprocessing groove was inclined as well.
・ The processing speed, life of the blades were almost identical towhen the stand-alone tool was used.

・ Processing was possible without any issues and without any
chatter marks.
・ The processing speed, life of the blades, and load torque wereobtained with blade pressing force and rotational speed as theparameters.
(1) Processing speed
verification test

・ The processing speed as well as life of the blades exceeded theresults of past processing tests.

Considerations and countermeasures

・ It is believed that the blades entered in an inclined manner as therotating joint of the arm rotated slightly due to the difference in cutting
resistance of SUS and Alumina. It would be effective to add brakes in
the future.
・ The reason why the processing groove became inclined is believed tobe the difference in cutting resistance of SUS and Alumina. Hence if
stand-alone SUS is processed, vertical processing is possible.

・ A conceptual diagram illustrating the mounting of a grindstone fordressing on to the tip tool has been created.
・ If the blade, guide and cylinder are not in a straight line, the pressing
cylinder thrust is not equal to the blade pressing force due to loss
caused by momentum. Hence the actual equipment needs to be
designed carefully.

・ When processing was repeated, the processing speed dropped
gradually, but the processing speed was restored upon carrying out
dressing for several seconds.

Circular cutter(Core cutting)(2) Test for verifying
whether processing ispossible using the tool

・ Processing was possible without any issues and without any
chatter marks.
・ There were no issues in the workability of the series of tasks fromcore clamping to core retrieval.

・ In the element test without the clamp, the ratio of SUS and Alumina
was fifty-fifty, but in this test, since the ratio of SUS which is difficult tocut, was higher, the processing speed and life of the blades were lower.

・ The time required for core clamping has been reflected in thethroughput evaluation.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.504✓ Results• Applicability of the tip tools to actual equipment, issues and response measures.
• Data for throughput evaluation, and throughput evaluation.
• Required specifications of remote controlled equipment (access equipment).
✓ Contribution of the results towards the reflection destination• The concreteness of the fuel debris retrieval equipment improved through studies on measuresin response to the issues obtained as a result of processing tests.
• The throughput was refined.
✓ Analysis from the viewpoint of applicability to the site
• The accessibility of the tip tools inside the pedestal was studied, and the dimensions of the tip
tools were determined.
• The properties of fuel debris were unknown, but SUS was selected for simulating reactor
internal structures and Alumina was selected for simulating fuel components, and assuming thatthese were mixed at the site, processing of SUS and Alumina simultaneously was tested.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Tip tools)

No.505✓ Level of achievement compared to the goals
All goals were achieved.
• Processing tests with the processing conditions extensively considered as parameters wereconducted, processability was verified and the data for throughput evaluation was obtained.
• The size of core boring had to be increased but it was effective in reducing the processing time.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.506✓ Objective
The load on the operator will be reduced and work efficiency will be enhanced by means of the operation systemthat supports remote operation.
✓ Project goals• Tests will be conducted with mock-ups simulating the inside of the Unit 3 pedestal using the test
manufactured operation system, to verify the procedures for grabbing/cutting/transferring interfering objects
and collecting the fuel debris in unit cans, and the viability of the series of operations will be verified. Also,data will be created for throughput evaluation by acquiring and consolidating actual results of work
procedures.
• Case studies on the operation system application conditions, assumed issues, etc. will be consolidated as
an input for planning the procedures for disassembly and removal.
✓ Implementation items• Test manufacturing of the operation system, verification of viability of the series of operations by means ofmock-up tests.
• Acquisition of actual data on the work procedures, creation of data for throughput evaluation.
✓ Outcome (FY2022)• Acquisition of actual data on the work procedures, creation of data for throughput evaluation.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.507

An operating system that supports remote operation by the operator⚫

Background of development
The work of removing interfering objects and retrieving fuel debris will be carried out while
avoiding obstacles in a confined space such as that of the PCV. (Figure 1)⇒ A manipulator with a redundant degree of freedom will be effective: As it has 7 ormore joints, and its elbows can be evasively maneuvered while retaining the posture andposition of the arm tip. (Figure 2)⚫

Issues that must be resolved
Remotely operating the manipulator with a redundant degree of freedom while avoiding
obstacles under conditions with limited visibility puts too much load on the operator, andthe manipulator could collide with obstacles.

⚫

Purpose of development
The load on the operator will be reduced and work efficiency will be enhanced by meansof the operation system that supports remote operation (Supports the manipulator in
avoiding obstacles).

⚫

Course of development➢ Study of operation system➢ Development of operation system➢ Verification of effectivenessby means of element tests ⇒Verification of operating time of the manipulator through⚫

Figure 1
Illustration ofinterference removal work in Unit 3

Arm tip

mock-up tests and reflection into the throughput

Expected outcome
Automation of operation of the manipulator to avoid obstacles, enhancement of safety andefficiency of work
(Application to various other work and robots in the future will be aimed for.).

Elbow
Obstacles

Base
Figure 2 Evasive maneuvering of the manipulator
with redundant degree of freedom©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5） Implementation items (Operating system)

No.508An operating system that supports remote operation by the operator⚫ Fuel debris retrieval work flow (Example)
Work plan⓪ Prior verification ofwork(Using the simulator)① Moving inside thepedestal

On-site work

② Grabbing andcutting the items to be
removed

③ Transferring ofitems to be removed
outside the pedestal④ Leaving behind thetransferred items to be
removed / storing incontainer

Pedestal opening

The structures (damaged) just inside theopening will be specified as the primary
items to be removed(As these hinder manipulator work)⓪ The items to be removed will be determined using the simulator, and the viability of manipulator work will be verified.
・ It is assumed that the interfering objects outside the pedestal have been removed.
・A 3D model of the inside of the pedestal has been developed up to a certain extent with a certain accuracy based on theinternal investigation.
・ Viability of the series of removal work will be verified by means of a simulator.
・ The procedures for removing collapsed structures will need to be studied separately.
・ There are two kinds of removal procedures, namely, “Removing sequentially from the front” and “Removing the items fromthe back while avoiding obstacles”. The level of difficulty of the latter is higher.
(Tests that have a higher level of difficulty will be set up.)

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.509An operating system that supports remote operation by the operator⚫ Fuel debris retrieval work flow (Example)
Work plan⓪ Prior verification ofwork(Using the simulator)① Moving inside thepedestal① Moving the hand cutter to the area around the items to be removed (10 to 20 cm in front) while avoiding obstacles
・ 2 manipulators and their bases (access rail) are interlinked and together avoid obstacles and move objects
・ The trajectory plan has been developed during the “Development of techniques for remote operation support inenvironments with low visibility and narrow spaces” in FY2020.

CutterInterference removal equipment[Preparation site]

Interference removal equipment[Preparation site]

On-site work

② Grabbing andcutting the items to be
removedInside the pedestal③ Transferring ofitems to be removed
outside the pedestal

Items to be removed

Hand④ Leaving behind thetransferred items to be
removed / storing incontainer

Items to be removed

Pedestal
opening©International Research Institute for Nuclear Decommissioning

No.510

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)
An operating system that supports remote operation by the operator⚫ Fuel debris retrieval work flow
Work plan⓪ Prior verification ofwork(Using the simulator)① Moving inside thepedestal

On-site work

② Grabbing andcutting the items to be
removed② Grabbing the items to be removed with the hand and cutting the items to be removed with a cutter[Grabbing] The operator slightly moves the hand manually while confirming the camera images, etc.
(Bottom left figure: Movement from A → B)
[Cutting] The operator slightly moves the cutter manually while confirming the camera images, etc.
(Bottom right figure: Movement from C → D)
After cutting, the arm tips (hand and cutter) are moved back to spots A and C respectively.
・ Work space (space) in which the manipulator can move slightly will be secured in advance （⓪）
・ Verification of gripping force, method of determining the cutting location, method of adjusting the cutting
speed, etc. will be studied separately.
A: Movement
end pointin thetrajectory plan

B：Grabbing point

C: Movement end pointin the trajectory plan

③ Transferring ofitems to be removed
outside the pedestal
D：Cutting end
point④ Leaving behind thetransferred items to be
removed / storing incontainer
Illustration of work of grabbing by hand

Illustration of work of cutting with cutter©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.511An operating system that supports remote operation by the operator⚫ Fuel debris retrieval work flow
Work plan⓪ Prior verification ofwork(Using the simulator)① Moving inside thepedestal

On-site work

② Grabbing andcutting the items to be
removed

③ Transferring ofitems to be removed
outside the pedestal③ Grabbing the item to be removed and moving it outside the pedestal while avoiding obstacles[Same procedure as aforementioned ①]
・ The route for avoiding obstacles is automatically generated using the trajectory plan, including the items
to be removed that are grabbed by the hand.
# Measures for preventing the grabbed object from falling will be studied separately
Inside the pedestal

Separate trajectory plans will be made forthe onward route and the return route.
・ Part of the environment changes
・ The robot model changes

Items to be
removed

④ Leaving behind the items to be removed (structures/fuel debris) at the PCV bottom / storing in unitcans・ “Structures to which fuel debris is not adhered” are left behind in the PCV (Bottom left figure)・ The “fuel debris” is placed in the unit can, the unit can trolley travels over the rail and is transferred outside
the PCV (Bottom right figure)The method of determining whether or not fuel debris is adhered needs to be established separately.
Left behind at
the PCVbottom

④ Leaving behind thetransferred items to be
removed / storing incontainer
Unit can©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.512

Overview of the trajectory plan developed until
last year

Information on the robot andenvironment

Trajectory plan algorithm

Robot
Motor for each joint• 3D model of the robot• 3D model of the environment• Camera image

Goal isdetermined• Route computation up to
the destination• Determination of collision
with the robot model andthe environment model →Computation of position
so that both do notinterfere with each other

Servo controller
Target angle ofeach joint is
outputOrder to each joint

Integrated controller

Operator manipulates
the replay speed

Operator©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.513Issues with the trajectory plan

⚫ There is a risk of missing obstacles
The route from the start to the goal is divided into smaller
segments, and the obstacles are determined for each moment in
the divided segments.
⇒ If the number of segments is less (roughly), the obstacles in
between them get missed.
If the number of segments is increased, the computation timeincreases as a trade off.

Obstacles⚫ As the work of high accuracy positioning such as for grabbing,cutting, etc. is switched over to manual operation, the risk ofcollision increases.
When the hand or cutter is slightly moved towards the target object, minor
adjustments in millimeters are made based on the camera images. As
such minute movements are not included in the trajectory plan, theoperation needs to be switched to manual operation.
⇒ As manual operation heavily relies on the skills of the operator, therisk of collision is high particularly in the case of beginners.
As the focus remains completely on the arm tip, the risk of collision by
the elbow, etc. is high.
Image illustrating work of grabbing by hand©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.514Development details
A “Trajectory plan” will be incorporated into the operating system as a measure for resolving issues.
The trajectory plan consists of the following 2 types.
Joint research with Kobe University
Local trajectory plan

Wide range trajectory plan

Start

(Example of 4 segments)

Current location
Position after
0.1 seconds

Goal
Conceptual diagram

Route computation
Determination of collision
Computation time

A series of movements from start to the goal (separate)

Only the position after 0.1 seconds

Computation of position so that both do not interfere with each other by determining collision with the robot model and the environment
model.
Long (Number of segments: 20 to 30 segments of 1 to 2 minutes)

Short (Target: 0.1 seconds or less)Computed in advance and verified by operator using the simulator
Timing of computation- (Not real time)
Main operation method

Foot pedal (Adjustment of speed based on the extent to which thepedal is stepped on)

Real time (Sequential computation as the robot moves)Game pad (Operating with the position of the arm tip and theposture)[Additional Notes]
The margin value (gap between the robot and the environmental model) was set at 40mm in the mock-up test conducted this time.
(The mock-up manufacturing accuracy, laser sensor measurement accuracy and position adjustment tool repetition accuracy total to approx. 20mm. The
margin was set by doubling this number.
However, the accuracy of repetitive positioning by means of crawler movement has not been considered.)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.515

Measures to resolve the issues with the trajectory plan
There is a risk of missing obstacles ⇒ Obstacles will not be missed by means of the “Local trajectory plan”
Information on the robot
and environment• 3D model of the robot• 3D model of theenvironment

Local trajectory plan

Wide range trajectory plan

Rough trajectory
Consists of 2 stages comprising creation of aseries of tasks from start to the goal (roughtrajectory) based on the Wide range trajectoryplan, and then interpolation of the gaps by the
Local trajectory plan.

Robot

Detailed trajectory
Route up to thegoal is output

Goal isdetermined

Movement in accordance with the
trajectory(Speed can be adjusted)

Operator

Only Wide range trajectory plan

Wide range + Local trajectory plan
Start

Start

Simulatedmovement

Rough trajectory
based on the Wide range
trajectory plan

Obstacles

Detailed trajectory
based on the Local
trajectory plan

Goal

Obstacles are missed

Goal

Obstacles are avoided©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5） Implementation items (Operating system)

No.516

Measures to resolve the issues with the trajectory plan
The risk of collision increases with manual operation ⇒ Collision is avoided by means of the “Local trajectory plan”
Position in which the robot and the environment do not interfere with eachother (Each axis value is arranged)

Information on the robot
and environment• 3D model of the robot

Local trajectory plan

• 3D model of theenvironment

Arbitrary movement(Issuing instructions for the
position of the arm tip)
[Control of breakup rate][Past operating method]
There are times when the manipulator elbow moved in a direction notintended by the operator.
[Local trajectory plan]
As positions can constantly be changed in real time for avoiding
interference, the operator can focus on operating the arm tip.

Robot

Operator

Past operating method

Simulated movement

Past operating method
Local trajectory plan

Evasive maneuvering of the elbow

The elbow collides with the obstacles
Obstacles

The elbow
automatically avoids obstacles©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.517Pre-conditions for the mock-up tests• It is assumed that the 3-D model has been built up to a certain extent based on internal investigation. However, it isassumed that there are errors and unknown territories (Areas that have not been investigated) (The current
condition of Unit 3 is assumed).
• The objective of this development is to develop a remote operation system equipped with a function to avoid
obstacles with a multi-joint manipulator. “The work of removing interfering objects from the vicinity of the pedestal
opening by means of a dual-arm manipulator” will be taken up as the subject for verifying this technology. Please
note that this technology is intended for application to various other environments and robots in the future.
Therefore, the purpose of the mock-up tests is to verify and evaluate versatile (general) remote operation
procedures (workflows) rather than digging deeper into the method.
• As an example of remote operation procedures, “cutting” and “grabbing” will be incorporated into the flow, but they
will not be investigated further. (They will be consolidated as issues and will be studied in details separately.)[Items of this development that will not be investigated any further]• Planning of removal procedures using physical simulation, etc. so that the damaged structures inside thepedestal are retained. (Not included in the scope this time).
• The structure of the gripper for grabbing the target object and the method of grabbing (This time a simple
hand will be used for the test).
• Controlling the delivery of the cutter for cutting the target object (This time only the procedure until the cutter
makes contact with the target object is included in the scope).
• Selection of radiation resistant sensors and equipment (This time cameras and sensors available on themarket will be mounted).
• Applicability to single arm hydraulic manipulator (This time only the dual-arm motor operated manipulator will
be used).
•The focus will remain on developing an operation system for performing the work safely and efficiently without
letting the manipulator collide.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)
Mock-up test plan••

Test equipment with an axial configuration close to that of the interference removal equipment will be used. (Thelinear motion of the access rail is substituted by the forward movement of the trolley)
A scaled down mock-up (1/1.8) will be prepared in accordance with the ratio of the test equipment, as the workabilityof the interference removal equipment will be simulated.
Interference removal equipment[Under examination]

Manipulator x 2

Rotation mechanism
1/1.8

Access rail

Main
specifications[Remodeling of the mock-up test equipment ①]
In accordance with the actual equipment, apivot will be added (In order to position the
manipulator vertically while passing through the
opening)

Mock-up test equipment (Upper floor decontaminationequipment)

Manipulator x 2
External
appearanceof theequipment

No.518Trolley

Manipulator: 8 axes x 2 types
Rotation mechanism: 1
Access rail: 1 (Extension)

Manipulator: 8 axes x 2 types
Rotation mechanism: 1 (Additionally installed)
Trolley： 1 (Forward motion /Backward motion)[Remodeling of the mock-up test equipment ②]
In accordance with the actual equipment, thecrawler movement of the trolley will be handled
as the linear motion axis
(In order to simulate the linear motion of theaccess rail)
As the movement of the access rail thatapproaches from diagonally above will besimulated, the mock-up will be installedtilted 15°(The trolley moves forward on the ground)

Inside the pedestal
Interference removal equipment
Items to be removed

1/1.8

Pedestal
opening

Pedestal
opening©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)
Status of manufacturing the mock-up

No.519Work performed by the dual-arm robot inthe vicinity of the pedestal opening

In order to conduct the test under conditions that are close
to the actual environment, a 1/1.8 mock-up was createdbased on the 3D damage model of the inside of thepedestal obtained as a result of the Unit 3 PCV internal
investigation (2017).
(During the test lights will be turned off to simulate
darkness.)

External appearance of the mock-up (Pedestal opening)

3D damage model of the inside of thepedestal reproduced based on theimages from the Unit 3 Internal
Investigation conducted in July 2017

Mock-up of the damaged structures inside the pedestal(A tilted platform frame is present in the vicinity of the opening)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.520

Image from the pan-tilt zoom camera
used by the operator for monitoring

Mock-up test equipment
In order to simulate the interference removal equipment (Under examination), cameras were installed on
the mock-up test equipment.
•
Tip tool: Installed at 2 locations as the claws of the hand and the blade of the cutter will be positioned
from the horizontal and vertical direction.
•
Main body of the robot: A pan-tilt zoom camera was installed on top and 4 fixed corner cameras were
installed facing the 4 corners of the opening.
Although installing bird’s eye view cameras inside the environment would make it easier to perceive theconditions, the cameras were installed in this manner in order to simulate the difficult conditions without
bird's eye view cameras during the initial stages.

Placement of cameras on themain body of the robot

Hand tool
Image from the hand camera used by theoperator for monitoring

Image from the 4 fixed corner cameras used by the operator for monitoring(Installed so that the cameras face the 4 corners of the opening)

Claws of the hand

Cutter tool (Saber saw)

Image from the cutter camera used by the operator for monitoring
Blades of the cutter

Top left
Bottom left

Top right

Bottom right©International Research Institute for Nuclear Decommissioning

No.521

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items(Operating system)

Mock-up test conditions•

4 operators participated in the interfering objects removal tests 1 - 4 (Table below).
(A series of movements including entering the pedestal opening, approaching the item to be removed, grabbing,cutting, transferring and storing in collection container)•

The extent to which the operators can handle “errors” and “unforeseen incidents” set up in the mock-up while
operating the actual equipment (site) was verified without informing the operators beforehand about the “worst
case scenarios” in tests 2 - 4 (Comments such as “Various steps involving judgment should be incorporated
assuming actual work”, “Case studies should be conducted on structural changes and issues caused by thework itself” were reflected.)

The viability of work was verified and the trajectory data was created as “Advance planning” (simulation)
respectively for each test, and then “Actual operation” was performed at the site (illustrations on the right).
(However, if there are worst case scenarios, those cannot be handled with the trajectory data created during
advance planning. It becomes necessary to correct the environmental model on site and calculate the trajectorydata once again.)

Advance planning (simulation)
Each of the 4 operators were provided withlaptops and advance planning was carried out
all at once in the conference room.

•

Item to be
removedName ofthe test

Worst case scenarios (Operators not informed about
these beforehand)

Test 1

None

Test 2

Shift in the position of item to be removed (5cm)(Standard test in which the simulator and the actual
equipment in the mock-up are matched → The result is used
for calculating throughput)
Item to be removed
in Test 2
5cm deviation

Test 3

Assumption that a pipe that was at a distance camefalling towards the item to be removed

Test 4

Assumption that the structure that was at the back when
the test began, collapsed and came in front right aftergrabbing and cutting

Operation of the actual equipment (site)
Each operator operating the actual equipment
on site using the trajectory data created during
advance planning

Overview―

Item to be
removed in
Test 3

Pipe (moving)

Item to be removed in Test 4©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.522

Characteristics of Test 1••

Standard test
Without worst case scenarios: The simulator (environmental model) and the mock-up (actual equipment) are matched to the extent
possible. However, since there is deviation in the position due to movement of the crawler, position is adjusted as required. ## In the beginning, the start position had to be adjusted, and thereafter the position was adjusted at the discretion of the operator(Same for Tests 1 - 4)
Item to be removed in Test 1

Point of grabbing by the hand tool

Point of cutting with the cutter tool (2 locations)

Results of Test 1•••

All 4 operators successfully performed the operation.
All 4 operators spent around 1 hour on advance planning and 1 - 2 hours on actual equipment operation.
The throughput (positioning, retrieval work) was calculated based on the actual equipment operation by the 4 operators.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.523[Time: min: sec]
Goal setting

Results of Test 1

Trajectory calculation

All 4 operators successfully performed the operation

Trajectory verification
Trajectory execution
Manual operation
Positioning
Work transition

Actual equipment operation

Transfer outside
the opening

Grabbing
and cutting

Operator
A

Advance planning (simulation)

Time elapsed Time elapsed

Moving inside theopening

Operator
B

Operator
C

Operator
D

Grabbing
and cutting
Transfer outside
the opening©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval
Methods]

No.524

Goal setting① Remote controlled tip tools for retrieval (5) Implementation items (Operating system) Trajectory calculation
Trajectory verification

Results of Test 1

Trajectory execution

Work transition of the operator and approach distance(Log data is analyzed)

Work transition (The bar graph on the previous
page was changed to horizontal layout)

Robot moves＝ Approach
distance changes

Manual operation
Positioning
Work transition

0.8

Approach distance [m]⑬ Storing⑫ Transferring⑪ Rotating the grabbed object⑩ Verifying the status of grabbing with cutter tool
(Hand tool operation)

Grabbed object

Cuttertool

Grabbed object

Cuttertool

The margin value of 40mm (=0.04m) as per the trajectory plan was almost
retained.
As described later, Tests 2 - 4 had similar results.

0.1
0.04
Margin value
as per the0trajectory
plan 0⑨ Verifying the status of grabbing with cutter tool
(Hand tool operation)

While grabbing and cutting the approach, distancebecomes zero.
(As the system for avoiding collision with the target
object is turned OFF)

⑧ Verifying the status of grabbing with cutter tool
(Cutter tool operation)

locations)

Shift in approach distance
The solid line indicates robot operation inprogress, and the dashed line indicates simulator
work in progress)⑦ Verifying the status of grabbing with cutter tool
(Cutter tool operation)

2⑥ Lifting up the grabbed object⑤ Cutting (0.2④ Grabbing

0.3③ Approaching the target object

0.4② Moving inside the opening

0.5① Moving to the front of the opening

0.7
The starting point does
not match the graph as
the time at which data
was recorded and thetime of start of work
were different. 0.6

The work took time as this was
an operation characteristic to
the actual equipment operation

1000

2000

3000

proximity[m]4000_proximity[m]

5000

6000

Elapsed time [sec]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.525Characteristics of Test 2•

Test that requires lot of efforts•
Since the grabbing point is located between 2 cutting points, “cutting at 2 locations while grabbing” cannot be accomplished.
→ Cutting is performed at the first location first, and then after withdrawing outside the opening, the upper and lower arms areinterchanged and grabbing + cutting of the second location is performed.
Item to be
removed in Test 2②

Point of grabbing
by the hand tool

Hand tool
Moving inside the opening

The cutter tool is placed on
the upper arm

Interchanging theupper and lower arm

Moving inside theopening once again

Hand tool
grabbing thetarget object①
Point of cutting with thecutter tool (2 locations)①② show the cutting
sequence•① Firstcutting point

The cutter isplaced on thelower arm

Cutting at the first location② Second cutting point

Since the opening is small, the arms
need to be withdrawn tentatively and the

Grabbing and cutting at the second

upper and lower arms are interchanged.

With worst case scenarios: The item to be removed is set up in the mock-up (actual equipment) at a position that is 5 cm away from its locatioin the simulator (environmental model). The operators were made to participate in actual operation without being informed about this.

The item to be removed is placed at a
position that is 5 cm away (white
marking) from its location in thesimulator.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)[Time: min: sec]

Results of Test 2•••

Operators B and D moved the hand too
close to the target object while
performing the grabbing action andpushed down the target object. (During
the grabbing movement, the collision
avoidance system of the hand is turnedOFF) → The administrator restored thetarget object and the test was resumed.
Operator B let the elbow of themanipulator collide with opening eventhough the collision avoidance system
was ON. → Details are described later.
The administrator informed the operator
about the collision and the test was
resumed.
In the case of Operator D, a collisionoccurred inside the robot (tip tool and thecarrier). Restoration took time. (This wascaused by an error in the setup by theadministrator).

Collision with thetarget object
Collision inside therobot

Successful

Successful

Transfer outside
the opening

Work transition
Grabbing andcutting (2)Advance planning (simulation)•

The worst case scenarios did not have
any impact. (The deviation of about 5cm
is corrected by adjusting the position)

Collision with the target object
Collision with the opening

Goal setting
Trajectory
calculation
Trajectory
verification
Trajectory
execution
Manualoperation
Positioning

Actual equipment operation•

Operators A and C performed theoperation successfully.

No.526

Moving outside theopening andinterchanging theupper and lower arms

Cutting (1)Moving inside
the opening

Operator
A

Operator
B

Operator
C

Operator
D

Cutting (1)Moving outside theopening andinterchanging theupper and lower arms

Grabbing andcutting (2)Transfer outside
the opening©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.527

Characteristics of Test 3•

Simple test using the simulator•

With worst case scenarios: The pipe that was at a distance in thesimulator (environmental model) was moved in the mock-up(actual equipment) to a position such that it gets in the way of
the grabbing point. (Assuming that the pipe came falling), →Whether the operator is aware of the environment, and what hedecides to do thereafter is verified.

Layout of the simulator

Item to be removed in Test 3

Point of grabbing by the hand tool
Point of cutting with thecutter tool (1 location)

Layout of the mock-up

Test being conducted

Item to be removed in Test 3
Item to be removed in Test 3

Pipe(At a distance)
Pipe (moving)©International Research Institute for Nuclear Decommissioning

No.528

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

Removing the pipe that becomes an obstacle
in approaching the item to be removed

Results of Test 3••

Operator A pushed down thetarget object with the hand while
performing the grabbing action(the collision avoidance system of
the hand is turned OFF during the
grabbing action). → The
administrator restored the target
object and the test was resumed.
The Operator B did not notice thepipe and let the hand collide withthe pipe. → The administrator
informed the operator about thecollision and the test was
resumed.
Operator B let the elbow of themanipulator collide with the
opening even though the collision
avoidance system was ON. →Details are provided later.

Removing the item to be
removed as planned

Successful[Time: min: sec]

Transfer outside theopening

Collision with the pipe
Collision with the
opening

Grabbing andcutting

OperatorA

Moving inside theopening

Advance planning (simulation)•

Operators C and D performed theoperation successfully. However,Operator C removed the item tobe removed and Operator D
removed the pipe that became an
obstacle (Each operator decided
to act differently).

Actual equipment operation•

Successful

Collision with the target object

Operator
B

Operator
C

Operator
D

Goal setting
Grabbing andcutting

Trajectory
calculation
Trajectory
verification
Trajectory
execution
Manual operation

Transfer outside theopening

Positioning
Work transition©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.529Characteristics of Test 4•

Simple test using the simulator (Simplest amongst Test 1 - 4)•

With worst case scenarios: It is assumed that the structures that were at a distance (at the back) when the test started
collapsed and came in front right after grabbing and cutting the target object (pipe) (The test is stopped temporarily, theadministrator changes the position of the structures so that the operator cannot view them.) → Whether the operator is awareof the environment, and what he decides to do thereafter is verified.

As compared to Test 3 in which the complete picture was possible to be verified before grabbing and cutting, in Test 4, since
the environment changes while the operator is still holding the pipe, the operator cannot move the robot freely and has to perceive
the environment with the information obtained from a narrow range of view.
Layout at the start of the test

Structure(At a distance)

Layout after grabbing and cutting
Item to be removed in Test 4（With the pipe held with the hand tool）

Item to be removed in Test 4

Structure(Is moved)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

Transferring after locating the structures basedon the point cloud and the camera images

Results of Test 4[Time: min: sec]••

Operators C and D
located the structuresusing the point cloud
and then performed
transfer work.

Quitting the use of the point cloud for locating thestructures and relying only on camera images fortransfer

Actual equipment operation•

All 4 operators successfully performed the operation

All operators
successfully performed
the operation.
Operators A and B
gave up using the point
cloud for locating thestructures and relied
only on camera images
for transfer work.

Transfer outside theopening

Grabbing andcuttingMoving inside theopening

Trajectory
calculation
Trajectory
verification
Trajectory
execution
Manual operation
Positioning
Structure B
collapsed
Work transition

Advance planning (simulation)

Goal setting

No.530Operator
A

Operator
B

Operator
C

Operator
D

Grabbing andcutting

Transfer outside theopening©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.531

Summary of test results⚫ 4 operators participated in the interfering objects removal mock-up test using the operation system (trajectory
planning) that has been developed. It was verified that a series of tasks was feasible in a confined environment
such as the pedestal opening due to the collision avoidance function of the operation system. Also, it was verified
that gaps (errors) between the simulator and the actual site or unforeseen incidents can be handled by using theposition adjustment function.
⚫ The importance of position adjustment and the necessity of collision avoidance while performing the grabbing
action were clarified through the mock-up tests. Also, the work items that the operators took time to perform wereverified as well.
Tests 2 - 4 were worst case scenario tests. The purpose of these tests was to find out the limit up to which the operation system can be used.
Items to be
removedName of the
test
Test 1

Worst case scenarios (Operators not informed about these beforehand)

None(Standard test in which the simulator and the actual
equipment in the mock-up are matched → The result isused for calculating throughput)

Test results

Remarks

All 4 operators successfully
performed the operation

The work was completed in 1 - 2 hours which was
satisfactory.
・The shift in location did not have any impact
・There is a risk of collision as the collision
avoidance function is turned OFF in order to let
the hand approach the target object while
performing the grabbing action.

Test 2

Shift in the position of item to be removed (5cm)

2 operators successfully
performed the operation
There was collision in the case of
2 operators

Test 3

Assumption that a pipe that was at a distance came falling towards theitem to be removed

2 operators successfully
performed the operation
There was collision in the case of
2 operators

・One of the operators did not notice themovement of the pipe which led to a collision.
・There was individual difference in judgment.

All 4 operators successfully
performed the operation

All 4 operators appropriately ascertained thechange in environment based on partial
information.

Test 4

Assumption that the structure that was at the back when the test began,collapsed and came in front right after grabbing and cutting©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.532

Results and considerations ①•

Collision accidents occurred 6 times during the 16 rounds of mock-up tests (4 operators x Tests 1 - 4)
• Pushing down of the target object with the hand tool … 4 times (The remaining 2 times were caused due to lateral slip
caused by the crawler movement: Described on the next page)The camera screen that the operator was focusing on while performing the grabbing action with the hand tool
Hand tool

Claws of the hand

Test 2 Operator D

Test 3 Operator A

Collision with the hand

Collision with the claws of the hand

[Cause] The operator did not get a sense of the
distance and went too close to the target object[Cause] If you focus on one place, thesurroundings are not visible

There is a risk of collision as the collision avoidance fuunction is turned OFF in order to let the hand approach the target object while
performing the grabbing action.
[Countermeasures]① A mechanism that can accurately and precisely measure the approach distance should be used or grabbing mechanism for following theother person by roughly adjusting the position should be used.
② A support technology for complementing the visual perception characteristics of human beings should be developed.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.533Results and considerations ②•
The manipulator (elbow) coming in contact with the opening … 2 times (Both instances occurred in the case of Operator B)→ Although the interference avoidance function was ON, the lateral slip caused by the crawler movement led to these incidents.
Characteristics of the operator B： ① High acceleration and deceleration speed → The crawler was likely to deviate easily (There was a lot of forward
and backward movement during tests 2 and 3 in which the incident of contact occurred)② Position was not adjusted appropriately after the crawler moved → The gap was unable to be corrected
It is believed that this issue can be resolved if the position is adjusted appropriately. (In the actual equipment, since the movement is over the rail, lateral slip
does not occur)⇒ [Conclusion] Manipulator interference can be avoided by appropriately adjusting the position.
The result of measuring the extent of lateral slip at the time of completion as against
the position in the beginning with the help of motion capture cameras during Test 3,
and comparison with the pedal operation

Operator

Lateral slip [cm]

B

3.2

C

1.5

D

1.8

〇: Motion capture cameras

Vertical axis: Extent of stepping on the pedal （0 - 1) (Horizontal
axis: Time elapsed during the test)

Operator B stepped much harder on the pedal ascompared to Operators C and D.
＝ Higher speed of operation
And high frequency of pedal operation⇒ It is believed that this led to a larger crawler deviation

Operator A did not obtain any data.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)

No.534

Results and considerations ③•

Based on the analysis of the mock-up test results, it may be possible to further shorten the time required.
•
In the advance planning (simulation), a lot of time (30%) was required for “Goal setting”.
→ If there is an automatic position adjustment function to adjust the position with respect to thetarget object, the time required can be shortened.
(There was a comment from the operators that “It is difficult to make fine adjustments using
the mouse”.)•

Setting of goals

While operating the actual equipment, “trajectory execution”, “manual operation” and “position
adjustment” using the robot comprised a higher proportion of the time.
→ If “manual operation” and “position adjustment” are made semi-automatic, it may bepossible to shorten the time required.

⇒ [Conclusion] It may be possible to further shorten the time required by means of automation.
Goal setting: 33%

Position adjustment
Goal setting
Trajectory
calculation
Trajectory
verification

The proportion of time that
“trajectory execution” comprises
is quite large as well, but as thetime required has already beenshortened by using the method ofregenerating trajectory data
during pedal operation, it isbelieved that further
improvement would be difficult.

Trajectory
execution

Position adjustment: 16%

Manual operation
Positioning
Work transition

Manual operation: 24%
Ratio of time required for work in theadvance planning (simulation)(Average value for 4 operators
participating in Tests 1 - 4 )Ratio of time required for work while operating the actual
equipment (site)(Average value for 4 operators participating in Tests 1 - 4 )©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.535① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)✓ Contribution of the results towards the reflection destinations[Outcome]: Automation of interference avoidance by the manipulator.
[Reflection destination]: Development will be carried out assuming the outcome will be used in the remotecontrolled robot for fuel debris retrieval, but application to various other works and robots in the future will be
aimed for. (The environment model and the robot model will be modifiable).
[Contribution]: Enhancement of safety and efficiency of work can be expected.## With the operational support resulting from the previous research “Development of techniques for supporting remote operationin environments with low visibility and narrow spaces” implemented in FY2019-20, there has been a reduction of approx. 90% in thetime required for manual operation by veteran operators, and a reduction of approx. 80% in the time required for creating teachingdata. The previous project will be implemented and advanced further in the current project.

✓ Analysis from the viewpoint of applicability to the site
• Site applicability is verified by confirming the viability of the series of operations using the remote controlled
system including the mock-up simulating the actual site and the element test equipment, and points ofimprovement are identified.
• A system which is highly applicable to the site is developed in cooperation with the Fuel debris retrieval
monitoring/support/integrated management WG, while incorporating the comments from site operators
participating in the mock-up tests and experts in manipulator technology.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]

No.536① Remote controlled tip tools for retrieval (5) Implementation items (Operating system)✓ Level of achievement compared to the goals
Accomplishment of all the following items (Implemented through the mock-up tests)• Test manufacturing of the operation system• Study of grabbing/cutting/transfer of interfering objects• Verification of the viability of a series of operations• Acquisition and consolidation of actual data on work procedures• Creation of data for throughput evaluation• Consolidation of case studies on the operation system application conditions, assumed issues, etc.

©International Research Institute for Nuclear Decommissioning

No.537

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(6) Development schedule[Legend] Planned:
FY2021

Actual:FY2022

Study items
4
Major milestones

5

6

7

8

9

10

11

Interim Report
▼

12

1

2

3

4

5

6

Interim Report
▼

7

8

9

10

11

Interim Report
▼

12

1

2

Final Report

Study of throughput
improvement measures
Tip tool element testplanning andpreparation
Element tests(Processing tests forthroughput evaluation)

Time required forprocessing interfering
objects and fuel debris

Study of operation
systemDevelopment of theoperation system andsimulation verification

Time required for manipulator work
(Time required for moving, positioning, etc.)

Element tests (Series ofoperations using theoperation system)
Throughput evaluation
Creation of report

Remarks

A panel of experts met on July 13, 2021 in connection with the operation system.
A panel of experts met on February 8, 2022 in connection with the operation system.
A panel of experts met on August 26, 2022 in connection with the operation system.
A panel of experts met on February 8, 2023 in connection with the operation system.
©International Research Institute for Nuclear Decommissioning36. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tools for retrieval(7) Summary

No.538

Tip tool➢ Processing tests were conducted using tip tools that consider the specifications of access equipment,
and prospects of application of those that had issues to actual equipment were obtained. Also data forthroughput evaluation such as processing time, life of blades, etc. was refined.
➢ Throughput was evaluated using the above-mentioned data for throughput evaluation, and was further
refined.
➢ Requirements of the robot arm in terms of the processing reaction forces (blade pressing, blade rotation)
were obtained through processing tests.
➢ Measures were planned in response to the issues that became evident as a result of the processing
tests.

Operation system➢ 4 operators participated in the interfering objects removal mock-up test using the operation system(trajectory planning) that has been developed. It was verified that a series of tasks was feasible in aconfined environment such as the pedestal opening due to the collision avoidance function of theoperation system.
➢ The importance of position adjustment and the necessity of collision avoidance while performing the
grabbing action were clarified through the mock-up tests. Also, the work items that the operators tooktime to perform were verified as well.
➢ Items for further improving safety and efficiency of work in the future were selected from the issues
identified through the mock-up tests conducted this time.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This ProjectNo.5392) Development of top access method(1) Development of technology for realizing the concept of retrieving large structures① Method of cutting large structures
With respect to retrieving fuel debris and reactor internal structures, in order to enhance thethroughput using the top access method, the method of transferring unitized large structures is being
studied as part of the development being undertaken since FY2019. For establishing that method,
structures need to be cut out and transferred. However, during the work of cutting out, reactor
internal structures that comprise a variety of equipment from steam dryer to sparger, shroud, jetpump, etc. need to be cut in a high-dose radiation environment and in a confined space inside thereactor, and transferred. Also, the method of cutting and transferring large structures other than thereactor internal structures such as PCV head, RPV head, etc. under a high-dose radiation
environment, in order to access the inside of the reactor, needs to be studied.
As it is presumed that the fuel has melted and is present inside the RPV, a method of cutting andseparating while taking into consideration metallic reactor internal structures and ceramic fuel debris,will be studied, and element tests will be conducted using simulated test pieces. Also, the method oftransferring structures after they have been cut, including PCV head, etc. until the structures areloaded on to the large transfer equipment, will be studied, and its site applicability will be evaluated.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept
of Retrieving Large Structures]① Method of cutting large structures

No.540

Table of Contents
⚫
⚫
⚫

⚫

Development results related to the top access method achieved so far and correlation with this project
Issues, implementation details and results
Concept of the method, and the main equipment (passageways, additional building, work container,etc.)
Basic approach towards transferring the structures and the steps involved in this method⚫

Method of cutting reactor internal structures into large
pieces Development policy⚫
Scope of application of filling and solidification⚫
Method of cutting reactor internal structures into large
pieces・Study conditions
・Study on the course of cutting・Selection of cutting method
・Element test details(Test equipment, parameters, items)
・Element test results⚫
⚫

Development schedule
Summary⚫

Study on filler material
・FY2020 results
・Identification of study items
・Barrel injection test
・FY2021 results and FY2022 implementation items
・Measures by increasing the amount of filling of silica
sand・Test using a 200L barrel
・Extension work (Joint placement test)
・α rays irradiation test・Study of the method of controlling outflow from thethrough hole・Study of the method of filling filler material inside thereactor©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept
of Retrieving Large Structures]① Method of cutting large structures

No.541Development results related to the top access method achieved so far and correlation with this project are indicated below.
Project of Development of Upgrading of Fundamental technology (Implemented in
FY2017-18)[Study of the method for finely cutting inside PCV]➢
Implementation of element tests using simulated reactor bottom
structures➢
Estimation of throughput, identification of issues

CRDハウジング
CRD
housing
クランプ部
clamp
part

Upper lid
Being developed
under the Ensuring
Safety PJ

Container
dual lid

Large transfer
container

To be developed aspart of this project

Ensuring Safety Project (Implemented in
FY2020-21)

Method of transferring unitized large
structures[Feasibility verification of the large transfer container lid]➢
Development of the air tight mechanism for the container lid and element
tests➢
Study of the method of criticality control after storage in containers (duringtransfer)
Isolation Technology Project(Implemented in FY2021-22)

Scope of studies
conducted in this project[Development of isolation technology to prevent the
spread of contamination]➢
Development of isolation technology andelement tests

Connection sleeve(Connecting the PCV
and the passageway)
Structures otherthan the reactor
internal structures(PCV head, RPV
head, etc.)

Reactor internal
structures (Dryer,
separator, shroud,fuel debris, etc.)

Items to be studied in future➢Work
container

Lower lid

Large transfer
container[Development of technology for realizing the concept of retrieval]➢Study of the method of cutting large structures➢
Study of large transfer containers (Main body)➢
Study of large transportation equipment

Transportation cart

Method of fine cutting

Project of Further Increasing the Retrieval Scale of Fuel Debris (Implemented
in FY2019- 20)

This project

Shielding cart

the reactor bottom

Movable flange[Study of the method of transferring the unitized structures]➢
Implementation of element tests related to disassembling
the reactor bottom➢
Conceptual study related to the large transfer containers➢
Study of the method of criticality control until storage incontainers

AWJ
nozzleAWJノズルRemoval of large structures at
炉底部の大型構造物の撤去

Study of developmental issues identified during engineering andtechnical development, etc.
Isolation
sheet
隔離シート

FY2019-20 Study on cutting
the reactor bottom andimplementation of element
tests©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.542Retrieving Large Structures]
Development of technology① Method of cutting large structures
pertaining to items in red will be
carried out in this project

Development results related to the top access method achieved so far and items to be developed in this project are indicated below.
Method of cutting large pieces

走行
Disassembly
解体装置
equipment

Crane
for handling
切断片取り
cut扱い揚重機
piecesRollerPin

Plate

Main body of frame

Drive motor
駆動モータ(連絡通(Outside路外）the passageway)

Disassembly
解体装置
equipment

Disassembly
解体装置
equipment

Center plate Endless roller

Hoisting
切断片吊accessories
forり具
the cut pieces

Shroudシュラウド
ヘッドボルトheadbolt

Endless roller system

RPV
upper lid
RPV上蓋
Cutting
切断マニ
manipulator
ピュレータ
ＰＣＶ上蓋
PCV
upper lidCutting
切断マニピュレータ
manipulator

Cutting
切断マニピュレータ
manipulator

Isolation sheet
Separator
セパレータ

Development of isolation technology to preventthe spread of contamination (FY2021-22)

Stud
bolts
スタットボルト

Implementation of conceptual study of the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)

Isolation sheet

Method of cutting structures other than reactor
internal structures

Guide
ガイド
Trapezoidal
台形ネジ
screw

Trapezoidal screw drive
system

Implementation of conceptual study of the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)

Large transportation equipment

Air tight mechanism with dual lid
Method of cutting the reactor internal structures
Shielding cart

Transportation cart

Dual lid

Illustration of filling and cutting
Shroud gripper(Making a hole and grabbing)Cutting (2)Cutting ①

Work container

ShroudCutting the entire cross sectional area
Wire saw cutter
シュラウド把持部（穴加工し把持）Container dual lid

Large transfer container

Cutting ②
シュラウド

切断②

Solidification
by filling
断面全域の切断

ワイヤー

Element tests for the Ensuring Safety PJ (FY2020-21) are being planned

切断機

Cutting structures at the reactor bottom

Large transfer container

Cutting tool
切断ツール
transportation
搬送装置
equipmentCollection
回収容器
container
搬送装置
transportationequipment

補助アーム
Auxiliaryarm

Auxiliaryarm

Fuel debris at thereactor bottom

グレーチング
Grating
insulating
保温材
material

Cutting
tool (With
切断ツール
grabbing and(把持と切断機能あり)
cutting functions)

7m

RPVRPV下鏡
lowerhemispherical dome

Lowerhemisphericaldome opening

CRD.Hサポート
CRDH
support
ビーム、ブラケット
beam,bracket

HCL
pipes
HCU配管

Simulation of collapsed CRGT

Filled with geopolymer(Inner diameter of container 300mm

Implementation of element tests pertaining to the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)

Signal cables

信号ケーブル類

Illustration 炉底部干渉物撤去作業イメージof the work of removing interfering objects
from the reactor bottom

Implementation of element tests pertaining to the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)

Φ6m
Φ7m
Implementation of conceptual study of the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.543
Retrieving Large Structures]① Method of cutting large structures
Crane[Issues]•
Structures need to be cut and transferred in a high-dose radiation environment and in aconfined space.
Passageway•
The methods for cutting and removing structures other than the structures at the reactor
bottom (reactor internal structures in the reactor core, PCV/RPV head, etc.) need to bestudied and their feasibility needs to be verified.
•
The feasibility of the methods for lifting up the cut structures up to the passageway
Scope of studies
needs to be verified.
conducted in this project
Connection sleeve[Implementation details](Connecting the PCV
and the passageway)
・Preconditions for the studies will be consolidated.
・Method and procedures for cutting and transferring reactor internal structures andStructures other thanstructures other than the reactor internal structures will be studied.
reactor internal
・With the method of filling, solidification and then transfer of fuel debris in mind, thestructures
methods for cutting and separating structures that are a mixture of metallic and ceramic(PCV head, RPV head,etc.)
material including the filler material will be studied for retrieving reactor internal⇒ Element test results
structures, element tests will be planned and implemented, and feasibility will be verified.
have been reported
・ The methods of cutting large structures such as the PCV head, etc. will be studied
under “Accomplishment
based on the studies on the connection sleeve to which structures other than the reactor
Report for FY2021*”)internal structures are joined inside the reactor well, element tests will be planned andReactor internal
implemented, and feasibility will be verified. (Reported under “Accomplishment Report forstructures
FY2021*”)(Dryer, separator,
・ The methods for transferring structures after they have been cut, including the PCV
shroud, fuel debris, etc.)
head, etc. until the structures are loaded on to the large transportation equipment, will be
studied, and their site applicability will be evaluated.

[Expected outcome]•
Presentation of methods for cutting reactor internal structures.
•
Presentation of the methods for loading structures after they have been cut on to
the large transportation equipment.

*Accomplishment Report for FY2021: https://irid.or.jp/wp-content/uploads/2022/08/2022007_deburitoridashi.pdf

FY2019-20
Study of methods for cutting the reactor
bottom and implementation of element tests©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.544Retrieving Large Structures]① Method of cutting large structures
The development for the method of cutting large structures has been carried out by dividing it into the items, (a) - (c).
The status of studies (results) and the contents of the report this time are as indicated below.
Reported in this
Item
no.

②

③

Status of studies (Results)

Contents of the report(a) Method oftransferring large
structures in their
entirety

The results of the studies conducted on methods fortransferring unitized large structures, including the methodof application of the isolation sheet that is being
implemented in another subsidy project (Isolation
Technology PJ*) were consolidated.

Results of the conceptual
study and overall steps(b) Structures otherthan reactor
internal structures

The methods for cutting the stud bolts of the RPV headfrom among the structures inside the reactor well werestudied, and element tests were implemented.

Reported under“Accomplishment Reportfor FY2021*”(c)Conceptual study pertaining to the methods for cutting
reactor internal structures, and element tests wereconducted.

Test results report

Large transfer container

Large transfer containers were test manufactured, element
tests were conducted for verifying air-tightness whencombined with the dual lid test manufactured during the
Ensuring Safety PJ.

Conceptual study results
and test results report

Reported in
Section ②

Large transportationequipment

A comparative evaluation of the drive systems for the largetransportation equipment was carried out, the motoroperated connnector system was selected, and element
tests were conducted.

Conceptual study results
and test results report

Reported in
Section ③

Method of cutting large structures①

Implementation items

section(Section ①)

Reactor internal
structures*Isolation Technology PJ： “Development of fuel debris retrieval method (Development of isolation technology to prevent the spread of contamination during retrieval and transportation of large
structures)” PJ*Accomplishment Report for FY2021: https://irid.or.jp/wp-©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.545Retrieving Large Structures]① Method of cutting large structures[Preconditions for the methods for transferring large structures in their entirety]✓

Preconditions for the study on methods for transferring unitized large structures are indicated in the table below.
ID.

Pre-conditions

Evidence

Remarks

1

An additional building for the top access method should beinstalled in addition to the additional building for the side
access method.

In the case of the top access fuel debris retrieval method,transferring the unitized structures is being considered.
Hence it would be difficult to use the delivery equipment
in common with the side access fuel debris retrieval
method.

Whether or not 1 additional building canbe used in common for the top and side
access equipment needs to be studied
through separate engineering.

2

A frame structure should be installed so that the load of thepassageway in which retrieval equipment, etc. will be
installed is supported by the ground surface.

Considering the acceptable maximum load of theoperation floor, it will be difficult to support the load of thepassageway.

3

After transferring the unitized RPV head, the load of theretrieval equipment can be placed on the surface of the RPV
head flange.

At the current stage, since the RPV head is being
supported, it is assumed that load can be placed after the
RPV head is retrieved.

4

The load of the retrieval equipment can be placed on the
support for the load of existing structures inside the RPV(including on top of the structures).

As the collapse of the existing structures has not beenverified at the current point in time, it is assumed that theload support can be used.

5

The method for transferring as largest a size as possible
should be considered.

As the status of damage has not been verified, the study
should be conducted with a large size which is the mostdifficult to handle.

6

Existing hanging metal fittings can be used while transferring
structures.

Since the structures that are taller than the separator
have not reached their melting point according to theresults of existing analysis, it is assumed that hanging
metal fittings can be used.

7

Cutting policy of connecting parts such as bolts, etc. should
be considered.

The cutting policy should be studied considering thepossibility that connecting parts such as bolts, etc. may
not turn due to deformation, galling, etc.

8Large transfer containers should be used for transferring
structures.

The policy of preventing spread of contamination should
be maintained by using large transfer containers.

The transfer dimensions will be revised
depending on the status inside thereactor.

Whether the bolts should be cut or
loosened needs to be evaluateddepending on the actual conditions.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.546Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Concept of the method, and the main equipment]✓

The work of cutting and transferring fuel debris and structures is implemented inside the PCV using disassembly equipment installed in the work
container (access equipment inside the PCV) or a crane. The fuel debris and structures are retrieved in the form of large unitized structures without
cutting them finely as far as possible.

✓

The retrieved large unitized fuel debris (structures) is stored in large transfer containers inside the additional building, and transferred within thepremises. Further, structures (shield plug, RPV head, etc.) that are larger than the large transfer containers are cut and divided inside the additionalbuilding.

✓

The isolation sheet* is installed at the bottom of the work container and on top of the well for controlling spread of contamination while disengaging
the work container.

No.

Equipment name1

Passageway

2

Crane

3

Work container

Specifications and functions

Passageway

Crane• Connects to the PCV and forms the primary boundary• Confinement and shielding of radioactive materials

Workcontainer

Lifting of work equipment (Does not have a transportation function)• Installed on the floor surface of the passageways and on the RPV flange
surface, etc., and ensures shielding thickness required while lifting theinternal disassembly equipment, and during the work of storing andtransferring fuel debris and waste.

4

Isolation sheet

Spread when the work container is hoisted, cut out to form a sheet on theboundary surface between the passageway and the PCV to control the spreadof contamination to the passageway when the work container is disengaged.

5

Transportation cart

Transportation of equipment, fuel debris and structures (radioactive waste)
between the additional building and the passageways.

6

Shielding cart

Shields the top of the reactor well when the work container is disengaged.

7

Large transfer container

Stores and transfers the structures (fuel debris) transported from inside the
PCV.

Isolation
sheet
Shieldingcart(Section ③)

Transportation cart
(Section ③)(Refer to Section ③)(Refer to Section ②)

Large transfer
container(Section ②)

Detailed studies and element tests related to the isolation sheet were carried out as part of the Isolation Technology PJ (“ Development of fuel debris retrieval method*(Development of isolation technology to prevent the spread of contamination during retrieval and transportation of large structures)” PJ).
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.547Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Results of studies related to the passageway]✓✓✓

The mass of the passageway is several thousand tons and thus there is enormous load on the existing R/B. Hence studies wereconducted assuming that a gantry would be installed in the area surrounding the R/B and the passageway would be installed on topof said gantry.
The height of the passageway was reduced except for the well by making use of cranes. The height over the DSP was further
reduced (approx. 5m) by ensuring that only the shielding cart is carried over it.
The site boundary dose was assumed to be 10μSv/year, and the shielding thickness was re-calculated. The required shielding
thickness was 58mm for the passageway and 250mm for the work container. The passageway together with the ancillary equipment
were expected to be approx. 5600ton.

[Passageway specifications]
Items

Specifications

Function• Confinement ofradioactive materials• Shielding of radiation

Size

EW23 x NS46 x H18m

Mass

Approx. 5600 ton(Including equipment)

Approx. 18m

Approx. 5m

Passageway

Approx. 20m

Approx. 5m

N
Crane room
(Houses the main body of the crane)

Crane frame
Reactor Building

Passageway

58mm

Work container

250mm

Shieldingthickness

Illustration of the external appearance of the passageway
Note) The length of the passageway in the NS direction includes only the upper part of the R/B and does not include the length of the gantry.
Hence, the mass of the retrieval cell will increase depending on the size of the gantry.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.548Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Method of connecting the passageway and the PCV]✓✓The displacement between the old operation floor and the passageway is absorbed by inserting the outer peripheral cover(installed between the old operation floor and the passageway) into the drain pipe (water seal / installed on the oldoperation floor side).
The PCV, well, passageway and the outer peripheral cover form the primary boundary.
: Primary boundary

Building cover

Building cover

Welding

Passageway

Passageway

Upper edge of the outer
peripheral cover is weldedto the passageway
Outer peripheral
cover

Outer peripheral coverOuter peripheral
cover

Outer peripheral cover

Water seal

GantryOuterperipheral
cover

Lower edge of the outer
peripheral cover is installedinside the water seal

The outer peripheral cover is installed frominside the retrieval cell

GantryCable trench

300

Outer peripheral
cover

Pool curve

300

Building cover▽ Old operation floor

R5924.5
Outer peripheral
cover

Outer diameter of the uppermost partof the shield plug

Water seal (drain pipe)(Newly installed)

Illustration showing the carrying in and installation of the outer peripheral cover(A pattern for carrying-in while installing the passageway is indicated as well)

R/B
Schematic view of the structure of the primaryboundary©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.549Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large
structures[Results of studying the layout of the additional building (1/3)]✓✓✓

The retrieved large unitized structures and fuel debris from inside the PCV will be
stored in large transfer containers and transferred.
For transfer using large transfer containers, work of closing the lid and the work of
breaking up some of the structures (structures that are larger than the innerdiameter of the large transfer container) are required. In addition to these works, inorder to perform maintenance work on the transportation cart or the work
equipment used inside the PCV, an additional building is required adjacent to theReactor Building (R/B)
R/B.
The layout of the additional building was studied considering the required work processes and the size of theAequipment/facilities.
800ton cranePassageway

Additional building

Crane
Carrying-in
anterior
chambercellCart maintenance cell

Structure
breaking up
cell

Dual lid
Dual lid hoisting
opening/closing cell accessory

maintenance cell

Dual lid

Container
outer lid
installation /removal cell

Truck
lock

Processing
equipment
maintenance cellNewbuilding

Large transfer containerA

A-A cross section

Results of studying the layout of the additional building: Transfer line for large unitized structures©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.550Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Key for the arrows indicating the transfer line][Results of studying the layout of the additional building (2/3)]： Line for carrying in equipment, etc.
： Transfer line for structures that are Φ6m or larger： Transfer line for structures that are Φ6m or smaller： Line for decontamination and maintenance of equipment, etc.

A
Φ6m
or larger

Φ6m
or smaller

To the largetransfer container

Cart
maintenance cell

To thedecontaminati
on cell

Carrying-in
anterior
chamber cell
Φ6m
or smaller

Decontamination cell
service entrance

Shield plug
service entrance

Φ6m
or smaller

To the maintenance cell

To themaintenance cell

Processing cell
service entrance

Φ6m
or larger

Structuredivision cell *1

Processing
equipment
maintenance
cell

Φ6m
or larger

Newbuilding

Large transfer containers

Carrying in equipment, etc.
Carrying-in
anterior
chamber cellA

Equipment
maintenancecell

A-A cross section*1 Details of work carried out in the structure division cell:・ Cutting of structures (Φ6m or larger) (Saw, laser, AWJ, etc.)
・ Transportation of structures that are cut to pieces that are Φ6m or
smaller and their storage in large transportation containers.
(Assuming that an overhead crane is used.)

Results of studying the layout of the additional building: Transfer line for large unitized structures (other than shield plug)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.551Retrieving Large Structures]① Method of cutting large structures：(a) Method of transferring unitized large structures

Shield plugtransportation(9 units)[Results of studying the layout of the additional building (3/3)]
Temporarily
stored in two 3
layer stacks(6 units)

Temporarily
stored in one 3
layer stacks(3 units)

Processing
cell

Carryingin anteriorchambercell

Processing
equipment
maintenance
cell

A

Cart
maintena
nce cellShieldplug

A-A cross section (Transfer to the processing cell)

Shield plug service
entrance(Closed after transporting
all units)

Processed to a sizethat can fit in thelarge transfer
container

Shield plug,
well closing lid
serviceentrance

Carryingin anteriorchambercell

Processing
equipment
maintenancecell

Carryingin anteriorchambercell

Equipment
maintenance
cell

Large
transfer
containerNew
buildingA
A-A cross section (Transfer after processing)Results of studying the layout of the additional building: Transfer line for shield plug
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.552Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Results of the conceptual study related to work containers]✓

The work containers should be of the same height and diameter as far as possible. The inside of the containers for processing andthe containers for transfer needs to be configured differently. The containers should be dedicated to the respective functions. Since
the reactor core and the reactor bottom are heavier as compared to the reactor internal structures, large cranes need to be used.
⇒ Arrangements are made for 3 types of work containers in all.
✓ The location where the work container is installed changes depending on the target object to be retrieved (From the perspective of
reducing the lifting height of the crane).
List of locations where the work container is installed with respect to the items to be transferred and the work containers used.
Items to be transferred

PCV head, RPV head insulating material,
RPV head

Height at which work
container is installed

On the operation floor (floor surface of thecell)Dryer, separator, FDW/CS, etc.

Work container (At thetime of cutting)Work container (At thetime of transferring)

Reactor core and reactor bottom

RPV flange surface
Work container ①
Work container ② (For transferring heavy
weight objects)

Work container ①’
Work
containerWork
containerWork
container

Section to be
retrieved

Section to
be retrieved

Image illustrating
installation of work
container
Section to
be retrieved©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.553Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Results of the conceptual study related to work containers]✓ Configuration of the 3 types of work containers used for the unitized transfer method is given below.
*The crane room has been excluded
Work container ①

Work container ①’

Work container ②

Crane

Cableveyor
Crane

Illustration

Hoisting
accessories

Hoisting
accessories

Crane

Disassembly
equipment

Application

Cutting of structures and fuel debris

Transfer of structures and fuel debris

Transfer of reactor core and reactor bottom

Built-inequipment

Crane, cableveyor, disassembly equipment

Crane (150ton), hoisting accessories

Crane (400ton), hoisting accessories

Dimensions [mm]

Φ8900 x H9500

Φ8900 x H13270

Φ12600 x H11840(Φ6000 x H7770: excluding the crane room)

Mass[ton](Container only)

Approx. 680

Approx. 680

Approx. 410

Shieldingthickness [mm]

250

250*

250*

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.554Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Method of using the isolation sheet* in combination with the work container]✓ An isolation sheet case is installed alongside the work container. The isolation sheet is enclosed in this case.
✓ The isolation sheet is installed for the purpose of controlling the spread of contaminated substances from inside the PCV and frominside the work container to the retrieval cell at the time of disengaging the work container.
✓ Following are the methods for using the isolation sheet:◆ The end of the isolation sheet is attached to the isolation sheet base at the time of placing the work container. The sheet isspread when the work container is raised.
◆ The welding and cutting of the isolation sheet is carried out using the lateral part of the shielding cart and the transportation
cart.
◆ The work container that is sealed air-tight with the isolation sheet is transferred to the additional building using thetransportation cart.
Work
container

P.N

Isolation sheet
case

P.N
Shielding
cart

Isolation
sheet baseTo the additionalbuilding

P.N

Shielding
cart
Transportation
cart

Welding andcutting
Isolation sheet

Isolation sheet

Step 1: Lifting up the work container (raising)

Step 2: Welding and cutting the isolation sheet

Transportation
cart

Step 3: Transferring the work container to the additional building

Image illustrating the transfer of a work container using the isolation sheet*Detailed studies and element tests related to the isolation sheet were carried out as part of the Isolation Technology PJ (“ Development of fuel debris retrieval method(Development of isolation technology to prevent the spread of contamination during retrieval and transportation of large structures)” PJ).
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.555Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Basic approach towards transferring structures]✓ The effectiveness of using the polar crane method as disassembly equipment was verified during the PRV head stud bolt cutting test
conducted in FY2021.
✓ The method of supporting and installing the polar crane was the issue in cutting structures using this method.
⇒ An “installation base” on which load can be actively placed inside the RPV will be used in combination. The
main proposal is to install an installation base on existing structures or on the supporting elements inside
the RPV, and thereafter to install the dismantling equipment used for the polar crane method on the
installation base.

Disassembly
equipment◆ The installation base is provided with functions other than supporting the dismantling equipment inaccordance with the characteristics of the object to be cut. The method will also have additional
functions such as using it also as a rack for storing the cut pieces, a fall prevention mechanism for thecut pieces, etc.
◆ Since the installation base and the dismantling equipment cannot be installed simultaneously (due tosize limitations of the work container), the work container needs to be replaced once after carrying in
the installation base.

[An example of installation base]

Auxiliary arm unit

Installation baseShroudUpper flange

Cutting unit
Traverse
base

Rack

Fall prevention
mechanism

Rotating
cableveyor

RPV head disassembly
equipment (Polar crane)

Jet pump

For PCV head

For jet pump
(Mounting the rack)

For the reactor bottom(With a fall prevention
mechanism）

Configuration of theequipment whiletransferring with jet pump©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.556Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Basic approach towards transferring structures]✓ It was determined that it would not be reasonable to transfer the shield plug using a work container from the perspective of theinstallation location and size.
✓ It will be removed by using a transportation cart in combination with a dedicated transfer equipment (shield plug transfer equipment )having a lifting mechanism that can rotate and traverse.
Shield plugtransfer
equipment

Liftingmechanism

Transportation
cart

Shield plug
Shield plug

Transfer
container
1. Carrying in the shield plug transfer equipment

2. Lifting up the shield plug

Transfer
container lid

Transportation
cart
3. Moving the transportation cart under the shield plug and placing
the shield plug into the container

Transportationcart

Shieldingcart
4. Closing the lid of the transfer container andtransferring with the transportation cart

To theadditionalbuilding©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.557Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Work steps (1/4)]
Step

1. Preparatory work

Contents

Passageway installation and R/Bconnection

2. Shield plug transfer
Carrying in of dedicatedequipmentWork
illustration

Outer
peripheral
外周カバー
cover

Remote operation / manual

The passageway is installed on
the gantry. In parallel, after
installing the water seal drainpipe on the surface of the oldoperation floor, the outer
Details ofwork contents peripheral cover is installed on
the cell floor surface and issecured by welding.

IssuesRemarks• Study of temporary shieldduring manual work
• Optimization of the number ofpartitions in the cell by
reducing the shielding
thickness for installation

Transportation cart

base

Closing of the well openingWork
container
Equipment for
closing
openings

Lid for transfer container

Remote operation
The dedicated equipment (shieldplug transfer equipment) is
carried in from the additionalbuilding, and is positioned on thewell. Simultaneously, thetransfer container is mounted on
the transportation cart, and ispositioned near the transfer
equipment.

Isolation sheet base installation

Lifting
Isolation sheetmechanism

Transfer
container

Shield plug
Remoteoperation /manualShield plug removal and transfer

Shield plugtransfer equipment

Passageway
連絡通路

3. Closing of the well opening

The shield plug is lifted up using
the shield plug transfer
equipment, the transportation
cart is moved under the shield
plug, and the shield plug isplaced in the container. After
closing the lid, it is transferredwith the transportation cart
(moved to the additionalbuilding).

• Study of the hoisting accessories for transferring the deformed
shield plug
• Method of controlling dust dispersion while removing the shieldplug

Remote operation

Remote operation

The isolation sheet base for
installing the work container on
the well is carried in, andinstalled on the passageway
floor surface. The transportation
cart is used for carrying it in fromthe additional building.

The work container is installedon the well, the equipment for
closing the opening inside thework container is lowered, andthe existing opening inside thewell is closed using the arm at
the extremity.

• Method of installation byremote operation• Method of closing the openings• Substantiation of equipment for
closing the openings©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.558Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Work steps (2/4)]
4. Transfer of PCV head and heat insulating material

Step
Contents

Disassembly of top portion of
PCV head
PCV head disassembly
equipmentWork
illustration

Transfer of RPV head and heatinsulating materialWork
container

Disassembly
equipment

Remoteoperation /manual

PCV head disassembly
equipment

RPV head andheat insulating
material

Transfer of RPV head

Work container

Crane

Disassembly
equipment

Hoisting
accessories

RPV head
Installationbase

Remote operation

After installing the installationbase on the PCV head, the PCV
head disassembly equipment is
set up on the installation base.
After cutting the PCV head top
portion with the PCV head
Details of
disassembly equipment, the cut
work contents
pieces of the PCV head top
portion as well as the installationbase are placed in the work
container and transferred.

Remarks

Cutting of stud bolts

Cutting tool
Installationbase
PCV head

IssuesDisassembly of bottom portionof PCV head

5. RPV head transfer

The cutting tool is suspended
from the disassembly equipment
installed inside the work
container, and the bolts
fastening the heat insulating
material are cut.
The work container is replaced,
and the heat insulating materialis placed inside the work
container and transferred.

Remote operation
After installing the installationbase on the RPV head, the PCV
head disassembly equipment is
set up on the installation base.
After cutting the PCV headbottom portion with the PCV
head disassembly equipment,
the cut pieces are placed in the
installation base. The cut piecesof the PCV head bottom portion
as well as the installation baseare placed in the work container
and transferred.

• Disassembly and removal method when the PCV head hanging metal fitting is not in a soundcondition• Remote slinging method

The cutting tool is suspended
from the disassembly equipment
installed inside the work
container, and the stud bolts arecut.

The hoisting accessory inside
the work container is suspended,and slung on to the RPV head.
The RPV head is lifted up,
placed inside the work container,
and transferred to the additionalbuilding.

• Remote slinging method

Element tests have been implemented (End of FY2021)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.559Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Work steps (3/4)]
Step

6. Dryer transfer

7. Separator transfer

8. FWS/CS pipe removal

9. Jet pump transfer

10. Upper grid plate transfer

Contents

Dryer transfer

Separator transfer

FWS/CS pipe removal

Jet pump transfer

Upper grid plate transferWork
container

Disassembly equipment

解体装置
Disassembly equipment
Pipe support
Pipe fall
prevention

Installation baseHoisting
accessories

Work
illustration
Installation base

Determined
position on
the reactor
wall

Separator

Holdingmechanism

Dryer
設置ベース
Installationbase

Remoteoperation /manual

Details ofwork contents

IssuesRemarks

Disassembly equipment

Top flange ofshroud

旋回ベース
Rotatingbase
回収ラック
Collection
rack

Disassembly
equipment

アクセス開口部
Accessopening

Clamp
クランプ
Stand for the
hoisting
解体片搬出
accessories
for
吊具台
transferring
disassembled
piecesInstallationbase

Top flange ofshroudRemote operation

Remote operation

Remote operation

Remote operation

The hoisting accessory inside
the work container is suspended,and slung on to the dryer.
The dryer is lifted up, placed
inside the work container, andtransferred to the additionalbuilding.

After installing the installationbase on the separator, thedisassembly equipment is set upon the installation base.
The cutting tool is suspended
from the disassembly equipment,
the bolts are rotated (or cut) andthe fastening is released.
After replacing the work
container, the separator is liftedup, placed inside the work
container and transferred.

After installing the installationbase on the top flange of the
shroud, the disassembly
equipment is set up on it.
The pipe is cut with the cutting
tool suspended from thedisassembly equipment while
holding the pipe with the holding
mechanism inside theinstallation base. The cut pipe
as well as the installation baseare placed in the work container
and transferred.

After installing the installationbase on the top flange of the
shroud, the disassembly
equipment is set up on it.
The cutting tool is suspended
from the disassembly equipment,
and the jet pump is cut. The cut
pieces are placed on the rack
inside the installation base.
The cut pieces are placed in thework container along with the
installation base and transferred.

After installing the installationbase on the top flange of the
shroud, the disassembly
equipment is set up on it.
The cutting tool is suspended
from the disassembly equipment,
and the portion under the middle
flange of the shroud is cut. The
top portion of the shroud isplaced inside the work cotainer
along with the upper grid plate
and transferred.

• Remote slinging method• Sound condition of the top
flange of the shroud• Remote slinging method• Sound condition of the top
flange of the shroud• Remote slinging method• Remote slinging method• Fall prevention of pipe
• Sound condition of the hanging • Sound condition of the hanging • Sound condition of the top
metal fitting
metal fitting
flange of the shroud

It is assumed that the structures
below the jet pump will behandled as fueldebris.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.560Retrieving Large Structures]① Method of cutting large structures： (a) Method of transferring unitized large structures[Work steps (4/4)]
Step
Details

11. Reactor core transfer
Filling and solidification

12. Reactor bottom transfer

Reactor core cutting and transfer

Fall prevention tool installation

Work
illustration

Ｘ

Ｘ

Frame for removing
large unitized
structures

Disassembly
equipment

Solidification
by filling

Reactor bottom disassembly
Reactor bottom
disassembly equipment
Frame for removing
large unitized
structures

Reactor bottom transfer

Work container

Reactor bottom

Reactor core
Grating cutting test
Fall prevention tool

Remoteoperation /manualRemote operation

The equipment for injecting
geopolymer is suspended from thework container, and the reactor coreand reactor bottom are filled from theupper surface of the shroud andsolidified.

• After suspending the disassembly
equipment and setting it up on the
shroud support, the portion of the
shroud under the lower flange ofthe shroud is cut using the cutting
tool at the tip.
• After changing the disassembly
equipment (cutting tool), thereactor core (filled) is cut. Aftercutting the shroud and reactor
core, shroud as well as the reactor
core are placed inside the work
container and transferred.

After making an opening in the lower
hemispherical dome of the RPV, theinstallation base is installed on the
shroud support, and is fastened to
the lower hemispherical dome using
the fall prevention tool at the tip.

After setting up the reactor bottom
disassembly equipment on the frame
for removing large unitized
structures, interfering objects andconnecting parts such as grating,heat insulating material, beams, etc.
are cut using the disassembly
equipment. After completing thework of cutting the fastening andconnecting parts, the portion of thelower hemispherical dome that is left
is cut, and the lower hemisphericaldome is separated from the RPV.

The hoisting accessory inside thework container is suspended, andslung on to the frame for removing
large unitized structures.
Along the frame for removing large
unitized structures, the reactor
bottom is placed in the work
container and transferred to theadditional building.

• Filling method in accordance withthe status of damage• Sound condition of the shroud
support• Sound condition of the shroud
support• Sound condition of the lower
hemispherical dome

• Sound condition of the shroud
support• Method of effectively cutting theinterfering objects and theconnecting parts• Remote slinging method• Sound condition of the lower
hemispherical dome

Details of work
contents

IssuesRemarks

Remote operation

Element tests have been
implemented (FY2020)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.561Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces Development policy]
Element tests on the reactor core filling andsolidification material for the reactor internal
structures below the shroud were implemented
focusing on the study on the method for cutting
structures into large pieces and the concept of
the equipment.

<Separator example> Method of separating the fastened parts assumed to
2. Removing remaining 3. T bar rotation
be damaged and deformed
1. Nut cutting portion
4. Pulling up
Disassemblyof nutthe separator

Separator

PCV head
RPV head
Heat insulating material
Dryer
Separator

Shroud head bolt

Nut

Cutting

Remaining
portion ofnut

Shroudhead bolt

Shroudhead

Pulling up the
separator

Upper shroud
Shroud head

● It may not be possible to loosen the nut
due to corrosion. Hence the nut is cut andremoved, the shaft of the T bar will berotated to remove the stopper.

equipment

Lug

Cutting
manipulator

Separator

T bar

Studies are conducted on the method of cutting structures andthe concept of the equipment.

Example of the concept ofdisassembly equipment<Example of shroud> Fuel debris retrieval by means of filling and solidification for preventing
fuel debris from falling when unitized large structures are transported is studied.
ShroudStump-shaped
fuel
CR guide tube

CRD housing

Some of thefuel in theouterperipheryremains

Fuel debris
deposited in thereactor core
ShroudCutting of entire
cross section

CRD platform
MCCI

Fuel debris
deposited at
the reactor
bottomEstimated current status

Fall prevention by injecting filler
material

Cutting of reactor internal structures(Example of cutting with wire saw)

Studies were conducted on the method of cutting structures and the concept of the equipment, and element tests
were conducted related to the rector core filling and solidification material.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.562
Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces Study conditions]• The study conditions pertaining to cutting reactor internal structures are indicated below.
ID.

Study conditions

Supplementary explanation

Remarks

1

The method of filling and solidification, and cutting will be
studied under the conditions wherein the interfering objects
from the reactor well to the separator are removed.

Work will be performed under the condition wherein the structuresother than reactor internal structures such as dryer and separator
are already removed.

2

The outflow when geopolymer is filled inside the shroud iscomparatively less. A condition wherein the geopolymer
continues to pile up is assumed.

First, as the viability, etc. of large scale filling will be verified, study
will be conducted under the conditions wherein the filler material canbe filled.
If the reactor bottom is significantly damaged and filling is difficult,the method of localized filling around the fuel debris will be selected.

3

The cutting method will be studied under the conditions wherein
filler material is filled inside the shroud without any gaps.

As cutting including the shroud as well as the filler material is
assumed to be most difficult.

4

The jet pump must be removed at the time of cutting the shroud.

As it is assumed that at the time of cutting the shroud the jet pumpwill have already been removed and the tool will have been set in
the gap between the shroud and the RPV inner surface

Since the prospects of viability of cutting the jetpump (SUS304, maximum sheet thickness11mm) is comparatively high, the level of priority
of development is evaluated to be low.

5

The shroud, etc. must not be significantly tilted.

The condition of the shroud is uncertain, but it was tentatively
installed for the study.
A configuration that would make it possible to modify the method of
fixing the tools depending on the actual site conditions will be
studied.

Results of the estimation of shroud condition
carried out during the Understanding the
Status Inside the Core PJ
Unit 1: Likely to have been damaged
Unit 2: It is assumed that there is no large scale
damageUnit 3: Likelihood of being sound and likelihoodof being damaged, both are conceivable.
Source: IRID “Subsidy Project ofDecommissioning and Contaminated
Water Management (Upgrading of theComprehensive Identification ofConditions inside Reactor)
Accomplishment Report for FY2017”©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.563Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces Study on the course of cutting]
•
•
•
•

•

In order to cut the reactor core after filling and solidification, methods of cutting the shroud structures and the filled and solidified
parts were studied.
Several structures (materials) need to be cut for removing the shroud as a unitized structure.
If bulk cutting indicated in Cutting Example 1 is considered as a pre-condition, adopting a technology that enables cutting of boththe outer circumference of the shroud and the filled and solidified part becomes a pre-condition. However, under the current
circumstances, there are no prospects of a technology for cutting both at a time.
First, Cutting Example 2: Cutting in parts is considered as a pre-condition, and a technology that can be applied to cutting the outer
periphery of shroud and the filled and solidified part is studied.
During Cutting Example 2: Cutting in parts, first the shroud is cut, thereafter, the filled and solidified part is cut with the wire saw
which has prospects of being able to cut the filled and solidified part.

① Configuration: ・ Outer periphery: Sheet thickness approx. 38mm, Material SUS・ Interior： Inner diameter approx. 4.4m, Material Filler material + CR guide tube (SUS) + Fuel debris (ceramic material)② Prospective filler material: Geopolymer
Cutting position (Cutting the fuel debris, filler material, CR guide
tube)(Image illustrating cutting of the shroud and filler material
horizontally at a time with a wire saw#, etc.)
Image illustrating steps
involved in cutting

CutterCutting location

Area that has been cut

Shift in cutting
location

Filled andsolidified part

Shift in cutting
location

Cutting the outer periphery of the shroud(The metal plate is cut first)

Cutting of remaining filler
material/ceramic material#: The wire saw is a technology that is extensively used in cutting
concrete, however, it is difficult to cut thick stainless steel plates with it.

[Cutting Example 1: Bulk cutting][Cutting Example 2: Cutting in parts]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.564Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces Selection of cutting method]
A remote operation cutting technology is desirable for the shroud considering the reaction force while cutting and emergency
collectability.
The remote operation cutting technology, its applicability to cutting the shroud, merits and demerits are consolidated in the table below.
Since stainless steel cannot be cut by means of gas cutting, and in the case of plasma arc, since there is a risk of not being able to cut
depending on the properties of the object to be cut, these two methods were excluded from the potential cutting methods.
[Merits and demerits of the various types of remote operation cutting technologies]
Cuttingtechnology

Applicability to shroud cutting

Gas cutting• Cannot cut stainless steel

Laser

Merits

Prospective cutting
technologies
Demerits--• Can cut stainless steel• Can cut thick plates depending on
the power• Can reduce the size of the cutting head
• Relatively small amount of secondary
waste(Tools for collecting secondary waste are
not required)• Dross gets generated and hinders cutting• Spread of contamination due to formationof fumes• The fuel debris inside the reactor is likely to
get damaged (Risk of criticality due tochange in shape)

Plasma arc• Can cut stainless steel (However,
may not be able to cut parts thatare adhered to fuel debris)• Can cut thick plates depending on
the power• Can reduce the size of the cutting head
• Relatively small amount of secondarywaste• Dross gets generated and hinders cutting• Spread of contamination due to formationof fumes• Needs adjustment of torch position• Cannot cut areas that do not conduct
power

AWJ

• Can cut stainless steel• Can cut thick plates• Can reduce the size of the cutting head
• Comparatively less heat input into thestructure• Relatively large amount of secondary
waste as abrasive is sprayed• The fuel debris inside the reactor is likely to
get damaged (Risk of criticality due tochange in shape)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.565Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces Selection of cutting method]
The major demerit of AWJ is the generation of secondary waste as a result of spraying abrasive.
The quantity of abrasive used per bolt in the RPV head bolt cutting element test conducted in FY2021, and the rate of collection ofabrasive in the actual equipment (assumed value) are indicated in the figure on the right.
The configuration of the equipment for collecting the secondary waste when the shroud is cut using AWJ needs to be studied.

[Quantity of abrasive used/collected per stud bolt (dry state)]
Low pressure water jet

Item
Quantity of abrasive used(per bolt)

Low pressure water
jet angle

Rate of collection

Jet flow cover

AWJ
Nozzle1370mm15.6
80% (assumed)

Quantity of abrasive used (perbolt) based on the studies on
reducing the quantity ofabrasive#

AbrasivecollectiontankWater tank

Mass[kg]

4.8#: Subsidy Project of Decommissioning and Contaminated
Water Management
Calculated while referring to results of the WJ flow rate
and abrasive supply effectiveness verification test conducted
while developing the technology for internal investigation of
RPV[RPV head bolt cutting equipment]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.566Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces Selection of cutting method]
The laser cutting technology which has relatively minor demerits based on
the study described till the previous page is being considered for cutting theouter periphery of the shroud.
The issues in the laser cutting technology are consolidated in the bottom
left table.

① When there isnothing at the rear

The processing tool needs to be equipped with functions for being able toremove dross, and being able to control the generation of fumes and cuttingof surrounding structures.
Laser nozzle[Issues in laser cutting technology]
No.

IssuesThe dross is removed
from the rear andhence does not hinder
cutting

Details

1

Dross removal

Residual dross at the location of cutting
hinders laser heat input.

2

Spread ofcontamination due
to fumes

There is a risk of spread of contamination due
to vaporization of activated material.

Damage ofsurrounding
structures(including filler
material and fueldebris)

The structures located behind the objects tobe cut may get cut due to the laser.

3

Dross

② If filling and solidificationmaterial is present at the rear
Laser nozzle

Filled andsolidified part

Dross

[Behavior of dross]

Dross remains at thecut part due to thefilling and solidificationmaterial©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofRetrieving Large Structures]

No.567① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces Selection of cutting method]
Laser + WJ cutting technology for cutting the outer periphery of the shroud is being studied.
The procedure while using this technology is indicated in the figure below. The following 3 effects are expected from WJ.
• Removal of dross by means of the WJ force• Control of generation of fumes by means of the cooling effect• Preventing cutting of surrounding structures by means of the cooling effect
If WJ is carried out continuously, it is likely to hinder laser heat input. Hence intermittent jet spray is considered as a precondition.

(c) Laser heat input
Laser nozzle

WJ
Nozzle(b) WJ, removal of molten material
WJ(c) Solidification of molten material
Solidified
moltenmaterial

To (a)

Laser beam
Molten material• The target object to be
cut is melted by meansof laser irradiation• The molten target object tobe cut is removed by means
of WJ[Laser + WJ cutting process]• The removed molten material
solidifies due to the cooling
effect of WJ(Preventing it from adhering to
the cutting location)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.568
Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Reactor internal structures (Laser + WJ Cutting)]
The issues in the laser + WJ cutting technology and the response policy are consolidated in the table below.
Element tests were conducted on Laser + WJ cutting for ① Verification of the optimum laser + WJ conditions, ② Quantitative evaluationof fume control effect, and ③ Verification of applicability to structures other than the shroud.

[Issues in laser + WJ cutting technology]
No.

Issues

Details

Response policy

1

Optimallaser + WJ
conditions

If the WJ flow rate and the jet spray duration are increased excessively, the melting of
the target object to be cut is hindered due to the cooling effect, and as a result theprocessing quantity (processing depth) reduces. Meanwhile, if the WJ flow rate andthe jet spray duration are not sufficient, molten material remains on the location of
cutting and solidifies due to which processing quantity reduces. Whether or not theWJ flow rate and the jet spray duration are sufficient depends on the quantity ofmolten material. Hence it is influenced by laser conditions such as laser power,
distance up to the object to be cut, etc. as well.

The Optimal laser + WJ
conditions will be verified
through tests.

2

Evaluationof fumecontroleffect

It is assumed that the generation of fumes can be reduced by means of the cooling
effect of WJ, but quantitative evaluation has not yet been carried out.

The changes in the quantity offumes generated due to thepresence or absence of WJ will
be verified through tests.

3

Applicabilit
y tostructuresother than
the shroud

It is assumed that various materials and shapes will need to be cut for applying thistechnology to structures other than the shroud as well.
Since the melting point or thermal conductivity changes depending on the material,
and the manner in which the WJ hits the target object changes depending on the
shape of the object, it is assumed that the optimal laser + WJ conditions will differ for
every object to be cut.

The characteristics of cutting
conditions will be consolidated
for the test pieces of various
materials and shapes assuming
the structures in the actual
equipment.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.569Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test equipment)]

2 types of cutting heads namely, horizontal cutting type and vertical cutting type, were used in the laser + WJ cutting element tests.
The cutting head consists of a laser head that irradiates laser and blows gas and a WJ head that shoots a WJ.

Horizontal cutting type cutting head
Fiber cableconnection

Laser head

WJ head
drive
shaft

[Rough dimensions(horizontal cutting)]
Location

Dimensions
[mm]

Width

136

WJ head

Depth(Excluding the WJ
head drive shaft)Laser head

Object to be cut

WJ
head

Vertical cutting type cutting head

145

HeightLaser
head(Fiber cableconnection and below)

Cutting head
feed direction
WJ
head

Laser
irradiation direction

WJ
direction

535[Rough dimensions(vertical cutting)]
Location

Dimensions
[mm]

Width

208

Depth

150

HeightObject to be cut[Illustration of horizontal cutting (Side view)](Fiber cableconnection and below)

WJ
direction

Laser
irradiation
direction

WJ
head
Laser
head

Cutting
head feed
direction[Illustration of vertical cutting(Side view)]

475©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.570Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces
Element tests (Test equipment)]
The laser head consists of ① An optical system such as a fiber cable, condenser lens, mirror, etc. and ② A gas system (explained on thenext page) for protecting the laser head from the spatter that is generated while cutting.
The laser beam formed by the laser transmitter is transmitted through the fiber cable, after it is focused through the condenser lens theirradiation direction is determined by means of the mirror, and the target object to be cut gets irradiated through the laser nozzle.
Transmission throughthe laser transmitter
Fiber cable

Lens holder
Lens holder

Protective glass ①
Condenser lens

Air hose

Shield gas
nozzleProtective glass ②

MirrorholderProtective
glass ③

Laser nozzle
Irradiation of theobject to be cut
Shield gas
nozzle[External appearance of laser head]

MirrorLaser nozzle

Mirror holder[Illustration of cutting with laser head]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.571Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces
Element tests (Test equipment)]
The WJ head is made up of the WJ nozzle unit at the center and the nozzle cover surrounding the WJ nozzle unit.
The WJ nozzle is connected to the WJ nozzle unit, and the WJ nozzle unit rotates as a result of the WJ jet spray reaction force.
The nozzle cover has an opening, and since the WJ gets sprayed at the object to be cut only when the positions of the WJ nozzle and theopening are aligned, there is intermittent WJ spraying.
The frequency of intermittent spraying is determined by the WJ pump pressure and the number of WJ nozzles. (Refer to the graph on thebottom right)
Depending on the position of
the WJ nozzle, the WJ gets
blocked by the nozzle cover.
⇒ The surplus water getsdrained from the drain port

Nozzle cover

WJ nozzle
unit

Nozzle cover

The jet sprayfrequency is almost
proportional to the
WJ pump pressure:1 WJ nozzle:2 WJ nozzles

140

Opening

Drain port

The WJ getssprayed at the object
to be cut only when
the positions of the

WJ nozzle[External appearance of WJ head]

100

When there was 1 WJ
nozzle and the pumppressure was 7MPaor less, the WJ jet
spray reaction force
was insufficient andthe WJ nozzle unit did
not rotate.

80
60
40
20
0
0

WJ nozzle and theopening are aligned

Jet spray frequency [Hz]120

Opening
angle: 30°[Illustration of the WJ head
(Traverse section)]

2

4

6

8

10

Pump pressure [MPa][Correlation between WJ pumppressure and jet spray frequency]©International Research Institute for Nuclear Decommissioning126. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.572Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Control parameters)]

The control parameters for the Laser + WJ cutting element tests are indicated in the table below.
[Control parameters for the Laser + WJ cutting element tests]
No.

Parameters

Illustration①

Power [kW]-②

Focus length[mm]

Focus length③

Stand-off [mm]Objectto be cutStand-off④

Cutting head
feeding speed[mm/s]

Details• Fixed at 7.8kW based on the equipment specification

Laser
nozzleLaser
nozzleCutting head
feeding speed

Cuttinghead• Fixed at 98mm based on the equipment specification• The size of the laser spot (diameter of the laser beamcross-section projected on the plane perpendicular to thelaser beam) at the focus length is 3mm• Distance between the laser nozzle tip and the surface ofthe object to be cut• The nearer the standoff to the focus distance, smaller isthe laser spot, greater is the quantity of heat input perunit area and greater is the amount of melting of theobject to be cut.

• The feeding speed of the cutting head while cutting• The smaller the cutting head feeding speed, greater isthe heat input per unit area, greater is the amount of
melting of the object to be cut, but greater is theprocessing time.

Object to be cut⑤

WJ Pumppressure [MPa]-• The maximum pressure is 10MPa based on thespecifications of the pump used.
• The larger the WJ pump pressure greater is the jet sprayfrequency and WJ flow rate.

⑥

Number of WJ
nozzles [-]-• 1 - 2 WJ nozzles can be installed in the WJ nozzle unit.
• Larger the number of WJ nozzles greater is the jet sprayfrequency.

⑦

Jet sprayfrequency [Hz]-• WJ jet spray frequency per second• Fluctuates depending on the WJ pump pressure andnumber of WJ
nozzles Research Institute for Nuclear Decommissioning©International6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.573Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test items)]

The test items of the element tests, their overview, objectives are consolidated in the table below.
[Laser + Pulse WJ cutting element test items (1/3)]① Stand-off conditions comparison test
Conceptual
diagram② WJ conditions comparison test

Cuttingequipment
feed direction

WJ
nozzleStand-offWJ
nozzle

Spray
angle

Cuttingequipment
feed direction
Laser nozzle

Laser nozzle

Object to be cut

Object to be cut

Overview• The cutting test is performed while changing the stand-off andfeeding speed of the cutting head, and the impact on theprocessing quantity is verified.
• Assuming that the shroud will be cut, the test piece is made of
SUS304 plate material (about t30mm).

• The cutting test is performed while changing the various conditions
concerning pulse WJ (pump pressure, jet spray frequency), andthe impact on the processing quantity is verified.
• Assuming that the shroud will be cut, the test piece is made of
SUS304 plate material (about t30mm).

Objective(Feedback forthe actual
equipment)• To verify the optimum stand-off conditions for cutting SUS304
plate material, and to reflect it in the shroud cutting conditions in
the actual equipment.
• To verify the maximum stand-off with which cutting is possible, andto reflect it in the access plan for the cutting head in the actual
equipment.

• To verify the optimum WJ conditions for cutting SUS304 platematerial, and to reflect it in the shroud cutting conditions in theactual equipment.
• To perform the cutting test in the presence and absence of WJ jet
spray, and to verify the effect of WJ on controlling generation offumes.

Measurement
items• Whether or not cutting is possible (processing depth)• Processing time

•
•
•
•

Whether or not cutting is possible (processing depth)
Processing timeAmount of fumes generated
Density of fumes©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.574Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test items)][Laser + Pulse WJ cutting element test items (2/3)]③ Materials comparison test
Conceptual
diagramWJ
nozzle④ Shape comparison test

Cuttingequipment
feed direction

Solid cylinder

Hollow cylinder

Laser nozzle

The cutting conditions are
set considering theresults of Test ① and ②.

Object to be cut

Overview• Cutting test is performed on plate material of materials other than
SUS304 that are used as reactor internal structures (carbon steel,inconel, low alloy steel, etc.), under optimal cutting conditions for SUS
plate material that were verified through tests ① and ②.

• Cutting test is performed on test pieces simulating various shapes of
the reactor internal structures (plate, solid cylinder, hollow cylinder,etc.) under optimal cutting conditions for SUS plate material that wereverified through tests ① and ② (The test piece is used in common
with the simple simulated test piece cutting test at a later stage).

Objective(Feedback forthe actual
equipment)• To verify whether or not SUS304 plate material can be cut under
optimal cutting conditions. If cutting is not possible, to identify issues(plan for changing the conditions) and to reflect them in the cutting
conditions for various structures in the actual equipment.
• To perform the cutting test in the presence and absence of WJ jet
spray, and to verify the effect of WJ on controlling generation of fumes.

• To verify whether or not SUS304 plate material can be cut under
optimal cutting conditions. If cutting is not possible, to identify issues(plan for changing the conditions) and to reflect them in the cutting
conditions for various structures in the actual equipment.

Measurement
items

•
•
•
•

• Whether or not cutting is possible (processing depth)• Processing time

Whether or not cutting is possible (processing depth)
Processing timeAmount of fumes generated (SM400B)
Density of fumes (SM400B)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.575Retrieving Large Structures][Test for assessing the impact① Method of cutting into large structures：(c) Reactor internal structureson the surrounding structures]
Refractory brick[Method of cutting reactor internal structures into large pieces
Element tests (Test items)][Laser + Pulse WJ cutting element test items (3/3)]

Laser or laser + WJ

⑤ Simple simulated test piece cutting test
Conceptual
diagram

Test piece(SUS304)

Example: Shroud
head bolt nut

Refractory
brick

Test piece

Impact on thesurface[Image illustrating the test][Cutting being performed][Test details]• A refractory brick is placed in front of the test piece• Cutting test is conducted using stand-alone laser irradiation or laser + WJ

Cutting location
Cutting location

Overview• Cutting test is performed on simple simulated test pieces simulating
the structures that are planned to be cut in the actual equipment aswell as the surrounding structures under optimal cutting conditions for
SUS plate material that were verified through tests ① and ②.

Objective(Feedback for theactual equipment)• To verify whether or not SUS304 plate material can be cut under
optimal cutting conditions. If cutting is not possible, to identify issues(plan for changing the conditions) and to reflect them in the cutting
conditions for various structures in the actual equipment.
• To check for presence of traces of surrounding structures being cut,
and if there are traces, to modify the conditions (increasing stand-off,etc,) to reduce the impact and reflect these changes in the cutting
conditions in the actual equipment.

Measurement
items[Test conditions (Common for stand-alone laser irradiation / Laser + WJ)]
• Laser power: 8kW• Cutting head feeding speed: 5mm/s• Stand-off: 60mm
• WJ pump pressure: 10MPa[Test results]• Cutting depth of the brick using stand-alone laser irradiation: 10mm
• Cutting depth of the brick using laser + WJ: 0.5mm⇒It is assumed that the impact of the cooling effect of WJ on surrounding
structures at the time of laser cutting can be mitigated.

Laser + WJ
(Cutting depth：
0.5mm)• Whether or not cutting is possible• Processing time
• Presence of traces of surrounding structures being cut

Stand-alone laser
irradiation(Cutting depth： 10mm)[Traces of the refractory brick being cut]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.576Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces
in the stand-off and WJ conditions comparison test)]

Element tests (Test results: Method of evaluating the processing depth

The test pieces used in the stand-off and WJ conditions comparison test, and the policy for measuring the processing depth are as described below.
A 40mm wide cut was made on the SUS304 test piece from right → left and the processing depth was measured at the following 3 locations.
The average of the measurement values at the 3 locations (hereinafter, “average processing depth”) will be used for assessing the processing depth.

[Information on the
SUS304 test piece]
Affixed on thetest stand witha C-clamp

SUS304 test
piece

Items

Details

Material

SUS304

Dimensions[mm]

75 x 75 x 30

Cutting
thickness [mm]30Processing depth
measurement point ③
Point at which cutting ends

Cutting width: 40mm

Cutting head feed direction

Processing depth
measurement point ②
Center

Processing depth
measurement
point ①
Point at which
cutting starts

Test stand[Outer appearance of SUS304 test piece][Cutting width]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.577Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test results: Stand-off and WJ conditions comparison test)]

Results of the stand-off and WJ conditions comparison test, and the optimal cutting conditions for the said cutting head are as described below.

[Results of the stand-off and WJ conditions comparison test]
No.

Laser
power
[kW]

Assist gas
flow rate[L/min]Stand-off[mm]

Cutting head
feeding
speed[mm/s]

Number ofWJ
nozzles [-]WJ pumppressure[MPa]

WJ jet
spray
angle
[°]

Jet
spray
frequenc
y [Hz]

Cutting
frequency [-]

Averageprocessing
depth [mm]

1

7.8

350

98

1

1

10

30

50.5

1

18.5

2

7.8

350

184

1

1

10

16

50.5

1

11.3

3

7.8

350

254

1

1

10

11

50.5

1

4.5

4

7.8

350

316

1

1

10

9

50.5

1

2.1

5

7.8

350

98 The processing 1depth

1

8

30

43.3

1

14.9

2

The ability 8to remove
molten material isgreater when
9 the WJ
pressure is higher.

30

110.5

1

9.33

30

47.4

1

15.1
9.33

6

7.8

350

7

7.8

350

increases when the cutting
98 head feeding speed
1 isincreased and cutting is
98 performed repeatedly.
1

1

8

7.8

350

98

1

2

9

30

Average processing
115.6
1
depth is maximum

9

7.8

350

98

1

1

10

30

50.5

1

15.3

10

7.8

350

98

1

2

10

30

123.5

1

9.11

7.8

350

98

5

1

10

30

50.5

5

22.2

12

7.8

350

98

10

1

10

30

50.5

10

24.0

13

7.8

350

98

10

1

8

30

50.5

10

21.3

14

7.8

350

98

10

Optimal cutting
conditions
11

The 1
WJ flow rate is lower
1
9 when there is30
50.5
10
22.0
nozzle as compared to when there are 2
nozzles, and thus the test piece does not getcooled excessively.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.578
Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test results: Materials comparison test)]

The test pieces used in the materials comparison test are as described in the table below.
Similar to the stand-off and WJ conditions comparison test, a 40mm wide cut was made in the test pieces mentioned in thetable below, and the average processing depth was compared with that of the SUS304 test piece that was cut under similar
conditions.
[Test pieces used in the materials comparison test]
Material

SM400B

SQV2A

NCF600

Geopolymer

75 x 75 x 30

227 x 700 x 30

Φ430 x 70

Φ55 (There are individual
differences in the length)

External
appearance

Dimensions[mm]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofNo.579Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test results: Materials comparison test)]

The results of cutting SM400B, SQV2A, and NCF600 test pieces using stand-alone laser irradiation / laser + WJ are indicated below.
[Difference in the status of cutting depending on the presence/absence of WJ]
Conditions

SM400B

SQV2A

NCF600

Average processing depth [mm]
0.0

10.0

20.0

30.0

SUS304

WJ Absent• The molten material adhered tothe cut part

2

WJ
Present

SQV2A• The molten material flowed
downwards on the right• The molten material was very
viscousMaterial• The molten material flowed
upwards on the right• The molten material was very
viscous

SM400B1• The molten material did notadhere to the surface• Lot of molten material
adhered to the right side of
the cut part

• The molten material did notadhere to the surface• The molten material adhered tothe surface on the right side

NCF600

3

4[Result]• It was found that the processing depth of the material that became very viscous upon melting, namely SM400B and SQV2A,
reduced.
[Considerations]• There is strong adhesive power (surface tension) between molten materials of SM400B and SQV2A, and hence it is believed that the moltenmaterial was not be removed with WJ.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.580Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test results: Materials comparison test)]

The results of cutting geopolymer test pieces using stand-alone laser irradiation / laser + WJ are indicated below.

Stand-alone laser
irradiation[Cutting conditions (Geopolymer)]
Conditions①②

Stand-off [mm]98

Cutting head feeding speed[mm/s]

5

WJ pumppressure [MPa]-Cutting frequency [-]Remarks

10

Laser + WJ

1
WJ
Absent18

Average processing depth [mm]There are glass-likeadhered particles

16
14
12
10
8
6
4

2
0

WJ
Present[Cutting status (Geopolymer)]1 laserStand-alone
irradiation

Laser +2 WJ[Average processing depth of geopolymer][Result]• It was found that the average processing depth was larger when stand-alone laser irradiation was used as compared to when laser + WJ wasused for cutting.
• When stand-alone laser irradiation was used, it was found that geopolymer melted and the molten material got dispersed due to the assist gas (There
were no sparks).
• In the case of stand-alone laser irradiation, glass-like adhering particles were seen around the cut part.
[Considerations]• In the case of laser + WJ, the cooling effect of WJ prevented the geopolymer from melting and the processing depth decreased.
→ If it is preferred that filled and solidified part are not cut as far as possible, in the case of laser + WJ cutting, the cutting depth can becontrolled to several mm.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.581Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces
Element tests (Test results： Measurement of fumes)]
The SUS304 test piece (t10mm) was cut through completely by means of stand-alone laser irradiation / laser + WJ cutting.
The total count of the fumes generated, and the particle size distribution are indicated below.
Fume measurement equipment(Electronic low pressure impactor)[Cutting conditions (SUS304 fume measurement)]②

Laser power [kW]7.8Stand-off [mm]98

Cutting head feeding speed [mm/s]

10

WJ pumppressure [MPa]-10

Remarks

WJ
AbsentWJ
Present[Results]• The total count of fumes when WJ was present declined up to
about 9% of when WJ was absent.
• The count of particles that were 0.094μm or larger in size
declined largely (about 1/10th), while the count of particles
that were smaller than 0.094μm increased slightly.
[Considerations]• The amount of fumes generated for cutting 10mm deep
declined largely if WJ was provided.
• If the amount of fumes generated is evaluated for every roundof cutting, 2.45×107 units of fumes were generated in theabsence of WJ and 1.98×107 units of fumes were generated
in the presence of WJ, and thus there was not muchdifference. However, since the number of rounds of cutting
declined largely, consequently the amount of fumes
generated declined as well.

7.00E+08
6.00E+08
5.00E+08
4.00E+08
3.00E+08
2.00E+08
1.00E+08
0.00E+00

5.95×107
Stand-alone laser irradiation
Cutting frequency requiredfor completely cutting
through: 27 times

1

Laser + WJ cutting
Cutting frequency requiredfor completely cutting
through: 3 times

Items

Details

Range within which
particle size can bemeasured [μm]0.006 to10

Number of channels[-]

14

Sampling frequency
[Hz]

10

[Total count (SUS304 fumemeasurement)]

3.00E+08： Stand-alone laser irradiation： Laser + WJ cutting

2.50E+08
2.00E+08

Count [-]①

Total count [-]Conditions

6.63×108

1.50E+08
1.00E+08
5.00E+07
0.00E+00
1
0.006

2
0.016

3
0.03

4 0.094
5
6
0.15
0.054

7
0.25

8
0.38

0.60
9

10
0.94

11
1.6

12
2.5

13
3.6

14
5.3

Particle size [μm][Particle size distribution (SUS304 fume measurement)]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.582Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test results： Measurement of fumes)]

Cutting was performed for a period of 40 seconds on SM400B test pieces (Same as the test pieces used in the materials comparison test)
using stand-alone laser irradiation / laser + WJ cutting, and the total count of the fumes generated, and the particle size distribution are
indicated below.
7.00E+08[Cutting conditions (SM400B fume measurement)]①

Laser power [kW]Total count [-]Conditions

6.00E+08②
7.8Stand-off [mm]98

Cutting head feeding speed[mm/s]

10

5.54×108

5.00E+08
4.00E+08

2.73×108

3.00E+08
2.00E+08
1.00E+08

WJ pumppressure [MPa]-10

Remarks

WJ Absent

WJ Present

0.00E+00
Stand-alone laser irradiation

Laser + WJ cutting[Total count (SM400B fume measurement)]
3.00E+08[Result]• The total count of fumes when WJ was present declined up to
about 50% of when WJ was absent.
• The fume count for particle size 0.054 to 0.094μm increased when
WJ was present (decreased otherwise)[Considerations]• Even if the cutting duration (frequency) was the same, the total
count of fumes declined when WJ was provided.
→ This is presumed to be the fume reduction effect of WJ.
• In the case of SM400B, it is believed that fumes need to bemeasured for particle size 0.006μm and smaller as well.

Large amount of fumes are
generated particularly in the caseof particle size 0.006 to 0.016μm.
→ This needs to be verified in thecase of particle size 0.006μm andsmaller as well.

2.50E+08
2.00E+08： Stand-alone laser irradiation： Laser + WJ cutting

1.50E+08
1.00E+08
5.00E+07
0.00E+00
0.006

1.6
軸ラベル
0.38 0.60 0.94
0.25
Particle size [μm][Particle size distribution (SM400B fume measurement)]
0.016 0.03 0.054 0.094 0.15

2.5

3.6

5.3

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.583Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces
Element tests (Test results: Simple simulated test piece cutting test)]
The target objects that the simulated test pieces used in the shape comparison test and the simple simulated test piece cutting test, areas described below.
Guide rod bracket
Shroud head bolt Nut
Material: SUS304
Dimensions: 200mm
x 165mmx t90mmMaterial: SUS304
Dimensions:
Φ88mm
x 281mmShroud + filled and solidified part
ShroudMaterial: SUS304
Dimensions: t38mm
Filled and solidified partMaterial: Geopolymer
Dimensions: Half of Φ55mm

Jet pump
Filled andsolidified part

CRD housing support

Riser pipe

Material: SUS304
Dimensions: Φ273mm
x 200mm
x t11mmBeam

Material: SM400B
Dimensions: 300mm
x 480mmx t75 to 115mm©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.584Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test results: Simple simulated test piece cutting test)]

The results of cutting various simulated test pieces are described below.
Items

Shroud + filled and solidified part

Guide rod bracket

Material

SUS304 + geopolymer

SUS304

Cutting
conditions

Laser power: 7.8kW Stand-off: 98mm
Head feeding speed: 1, 5mm/s (changes depending on the progress in cutting)Number of WJ nozzles: 2
WJ pump pressure: 10MPa
Spray frequency: 123.5Hz

Cutting
policyLaser power: 7.8kW Stand-off: 98mm
Head feeding speed: 10mm/s
Number of WJ nozzles: 1
WJ pump pressure: 10MPa
Spray frequency: 38.2Hz
Cut from the opposite
direction as well

Simulated filled
and solidified part

Cutting direction: 1 direction
Target processing depth: 38mm

Cutting direction: 2 directions (V shaped)
Target processing depth: 60mm
Lateral view

Status of
cutting

Cutting (through) completed
The cutting location was shifted while
maintaining a space of 3mm eachvertically in order to make it easier toremove the molten material (6 cuttinglines).

Simulated shroud

Durationof cutting

Layout drawing

Cutting completed

・ The cutting depth of the filled andsolidified part is 5mm on an average
・ Adhesion of the molten SUS304 isseen

One half of thesimulated guide rod
bracketThe molten material
collects in the cutting
groove at the intersectionof the V shape

Simulated filled andsolidified part1392[s]≒23[min](In the case of the shroud in the actual equipment: 137[h])View from the top while
cutting is being
performed

8630[s]≒144[min]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.585Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Test results: Simple simulated test piece cutting test)]

The results of cutting various simulated test pieces are described below.
Items

Shroud head bolt nut

Riser pipe

BeamMaterial

SUS304

SUS304SM400B

Cutting
conditions

Cutting
policyLaser power: 7.8kW
Stand-off: 98mm
Head feeding speed: 5mm/s
nozzles: 2
WJ pump pressure： 10MPa
Spray frequency: 123.5Hz

Number of WJ

Laser power: 7.8kW
Stand-off: 98mm
Head feeding speed: 5, 10mm/s (changed asnecessary)
Number of WJ nozzles: 1
WJ pumppressure: 10MPa
Spray frequency: 38.2Hz

Cut from the
opposite direction
as wellCutting direction: 2 direction
Target processing depth:
44mm

Lateral view

Cut from the opposite
direction as well

Cutting direction: 2 directions(V shaped)
Target processing depth: 160mm

Cutting (through) completed
Simulated shroud head boltnut (after cutting)Durationof cutting

Cutting completed

The processing depth of thesimulated hanging metal fittings
at the back is about 1mm→Minor impact on the
structures in the back

Simulated hanging metal fittings

2434[s]≒41[min]Cut from the opposite
direction as well

Cutting direction: 2 direction
Target processing depth: 75mm
Layout drawing

Status of
cutting

Laser power: 7.8kW
Stand-off: 98, 48mm (changed as necessary)
Head feeding speed: 1, 5mm/s (changed asnecessary)
Number of WJ nozzles: 2
WJ pumppressure: 10MPa
Spray frequency: 194.2Hz

Layout drawing

Cutting not completed
The cutting efficiency is
expected to improve by
investigating the optimal
cutting conditions for
SM400B

Simulated riser pipe

2856[s]≒97[min]Simulated fumes

16128[s]≒269[min](Up to processing depth of 39.9mm on an average)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.586
Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Method of cutting reactor internal structures into large pieces

Element tests (Summary)]

Element tests on laser + WJ cutting were conducted. The results obtained are listed below.
• The optimal cutting conditions for plate-shaped structures made of SUS304 material using the current cutting head wereverified.
• The difference in cutting performance in the case of various materials used in reactor internal structures such as SM400B, SQV2A,
NCF600 and in the case of SUS304 was verified.
• The effect of reduction in generation of fumes when WJ was used in the case of SUS304 and SM400B was verified.
• Cutting was performed on simple simulated test pieces simulating the material/shape of reactor internal structures, in particular,
those that are believed to be difficult to cut, and the reactor internal structures that could by and large be cut using the laser+ WJ cutting technology were verified, and in addition, improvement strategies for reducing the duration of cutting wereidentified.
• The impact on the filled and solidified part during shroud cutting was verified, and it was found that the filled and solidified partpractically does not get cut when laser + WJ cutting is used.

Also, following are the issues in further enhancing the ability to cut using the laser + WJ cutting technology and in improving the work
efficiency on the actual equipment.
• It is necessary to verify the ability to cut with respect to the domain of parameters that did not materialize during these element
tests.
(There are prospects of being able to enhance the ability to remove molten material by controlling the WJ flow rate and increasing
WJ pressure)• Although there were cases when cutting was performed by tilting the cutting head due to the correlation with the size of the cutting
head, as the target processing depth increases when cutting is performed in an oblique direction, it is necessary to reduce the sizeof the cutting head as much as possible and reduce the time required for cutting.
• Since there were cases when the molten material adhered once again, it is necessary to get creative in terms of the operation of
the cutting head such as securing a wider area for cutting, beginning to cut from the edge of the object to be cut, etc.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.587Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: FY2020 results]⚫

⚫

In FY2020, a conceptual study was conducted on the functions required of the filler material aiming for fall prevention/re-criticality
prevention.
From amongst those functions, functions No. 1 - 4 that influence the feasibility of the filling method were verified through basic tests.
No.

Required function

Details

Good fluidity at the time of filling and fillingwithout any gaps

Shape maintenance and fall prevention of the stump-shaped fuel and fueldebris should be possible by means of the filler material

2Sub-criticality guarantee of the filling method

Sub-criticality maintenance should be guaranteed at the time of solidification /transfer3

Physical strength of the filler material

4
51

Desk study

Basic test－✓✓
Criticality
evaluation✓
Addition ofabsorption
material

Filler material should be strong enough to endure processing / transfer－✓

Heat resistance of filler material

Cracks should not be formed in the filler material even if it is affected by decay
heat from the fuel debris－✓

Control of hydrogen generation by the filler
material

The filler material should be able to control generation of hydrogentransfer/transportation work✓－

<Results of Basic Test No. 1>
Geopolymer filling

CRGT without damage is simulated

Filling

CRGT

Installed at
the bottom
Simulation of collapsed CRGT
(Parameter study considering collapse angle
as 0°, 15° and 30°)

[Test conditions of the basic tests on filling]

Assumingthat there
is water atthe bottom(Depth ofwater:
Approx.
50mm)

Pail(Bottom heater temperature 60°)
CRTG was installed at the bottom of thepail and it was verified whether filling canbe accomplished without any gaps

30°
0°
15°

Angle of inclination: 30°
Cutting Angle of inclination: 0°

Cutting
Cutting

Image illustrating
the top view of thepail after filling

Angle of inclination： 15°[Results of the basic test on filling (Verifying the inside by cutting)]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.588
Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Identification of study items]⚫
⚫
⚫

The following studies were conducted in response to the issues identified in FY2020.
The characteristics of geopolymer, which is a prospective filler material, need to be ascertained in order to study the method of controlling
outflow from the through hole and for studying the method of filling taking the actual equipment into consideration.
In FY2021, the characterization test mentioned in ID.4 was conducted to evaluate the cross-sectional observation of the solidified unit.

Issues (FY2020)

Study related tomaintaining thefunction of the filled
and solidified units

Study of filling filler
material inside the
RPV anticipating theactual equipment

ID.

Implementedin (year)

StatusStudy items

Details1

Evaluation of the impact on solidification
function assuming environmental condition(temperature) inside RPV(Implemented along with ID.4)

Upon evaluating the temperature assumed inside RPV, its
impact on the solidification function was evaluated (time required
for solidification, change in strength, etc. under hightemperatures were verified).

FY2021

Explained on
the following
page2

Study related to maintaining the function
under harsh environment

The status of maintaining the required functions (impact on thechange in strength when α rays are irradiated) offered bygeopolymer under harsh environment was verified.

FY2021-2022

Explained later

3

Study of the method of filling filler material
inside the reactor

The method by which filler material ought to be injected into
RPV (how it ought to be filled at the point of injection andthereafter) was studied.

FY2022

Explained later

4

Characterization through injection test
conducted using a barrel(Implemented along with ID.1)

Characterization of geopolymer (verifying whether or not it canbe filled, its strength, etc.) was carried out through an injection
test conducted on a scale larger than the previous basic test, byusing a barrel.

FY2021

Explained on
the following
page

5

Study of the method of controlling outflow
from the through hole

The size of the opening that will enable control of outflow with anappropriate combination of temperature and additives wasstudied.

FY2022

Explained later

6

Study of the filling procedures and methods
anticipating filling at the actual site

The type of equipment required was studied considering theresults of the studies in ID.3 and ID.4.

FY2022

Explained later

7

Impact on treatment and disposal

The impact on treatment and disposal of the filled and solidified
units will be studied.

To be studied
in the future

To be studied
in the future

8

Impact when heat generating elements are
solidified

The impact on the solidified units and the method of heatdissipation (cooling), etc. when fuel debris (heat generating
element) is inside the solidified unit will be studied.

To be studied
in the future

To be studied
in the future

Evaluation of impact offilling©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.589Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Barrel injection test]⚫
⚫

The test conditions and the image illustrating the verification tests (barrel injection test) for characterization are given below.
The condition of geopolymer with different combinations when solidified under RPV internal environmental conditions (environment inwhich water is present and heat is released) was verified. In that case, silica sand was mixed with geopolymer as simulated neutron
absorbing material, etc.
ID.

Item

Conditions

Remarks

1

Types of geopolymer

3 types

The properties of geopolymer with different combinations were verified.

2

Quantity of silica sand filling

About 30%

Combined assuming neutron absorption material. The greater the quantity of filling, harder it was tobreak.

3

Barrel heating temperature

No heating, 60℃, 80℃

Assuming that heat will be released by fuel debris (the bottom part was heated).

4

Water level

100mm

・ Although details were not yet verified, it was assumed that the water level inside RPV is not as high.
・ Current sub-criticality was taken into consideration (Assumed based on the water level of subcriticality in an infinite plane.)

5Temperature measurement
position

Measured at the bottom,
175mm, 350mm, 525mm +water surface

・ About 80% (700mm) geopolymer was injected in a 200L barrel of height 900mm.
・ The internal temperature at the time of geopolymer solidification was monitored at the bottom, and at
1/4, 2/4, 3/4 the height of the barrel.
・ The temperature of water was measured by floating a thermocouple on the surface of water using afloating tube.

6

Temperature of the basic
ingredient of geopolymer

Cooled to 10℃ or less

Each basic ingredient was cooled to 10℃ or less, and was mixed at room temperature, in order tocontrol the solidification reaction during injection.

7

Geopolymer injection speed

Natural course (about 30 min)

The reduction in weight of the barrel on the supply side was measured with a weighing scale and theinjection speed was calculated from the time required and the change in weight.

Weight scale

Thermocouple

Geopolymer
Water

Mortarpump[Evaluation items]
・ Verification of the condition after filling and solidification(The solidified unit was cut into half with a wire saw and the crosssection was observed)

BarrelHeater©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.590Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Barrel injection test results]⚫ Test results (Typical example)
・ The test piece in Test No. 1 (without heating) was cut, and the cross-section was observed. It was found that several horizontal cracks
had been formed.
→ Since the intervals between the cracks matched the intervals of holes for the metal fittings used for supporting the thermocouple, it isassumed that the development of cracks originated from these holes.
It is speculated that the amount of change in volume of the outer side (vertical) and the middle of the solidified unit varied depending on⚫ Study on effectiveness of the measures (Verified by Test No. 6 and No. 7)[Test No. 6] The difference in temperature in the middle of the solidified unit and on the outer side is reduced by lowering the injection
ワイヤーソー断面写真 B
speed and improving heat release.
Note) The method of fixing the thermocouple is changed (metal fitting is excluded) in order to eliminate the anchor effect of thethermocouple support fitting.
→ It was verified that no cracks are formed. However, excluding the thermocouple support fitting could have an impact.

Overall

Enlarged view

Test No. 1 (Without heating) cross-section Comparisonof the cracks and the thermocouple support fittings

Test No. 6 (1 round of injection) cross-section
断面 1

断面割れ上部©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.591Retrieving Large Structures]
ワイヤーソー断面写真 A① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Barrel injection test results]⚫ [Test No. 7] Heat release is improved further by splitting injection into 3 rounds at the same injection speed as No. 6.
コア写真 2 本目

Test No. 7 (3 rounds ofinjection)
cut surface断面割れ上部
断面
1

コア全体

上部コア

中段コア

下部コア

Test No. 7 (3rounds of injection) results of core boring
断面割れ下部・ It was verified that a boundary line is formed for every injection. The cut pieces were bound when the cross-section wasobserved but got separated at the boundary line due to the impact at the time of core boring. → The possibility of lack ofadhesion was verified.
コア全体長

⚫

上部断面

The FY2022 implementation details were studied based on the cause of formation of cracks and the response measures.
Cause

Countermeasures

The difference in temperature in
the middle of the solidified unit
and on the outside was large

Improving heat release

It was verified in FY2021
that the measures were
中段上部断面
effective.

Major shrinkage on curing

Reducing GP ratio(= Increasing the fine aggregatessuch as silica sand, etc.)

Implemented in FY2022 as fundamental measures forcontrolling generation of defects (Study item ID. 4-2)#

Implemented even in FY2022 since lack of
中段下部断面adhesion was
an issue (Study item ID. 4-3)#

下部断面

Large thermal expansion

Using low heat release GP
断面 2

The necessity of implementation will be determined based on
the FY2022 results

断面割れ上部

断面割れ下部# Described on
the next page

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.592Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures: Added in responseto the results of ID. 4[Study on filler material: FY2021 results and FY2022 implementation items]
Issues (FY2020)

Study related tomaintaining thefunction of the filled
and solidified units

Study of filling filler
material inside the
RPV anticipating theactual equipment

Implementedin (year)

StatusUpon evaluating the temperature assumed inside RPV, its
impact on the solidification function was evaluated (time required
for solidification, change in strength, etc. under hightemperatures was verified).

FY2021

Implemented

Study related to maintaining the function
under harsh environment

The status of maintaining the required functions (impact on
the change in strength when α rays are irradiated) offeredby geopolymer under harsh environment was verified.

FY2021-2022

Explained on
the following
pages.

3

Study of the method of filling filler
material inside the reactor

The method by which filler material ought to be injected
into RPV (how it ought to be filled at the point of injection
and thereafter) was studied.

FY2022

Explained on
the following
pages.

4

Characterization through injection test
conducted using a barrel(Implemented along with ID.1)

Characterization of geopolymer (verifying whether or not it canbe filled, its strength, etc.) was carried out through an injection
test conducted on a scale larger than the previous basic test, byusing a barrel.

FY2021

Implemented

4-2

Measures by increasing the amount offilling of silica sand(Implemented along with ID.1)

A test was conducted using a barrel wherein the amount ofshrinkage of the entire solidified unit was reduced byincreasing fine aggregates, as a crack countermeasure.

FY2022

Explained on
the following
pages.

4-3

Extension work

The impact of extension work on the strength of thegeopolymer was verified as a countermeasure for lack ofadhesion. Whether there is an extension interval that does
not reduce the strength was verified.

FY2022

Explained on
the following
pages.

5

Study of the method of controlling
outflow from the through hole

The size of the opening that will enable control of outflow
with an appropriate combination of temperature andadditives was studied.

FY2022

Explained on
the following
pages.

6

Study of the filling procedures andmethods anticipating filling at the actualsite

The type of equipment required was studied considering
the results of the studies in ID.3 and ID.4.

FY2022

Explained on
the following
pages.

7

Impact on treatment and disposal

The impact on treatment and disposal of the filled and solidified
units will be studied.

To be studied
in the future

To be studied
in the future

8

Impact when heat generating elements are
solidified

The impact on the solidified units and the method of heatdissipation (cooling), etc. when fuel debris (heat generating
element) is inside the solidified unit will be studied.

To be studied
in the future

To be studied
in the future

ID.

Study items

Details1

Evaluation of the impact on solidification
function assuming environmental condition(temperature) inside RPV

2

Evaluation of impact offilling©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.593
Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Measures by increasing the amount of filling of silica sand]ID.
4-2

Details

Measures by increasing theamount of filling of silica sandA test was conducted using a barrel wherein the amount of shrinkage of the entire
solidified unit was reduced by increasing fine aggregates, as a crack
countermeasure.

Test item

Table flow
test

Stressmeasurement
test

Objective

Test results

To study the combination
with silicon sand such thatthe table flow that can bepumped up using theexisting mortar pump is
15cm or more.

・Amongst the combinations that werestudied, the table flow exceeded 15 cm when
the addition was 50wt% and was under
15cm with 60wt%. Hence 50wt% silica sandfilling was selected.
・And amongst those combinations, silica
sand combination of No. 4 : No. 8 = 4 : 1 wasselected as the test condition. (Particle size
No. 4: 0.21 to 1.18mm, No. 8: 0.05 to
0.15mm)In order to verify whether
increasing the amount ofsilica sand filling is effective
as a crack countermeasure,the impact of thermal
expansion was verified withthe combination selected in
the table flow test.

・It was verified that the change in volume
decreases when the amount of silica sandfilling is increased, and it was verified that
adding fine aggregates is effective as a crack
countermeasure.
→ It was verified that 50% silica sand filling
was an effective combination this time.

Flow value [mm]Table flow test(#) and strain measurement test were conducted to verify the combination with silica sand used in the test using abarrel and its effectiveness. (#) Test that shows the indicator of softness of mortar(No. 8 + No. 9 = 1:0.75)(No. 4 + No. 8 = 8:1)
(No. 4 + No. 8 = 4:1)

Quantity of silica sand filling [wt%]Correlation between the quantity of silica sandfilling and the flow value

Silica sand 0%
Silica sand 25%
Silica sand 50%

Actual stress x 10-6[-]⚫

Study items

Curing period

Changein stress against
thenumberdays elapsed.
©International
Research
Institute
forofNuclear
Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.594Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material： Test using a 200L barrel]⚫ Conditions for the test using a 200L barrel：
FY2021

FY20227 (3 rounds of injection)

This test using a 200L
barrel

1, 2, 3

Types of geopolymer

SIAL®
(Combination assumingthat it is used underwater and that it
solidifies in a short time)

Metakaolin + Na series

SIAL®
(Combination assuming that there is almost no water
but that the humidity in the environment is close to100%)

Silica sand combination

Only No. 8

Only No. 9

No. 4 : No. 8＝ 4:1

Quantity of silica sandfilling(wt%)

1630

20/40/40

50

Flow value (cm)#1

21

20

Not measured

17

Thermocouple

Present (in the middle ofthe barrel, with support)

Present (in the middle ofthe barrel, without
support)#2

AbsentWater level (mm)100

AbsentHeating with a heater

No heating/ 60℃/ 80℃

No heating

Injection method

6Preliminary test using
200L barrel

Test No.

AbsentPresent (in the middle ofthe barrel, without
support)#2
AbsentPump injection

No heating

40℃ (lateral side +bottom)#3 approx. 2
weeks

AbsentRepairs

Injection speed (kg/min)

29.7/11.8/15.2

8.5

9.9 (Reference value)－

5

Weight (kg)282/276/259(Before solidification)

331(Before solidification)

326.4(Before solidification)

314.6(After solidification)

244.4(Before solidification)(#1) Value measured during the test conducted in the laboratory(#2) Since cracks were formed in the long plate-shaped support, it was changed to a thin elongated metal shaped support(#3) Configured while referring to the current RPV bottom temperature (33.9℃/Unit 2), and heater added to the lateral side in order to heat evenly.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.595Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material： Test using a 200L barrel]⚫ Test equipment, etc.:
Screw feeder

Metakaolin
Blending equipment

Blending equipment(Pouring Metakaolin)

Blendedgeopolymer

Cutting equipment (Wire saw)

Thermocouple

Injection started

Injection completed (50 minutes
after start of injection)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.596Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material： Results of test using a 200L barrel]⚫ Test results:

Near the surface

Near the surface

Overall

Overall

Near the bottom
Preliminary test using 200L barrel (Without injection)

Near the bottom

This test using a 200L barrel (Repairs)

・As a result of observing the cross-section, it was found that there are no cracks on the inside, and silica sand is evenly distributed.
→ It was verified that the response measure of increasing the amount of filling of silica sand is effective.
・ On comparing the preliminary test using 200L barrel and this test using 200L barrel, it was found that there was a difference in the size
(number) of holes.
→ It is assumed that since air got trapped while performing the filling due to the repairs, the air remained as is in this test.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.597Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Extension work]ID.
4-3

Study items

Details

Extension work

The impact of extension work on the strength of the geopolymer was verified as acountermeasure for lack of adhesion. Whether there is an extension interval that
does not reduce the strength was verified.

⚫ Joint placement test
<Test details> Compression test and tensile test of the test piece with joint placement were conducted, and its cross-section wasobserved. The results were compared with those of a test piece without any joint placement.
<Test conditions> The intervals between the joints were changed. The geopolymer used was from Company A (Same blend as thetest using a 200L barrel)<Test procedures>① Filling up to half of the formwork(Used framework (Φ50 x 100))③ Conducting compression test / direct
tensile test
/ cross-sectional observation② Filling up the rest of the formwork

Joint placement interval
0.5/1/2[h]Atmospheric curing(28 days)⚫ Direct tensile test method
Both end surfaces of the test piece were polished and smoothened, and the tool was fixedwith epoxy resin adhesive. After letting it stand for 24 hours, the tensile test was conducted.

Picture of the direct tensile test

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.598Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Joint placement test results]⚫ Results of the compression test / direct tensile test
Compression
test

Joint placement
intervals [h]Compressive
strength
[MPa]

1

2

3

1

2

3

1

2

3

72.3

84.2

69.7

98.9

77.2

96.7

66.6

107.2

109.2

98.2

Average
Tensilestrength[MPa]

Tensile test

Individual

0 (No joint placement, forcomparison)1
2
3

Individual

92.1

80.2

1

84.3

2

80.2

104.9

1

2

3

1

2

3

1

2

3

1

2

3

6.4

5.2

5.8

6.3

5.1

5.1

5.8

6.3

6.6

6.7

6.7

4.9

Average

External appearanceof test piece after the test

76.1

0.5

5.8

5.5

6.2

6.1

No. 1

No. 2

No. 1

No. 2

No. 3

No. 3

No. 3

No. 3

(Typical examples): Breaks at the joint

・ It was verified that there is some variation in the compressive strength and tensile strength up to a joint placement interval of 2 hours, but thestrength does not decrease.
・ As a result of observing the external appearance of the tensile test, it was found that the test piece breaks not just at the interface of the joint(center) but at other parts as well, and was thus verified that the joint interface was not different than other sites in terms of its strength.
→ It was verified that joints can be placed up to 2 hours which is within the timeframe of the test.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.599Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Joint placement test results]⚫ Results of cross-sectional observation
・ The area near the cut part and the joint interface of the test pieces that did not undergo the compression and tensile test
were observed.
→ In the case of all test pieces, there were no interfaces and no uneven distribution of silica sand.
→ It is believed that the first and second geopolymer bodies blended until the 2 hour joint placement interval which is within
th scope of the implemented test.
・ In the future, it is necessary to acquire data when the extension interval is 2 hours or more assuming the actual equipment
is being used.
Joint placement interval [h]0 (No joint
placement)

0.5

1

2

Joint interface©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.600Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material： Study related to maintaining functions under harsh environment (When α rays are irradiated)]ID.
2

Study items

Details

Study related to maintaining
the function under harshenvironment

The status of maintaining the required functions (impact on the change in strength
when α rays are irradiated) offered by geopolymer under harsh environment areverified.

⚫ Observation of external appearance and SEM observation, measurement of Vickers hardness (geopolymer from Company C)<Test details> Fuel pellets (radiation flux approx. 4.5 x 109 α/m2∙s) to which broken cladding is adhered, which are collected from fuelelements with an average burn-up of approx. 57 GWd/t are embedded in geopolymer, and are observed and measured after apredetermined time has passed.
<Test condition> Measured 4 times, retrieved from the hot lab at the start of the test and after 30 days, 64 days and 427 days havepassed since the start of the test.
Vickers hardness measurement location: Region of contact of the test piece for hardness measurement to the fuel, middle
region, top region, weight: 10g (98mN)<Test piece> Age 21 days, solid state, without additives (blank conditions)<Test results: External appearance observation and SEM observation>
It was verified in the composition observation performed during external appearance observation and SEM observation that there are no
major changes.
Top region
Geopolymer<Test results: Vickers hardness measurement>
・ The hardness was greater in the case of locations that were exposed to α radiationas compared to locations that were not exposed.
・ Since hardness tends to increase due to α radiation, measuring the strength in the
future is considered.

Middle region

Test piece for observing the structure
SUS storage container

Region in contact
with fuel
Fuel pellets = α ray source©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.601Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of controlling outflow from the through hole]ID.
5Study items

Details

Study of the method ofcontrolling outflow from thethrough hole

The size of the opening that will enable control of outflow with an appropriate
combination of temperature and additives is studied.

⚫ Opening sealability verification test (Geopolymer from Company C)<Test details> The prepared geopolymer is poured into the transparent polypropylene 40 x 76 x 236mm container that is 2mm thick andat the bottom surface of which 3 holes of size 5mm have been made, and the vertical sealability at the point in the hole where it hasreached is verified.
<Test conditions> The following 3 types of geopolymer are used.
No.

State of GP

Density [g/ml]

Viscosity [Pa・s]

Flow value [cm]

1

Blank

1.79

2.58

21.3

---

2

50% silica sand added

1.98

5.75

15.9

Silica sand is added to prevent shrinkage that increases
viscosity

3

Cured for 6 hours after
preparation

1.79

5.48

Not measured#

Remarks

Cured for increasing viscosity# Reference value after 7 hours of curing: 13.7 [cm]GP injection point

Distance from the point of injection of geopolymer to the opening
Hole

Distance from the point of injection [cm]Overview diagram of the openings at the bottom of the container(Length of the side excludes the thickness of the container)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.602Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Opening sealability test results]
・ It was verified that all 3 types of geopolymers dripped continuously right after reaching the opening, the quantity that was
falling decreased gradually and the opening got sealed.
No.1 (Blank)

No.2 (50% silica sand added)

No.3 (Cured for 6 hours)

Density [g/ml]

1.79

1.98

1.79

Viscosity [Pa・s]

2.58

5.75

5.48

Flow value[cm]

21.3

15.9

Not measured

Quantity ofgeopolymer falling

MediumLargestSmallest

Speed of falling

FastestSlowestMediumTime until the opening
was sealed

6 minutes

11 minutes or more

5.5 minutes

Right after reaching
opening ③

After 5 minutes

・ As a result of comparing No. 1 and No. 3, it was found that under similar density conditions as viscosity increased the sealability increased.
・ As a result of comparing No. 2 and No. 3, it was found that under close viscosity conditions greater the density lower was the sealability.
→ It is believed that using a geopolymer that is characterized by greater viscosity and lower density would be effective for vertical sealing of the
opening.
・ In the case of the combination with 50% silica sand as well, which is used in ID.4-2, 3, there were prospects of being able to seal Φ5mm
openings.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.603Retrieving Large Structures]〇： Issues are present① Method of cutting into large structures ：(c) Reactor internal structures△: Countermeasures are being implemented
×： No issues[Study on filler material: Consolidation of requirements]
No.

Requirements

Evaluation items

Numerical
target(Tentative)

Remarks andcountermeasure policy

Whetherthere
areproblems

1

It should be possible to secure sufficient time from completion ofTime, temperature
blending to completion of pouring under the prescribed temperature

2

Feeding with a pump should be possible

Flow values

3

The filler material should be able to penetrate the gaps in the fueldebris and structures

Viscosity

4

It should be possible to maintain sub-criticality

Quantity of neutron absorption
material, homogeneity

Will be set
in the future

It has been verified that the neutron absorption material (B or Gd) canbe mixed with geopolymer.

△

5

Strength should not decline after extension work

Tensile strength

Will be set
in the future

It has been verified that the strength does not decline up to a 2 hour
extension work interval. In the future, the extension work interval thatwould be effective in the actual equipment needs to be verified.

△6

It should be able to seal the openings

Viscosity, density

Will be set
in the future

It has been verified that openings with a 5mm diameter can be sealed.

△7

It should solidify and be able to withstand its own weight

Compressive strength, tensile
strength

Will be set
in the future8

Its strength should not be lower than the prescribed strength under Compressive strength and tensile
radiation environment
strength after exposure to radiation

Will be set
in the future

Requirements in terms of strength will be studied based on the filling
method (complete filling, partial filling) depending on the status inside
the reactor.

〇

9

Its strength should not be lower than the prescribed strength under Compressive strength and tensile
water injection environment
strength under waterWill be set
in the future10

It should be able to withstand the decay heat from fuel debris(Cracks, etc. should not form)

Upper temperature limit

300°C

It has been verified in a laboratory that it can withstand temperature up
to an upper temperature limit of 300℃.

△

11

It should be possible to control the generation of hydrogen as aresult of radiolysis of water

Amount of hydrogen generated (Gvalue)

Will be set
in the future

It has been verified that the amount of hydrogen generated in the caseof the test piece in which the geopolymer is mixed with Pd powder isbelow the lower limit of detection.

△

Hardness

Will be set
in the future

There are proven track records of being able to cut using concrete
cutter, wire saw and laser cutting.

△12

It should be possible to cut it.

6 hours at 10℃ Pouring equipment that can maintain the prescribed temperature willor lower
be studied.
Temporarily set using the existing pump. In the future, feeding will be
15cm or more set depending on the pumping capability when using the actual
equipment.
It has been verified in FY2020 that the feeding material can penetrate
CRD.GT gaps when the viscosity is 10Pa・S and the temperature is
60℃.
10Pa・S
Since there is the risk of cracks if there are inclusions, verification testneeds to be conducted on the geopolymer combination prepared this
time.

〇
〇

△

Note: Consolidation of requirements related to long-term storage (radioactive nuclide confinement function), waste treatment and disposal are issues that will be studied in the futureand hence are not included in this table.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.604Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of filling filler material inside the reactor]
ID.

Study items

Details3

Study of the method of filling filler
material inside the reactor

The method by which filler material ought to be injected into RPV (how it ought tobe filled at the point of injection and thereafter) is studied.

6

Study of the filling procedures
and methods anticipating filling in
the actual equipment

The type of equipment required is studied considering the results of the studies in
ID.3 and ID.4.

⚫ The methods of filling filler material into the reactor are largely classified into complete filling and partial filling.
⚫ The filling methods are consolidated in accordance with the status of damage.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.605Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of filling filler material inside the reactor]
A. Damage progression

Small scale

Conceptual diagram

Some of thefuel remains in
the reactor core

Major part of
supportstructures
have
retained theirform

Fuel debris ispresent at thereactor bottom
Little has flown
to the pedestal

Few
openings arepresent in
the lower
hemispherica
l domeFilling andsolidification

Response•

B. Damage progression

Medium scale

Major part of
the fuel has
flown to thelowerhemispherical
dome

Many of the
supportstructures
have melted
and have
gottendamagedFuel debris ispresent at thereactor bottom
A lot has flown
to thepedestalMany
openings arepresent in
the lower
hemispherica
l domeC. Damage progression

Large scale

Major part of
supportstructures
have melted
and flown out

Major part of
the fuel has
flown on to thepedestal

Structures in
the lower
hemispherica
l dome havemelted andfallen on to
the pedestal

Localized fillingand solidification

MeritsDemerits

・ Localized filling and solidification of the remaining
fuel debris
・ Reducing the scope to the part where fuel debris
remains, cutting into large pieces and transferring

・ Filling and solidification not required
・ Cutting into portions as large as can be transferred・ Detailed positioning of the scope of filling is not
required・―・ Large quantity of geopolymer required

・ Dikes need to be set up so that the geopolymer does
not flow out from where it has been filled•

Filling and solidification of fuel debris inside thereactor core and at the reactor bottom
Cutting and transferring as large structures

Small quantity of geopolymer required―⚫ The filling methods for the above-mentioned status of damage are studied in this document.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.606Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of filling filler material inside the reactor]⚫ The following 2 methods for filling geopolymer were studied.
Batch processing

Concept

Continuous pouring

The material is mixed inside the reactor, and by
reducing the distance up to the filling location, fillingis carried out while retaining fluidity

The material is mixed on the gantry and is fed into the reactor with a hose thus carrying out
continuous pouring

Hose reel
Mixingequipment

Hopper
Cooling container

Intermediate storage tank
(Cooling container)

RPV

StirrerUpper grid
plate

Hose
Work
container

ShroudIllustration

Connecting
pipes
Hose

Core support
plate

Auxiliaryrobot

CR guide tube

Hose
Commonequipment(Hoisting, rotating)
Auxiliary robot

Lowerhemispher
ical dome
Geopolymer
Geopolymer©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.607Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of filling filler material inside the reactor]⚫ Overview of the batch processing method (1/2)

Common equipment(Hoisting, rotating)Upper grid
plate

Work
container

Geopolymer injection
equipment(Geopolymer stirring, pouring)

Stumpshaped fuelCore support
plate
Auxiliary
robot
Sand bags

Net

CR guidetube<Pre-conditions>
After removing the interfering objects with thehelp of disassembly equipment and auxiliary
robot, the size of the opening in the reactor
bottom lower hemispherical dome is reduced byinstalling a net and sand bags, thus making it
possible to seal the opening with geopolymer.
At the time of reactor core meltdown, sand bags
are piled up to prevent geopolymer from flowing
out from gaps in the shroud leg (explained on thefollowing page).
If it is difficult to install a net due to the conditionof the lower hemispherical dome, fallen objects
are collected using a fall prevention sheet
installed from the reactor bottom.
⚫ The geopolymer injection equipment isloaded in the work container inside theadditional building, and is transferred inside
the RPV.
⚫ The equipment for injecting geopolymer issuspended from the work container, and isinstalled on the upper surface of the shroud.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.608Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of filling filler material inside the reactor]⚫ Overview of the batch processing method (2/2)
Hopper

Cooling
container

StirrerUpper gridplate
Stumpshaped fuel
Hose

Auxiliary
robotCore support
plate⚫ The material inside the hopper is poured into thestirrer and geopolymer is prepared.
⚫ The prepared geopolymer is injected into the reactor
bottom by means of a hose. In doing so, the point of
injection is adjusted with the auxiliary robot.
⚫ If the reactor bottom cannot be accessed because ofremnant structures in the reactor core, the bottom isaccessed from the outer periphery of the shroud leg,
the reactor bottom is solidified and then the reactor
core is filled.
⚫ After completing the work of injecting geopolymer
from inside the stirrer, the hose is transferred to theadditional building for refilling the next batch ofmaterial.
⚫ Hereafter the process is repeated.

CR guide tube

Sand bags

Net

Geopolymer

During reactor core meltdown

When there are remains at the reactor core
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.609Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of filling filler material inside the reactor]⚫ Overview of continuous pouring method<Pre-conditions>
Similar to the batch processing method⚫ A work container on which a hose reel is mounted isinstalled on the top surface of the shroud.
⚫ The hose from the hose reel is connected to theconnecting pipes from the intermediate storage tankinstalled on the gantry.

Mixing equipment
Intermediate storage tank
(Cooling container)

HoseWork container
Connection pipes(insulation material)

Commonequipment(Hoisting, rotating)⚫ The geopolymer is prepared using the mixing
equipment and is pumped to the intermediatestorage tank.
⚫ The hose from the hose reel is connected to theconnecting pipes from the intermediate storage tankinstalled on the gantry.
⚫ Once the tip of the hose is positioned on theinjection point at the reactor bottom, the geopolymer
is pumped from the intermediate storage tank.

Separate equipment(Hose reel)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.610Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Study of the method of filling filler material inside the reactor]⚫ Comparison of the filling methods

MeritsDemerits

Batch processing

Continuous pouring

・Fluidity is retained easily as the injection point isnear the mixing location.
・Maintenance is easy as the equipment is changed
every time・Supply of material is easy as the material is mixed
on the gantry.
・The amount of work can be reduced as theequipment does not have to be changed.

・Since only a small quantity can be injected at a time,
many extensions are required.
・Since the work of changing the equipment (including
refilling material) takes time, the work until completionof filling takes time.

・A longer hose is required due to which it is difficult topump or cool (heat insulation) the geopolymer.
・As the hose is long, the geopolymer is likely to getsolidified inside the hose while it is being pumped.
Also, in that case, it is difficult to handle the hose andemergency retrieval of the hose becomes challenging.
・Since mixing and intermediate storage is carried out
on the gantry, the size of the gantry may have to be
increased.

⚫ Conclusion
Since hose treatment is required and a temperature of 10℃ or lower (to ensure fluidity) must be retained, the batchprocessing method that is easy to manage will be studied as the potential method.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.611
Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Summary]⚫ The characterization of geopolymer that is being considered as a filler material was carried out through injection
tests using a barrel.
⚫ Solidified units without cracks can be prepared using a barrel at the assumed temperature inside the RPV (40℃).
The effectiveness of increasing the quantity of silica sand filling (50% addition) as a crack countermeasure wasverified.
In the future, the effectiveness of crack countermeasures when there are inclusions remaining, needs to beverified.
⚫ As a result of the extension work test, it was verified that joints can be placed up to 2 hours.
Blending of the first and second geopolymer body was verified. Even in terms of strength, there was no differencewith other sites.
In the future, the extent to which the joint placement time can be extended needs to be verified.
⚫ It was verified through impact verification tests that hardness tends to increase as a result of radiation exposure.
In the future, strength needs to be verified as well.
⚫ The specifications required of the filler material were consolidated, and issues in actual equipment application andin scaling up were identified.

⚫ The method of filling filler material in the actual equipment was studied, and considering the batch processing
method as a potential method from the perspective of retaining fluidity of the geopolymer, conceptual studies
were conducted including on the method of controlling outflow from the through holes.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.612Retrieving Large Structures]① Method of cutting into large structures ：(c) Reactor internal structures[Study on filler material: Summary]IssuesID.

Study items

Study results

IssuesStudy related tomaintaining thefunction of thefilled andsolidified units

1

Evaluation of the impact onsolidification function assuming
environmental condition(temperature) inside RPV

It was verified that solidified units without cracks can be prepared using abarrel at 40℃ which was the assumed temperature inside the RPV.

It is necessary to improve data on the strength and temperature at theextension interval (2 hours or more) assuming the actual equipment is being
used.

2

Study related to maintaining thefunction under harsh environment

It was verified that there is no major change in the external appearance andthe composition when exposed to α radiation, and that hardness tends toincrease.

The impact of α radiation during the period from completion of mixing tocompletion of solidification of the geopolymer needs to be verified.

3

Study of the method of filling filler
material inside the reactor

The batch processing method and continuous pouring method were studied
as methods of filling filler material in the RPV. The batch processing method
will be studied as a potential method from the perspective of retaining fluidityof the geopolymer.

The filling equipment needs to be substantiated for its use in the actual
equipment and issues in the filling method need to be identified byconducting element tests. Also, studies need to be conducted on methods
for improving throughput.

4

Characterization through injection
test conducted using a barrel(Implemented along with ID.1)

It was verified by conducting the injection test using a barrel that thegeopolymer can be filled and that it meets the requirements as filler material.

4-2

Measures by increasing the amountof filling of silica sand(Implemented along with ID.1)

It was verified that solidified units without cracks can be prepared using abarrel by increasing fine aggregates as a crack countermeasure. Also, it wasverified by conducting a stress measurement test that increasing fineaggregates is effective in controlling thermal expansion.

4-3

Extension work

It was verified that joints can be placed up to 2 hours which is within the timeframe of the test. At that time, blending of the first and second geopolymer
bodies was verified based on cross-sectional observation, and it was verified
that the joint interface was not different than other sites in terms of its strength.

Refer to ID.1

5

Study of the method of controlling
outflow from the through hole

It was verified that an opening of Φ5mm can be sealed by injecting ageopolymer composition consisting of 50% silica sand filling.

Issues in the methods (combined with net, sand bags, etc.) of controlling
outflow from the through holes assumed to be present in the actual
equipment need to be identified by conducting element tests.

6

Study of the filling procedures andmethods anticipating filling in theactual equipment

Conceptual studies were conducted on equipment required for the batchprocessing method.

Refer to ID.3

7

Impact on treatment and disposal

The impact on treatment and disposal of the filled and solidified units will be
studied.
(To be studied in the future)

In addition to the track record of application to high-level radioactive waste(stored in barrels), it is being said that the cesium leaching control effect isbeing verified as part of the JAEA wisdom projects. Treatment and disposal
methods need to be studied based on these data on geopolymer properties.

8

Impact when heat generating
elements are solidified

The impact on the solidified units and the method of heat dissipation (cooling),
etc. when fuel debris (heat generating element) is inside the solidified unit will
be studied. (To be studied in the future)

Along with acquiring fundamental data from when the fuel debris isembedded in the heat generating elements, filling methods to be used in theactual equipment (heat dissipation, cooling) need to be studied.

Study of filling
filler material
inside the RPV
anticipating theactual equipment

Evaluation of
impact of filling

The thermal expansion effect measurement data needs to be improved
assuming the use of actual equipment. Also, the effect of crack
countermeasures while the geopolymer is inside the structures assuming its
use in the actual equipment needs to be verified.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.613Retrieving Large Structures]① Method of cutting large structures: Planned: Planned (after revision)*: Actual◼ Development Process
FY2021

FY2022

Study items
4

5

6

7

8

9

10

11

12

1

2

3

Interim Report▼

Major milestones

45Interim Report
▼

6

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final
report
▼1. Conceptual study

Cutting of reactor internal structures
2. Element test plan

3. Test preparation /Test manufacturing of test
equipment(Moved up from the original plan of
October 2022 onwards)

4-1. Element tests(Cutting of RPV head bolt)

4-2. Element tests(Cutting of reactor internal
structures)

5. Summary

Remarks

・ 4-1. Element tests were completed in March 2022.
・ 4-2. Element tests were completed in January 2023.

* The plan was revised to reflect the study progress status and the results of element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.614Retrieving Large Structures]① Method of cutting into large pieces: Summary➢ Pre-conditions pertaining to the method of transferring unitized large structures were consolidated,and overall steps were created.
➢ The methods for cutting the stud bolts of the RPV head from among the structures inside the reactor
well were studied in FY2021, as a part of cutting “structures other than reactor internal structures”,
test pieces (RPV head, bolts) simulated to the actual equipment scale were manufactured, andelement tests on cutting the bolts with AWJ were conducted. The feasibility of the method of cutting
the RPV head bolts was verified, and issues were consolidated. (Reported under “Accomplishment
Report for FY2021*”)➢ In order to cut the reactor core after filling and solidification, methods of cutting the shroud
structures and the filler material were studied, as a part of cutting “reactor internal structures”. The
method of cutting the outer periphery of the shroud was developed on a priority basis in order toproceed with cutting the inside (filled and solidified part) in parts after cutting the outer periphery of
the shroud.
➢ The laser + pulse WJ cutting was selected as the method for cutting the outer periphery of the
shroud, element test plan was drafted and the tests were conducted. Based on the results of theelement tests, the feasibility of application of the method to cutting the outer periphery of the shroud
was verified, and issues were identified and consolidated in preparation for designing the actual
equipment.
➢ In addition to the characterization of geopolymer that is being considered as a filler material, carriedout through injection tests using a barrel, tests were conducted to verify the impact of exposure toradiation and issues were identified and consolidated in anticipation of application in actual
equipment and scaling up. Also, work steps involved in filling and solidification were organized.

*Accomplishment Report for FY2021: https://irid.or.jp/wp-content/uploads/2022/08/2022007_deburitoridashi.pdf©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofRetrieving Large Structures]

No.615② Large transfer containers
With respect to retrieving fuel debris and reactor internal structures, in order to enhance thethroughput using the top access method, the method of transferring unitized large structures is being
studied as part of the development being undertaken since FY2019. To make this possible, thestructures need to be separated from the reactor and these large structures need to be transferred.
Large transfer containers used for transferring the large structures, which will have a contamination
spread prevention function and a shielding function for the high radiation items stored in them, need
to be developed.
From FY2020, the preconditions and the required development items for the large transfer containers
are being studied and consolidated, the site applicability of the large transfer containers is being
evaluated through development of the air-tight and shielding structure for the lid portion of the largetransfer containers, conceptual studies on the transfer systems and element tests related to theviability of the air-tight structure of the lid portion, and the issues are being consolidated.
The diameter of the large transfer containers will be about the same as the RPV with a height ofnearly 10m as the structures separated from the reactor core will be unitized and stored in thecontainers. Hence further substantiation of the large transfer containers is required based on theissues consolidated. Therefore detailed studies will be conducted related to the establishment of theconcept of the transfer system including the storage method, the air-tight and shielding structure of
the overall large transfer container including the lid part, the manufacturing procedures, etc. Also, thestructure of the large transfer container will be such that the inside can be decontaminated so that thecontainer can be reused. Thereafter, a full scale transfer container will be test manufactured, its
performance will be verified through element tests, its viability will be verified and issues in site
applicability will be identified.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.616
Retrieving Large Structures]② Large transfer containers
Table of Contents
⚫
⚫
⚫
⚫
⚫

Status of studies conducted up to FY2020
Issues, implementation details and results
Pre-conditions
Functions required of the large transfer containers
Steps involved in operating the dual lid in connection with transferring structures by the method of transferring
unitized large structures⚫

Structural design of the large transfer containers

⚫
⚫
⚫
⚫

Element test plan
Element test items and test details
Element test results
Policy for reflection into actual equipment⚫
⚫

Development schedule
Summary©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.617
Retrieving Large Structures]② Large transfer containers[Status of studies conducted up to FY2020]⚫ Conceptual study on the large transfer containers was conducted.
⚫ The element tests related to air-tightness of the lid part of the large transfer container were conducted during the
Ensuring Safety PJ.
Movable flange

Upper lid

Lower lid

Large transfer
container← Developed during the
Ensuring Safety PJ← To be developed during this PJ⇒ The structure of the main body of the large transfer container will be substantiated and the viability of the structure
including the manufacturing capability will be studied. Air-tightness of the container body will be verified by test
manufacturing the container.
*Ensuring Safety PJ: “Development of Technology for Further Increasing the Scale of Retrieval of Fuel Debris and Reactor
Internal Structures (Development of technology related to ensuring safety during fuel debris retrieval)”©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.618Retrieving Large Structures][Notes]Colors indicate the following
contamination levels*
R: Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones aremarked as R, Y and G.

② Large transfer containers[Issues]•
In order to transfer unitized large structures, large transfer containers with afunction for preventing the spread of contamination need to be developed.
•
Study on the confinement performance including when the large transfer containeris opened and closed, and verification of feasibility.
•
Study on manufacturing capability including processing and assembly, andverification of feasibility.
•
Method of remotely connecting the large transfer container and the lid, etc.,
handling capability.

[Implementation details]•
The pre-conditions related to the study will be consolidated.
•
Studies will be conducted on establishment of the concept of the transfer
system including the method of storing into the large transfer container
and the detailed procedures for transferring the entire large transfer
container, based also on issues studied during the Ensuring Safety PJ.
•
Structural designing of the large transfer container will be carried out.
Studies will be conducted considering decontamination of the inside of thecontainer assuming that the transfer container will be reused.
•
Element tests will be planned, the large transfer container will be test
manufactured, feasibility will be verified and issues will be consolidated.

Note) This figure explains how the large transfer container is used.
For the seating position of the work container, please refer to theconceptual diagram shown in 6.2)(1)①(a) Method of transferring
unitized large structures and the results of studying the layout of theadditional building.

Shielding cart

Transportation
cart

Y
Work
container

Container Large transfer

R

R dual lid container

G
Reference: Illustration of the main
body of the container

Weight: Approx.
390t

Φ8m

[Expected outcome]•
Presentation of a detailed process diagram of the transfer system using large transfer
containers•
Presentation of a structural drawing considering manufacturing capability.
•
Presentation of results of verification of air-tightness by means of element tests, feasibility
evaluation and issues.

7.5m

Illustration of the container

Fuel debris at the reactor
bottom

Φ6m

Φ7m
Main dimensions

Illustration of collection
at the reactor bottom

Additional shielding will be installed if
required©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.619
Retrieving Large Structures]② Large transfer containers[Pre-conditions]• Pre-conditions for the method of transferring unitized large structures are given below.
ID.

Pre-conditions

Basis

1

The structure of the container must enable storage ofthe structures cut into large pieces.
(The container must be able to store structures that areabout Φ5.5m, H5.5m.)

The structure of the container must enable storage ofunits that have been cut and transferred for every
structure using the method of transferring unitizedlarge structures.

2

The large transfer container must serve as an on-sitetransportation container for moving objects from theadditional building to another building such as thestorage building, etc.

First, it will be verified if the container is viable as an
on-site transportation container, and its applicability tostorage will be evaluated in future subsidy projects.

3

The structure of the large transfer container must be
such that it can be repeatedly used as an on-sitetransportation container.

As repeated use of the large transfer container wouldbe economical.

4

The results of studies conducted during the Ensuring
Safety PJ must be reflected as appropriate for otherbasic specifications of the large transfer container.

Will be continued in coordination with the Ensuring
Safety PJ.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.620
Retrieving Large Structures]② Large transfer containers[Notes]Colors indicate the following
contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones aremarked as R, Y and G.

[Pre-conditions]

A rough outline of the steps involved in using the large transfer container are given below.
(A) Unitized structures transferred from the PCV will be transported to the additional building and stored in large transfer containers.
(B) The structures stored in the large transfer containers will be transported on site to the New building.
(C) The structures will be removed from the large transfer containers inside the New building, they will be finely cut and stored incanisters and transportation casks.
Scope of use of large transfer containers

Shielding cart

Transportation
cart

Y

New building

To the storage facility

Additional building

Fine cutting cellContainer reused after
decontamination
Work container

R

R

Container Large transfer
dual lid container

Receiving cell

Fine cutting Canister

Transportation cask

G(A) Operations in the additional building[Details of the operations]・ The connecting parts of the structures will be cut, the structures will be liftedup using a crane and unitized large structures will be transferred from thePCV.
・ After the structures are moved over the operation floor using the transportation
cart, they will be lowered with the help of the crane in the additional building,stored in large transfer containers and delivered.
・ Empty large containers will be received, they will be connected to theadditional building, and preparations will be made for storing the transferred
structures.
Since the classification of contaminated areas is under examination, it could change in the future.

(B) On-site transportation(C) Operations in the New building[Details of the operations]・ The structures stored in the large transfer
containers will be transported on site to
the New building.
・ After being decontaminated in the New
building, the empty containers will betransported on-site.

[Details of the operations]・ The structures will be removed from the large transfer
containers.
・ The structures will be finely cut and stored in canisters andtransportation casks.
・ The transportation casks will be delivered and stored at thestorage facility.
・ The empty containers will be decontaminated and inspected, anddelivered to the additional building for reuse.

Note) This figure explains the steps involved in using the large transfer containers.
For the seating position of the work container, please refer to the conceptual diagram shown in 6.2)(1)①(a) Method of transferring unitized large
structures and the results of studying the layout of the additional building.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofRetrieving Large Structures]② Large transfer containers

No.621[Functions required of the large transfer containers]
・ A comparison of the structural outline of the large transfer container and the spent fuel transportation container used in Fukushima Unit 3 is shownin the table below.
According to the table, the structures in the large transfer container are planned to be similar to the structures required of existing transportation
containers, and it is believed that it will be feasible to use the large transfer container as a container for on-site transportation.
ID.

Item

1

Shielding structure(γ radiation source, neutronradiation source)2

Criticality prevention structure

Fukushima Unit 3

Spent fuel transportation container#①The carbon steel in the body, bottom plate and outer casing, and the stainlesssteel in the lid are γ rays shielding materials② Water in the body and the resin between the body and outer casing are theneutron shielding material

Large transfer container① γ rays shielding material is made up of carbon steel in the main body,the lid and the additional shielding.
② Neutron shielding material is made up of the resin in the main body andlid.

The basket (borated stainless steel) containing the fuel has a grid-shaped
structure that keeps the fuel in the prescribed geometric form.

The container is already filled with the required quantity of insoluble neutron
absorption material (Glass material containing B and Gd) for preventing
criticality. (Filter, filling structure, etc. need to be studied from the perspectiveof preventing obstruction of drainage during decontamination)

The heat that gets transferred to the main body of the container is mainly
dissipated by the heat transfer fin provided in the resin of the neutron shielding
part.

The necessity of the residual heat structure (heat transfer fin, etc.) depends
on the quantity of heat generated by the inclusions (According to the resultsof the rough evaluations at this point in time the heat transfer fin is not
required). If required, a ceramic heat transfer fin can be added to the side
and at the bottom of the main body of the container.

3

Heat removal structure

4

Air leakage inspection

The leakage rate from the primary lid, secondary lid and the port coverrespectively should not exceed 9 x 10-1 ref cm3/s when a pressure of 0.9MPaG ormore is applied to the sealed part of the transportation container.

Since a transportation lid + a metal Ｏ ring are used during on-sitetransportation, it is believed to be equivalent to a metal cask.

Structural strength

The possibility of occurrence of events are studied considering measures toprevent such occurrences, focusing on initiating events that are assumed to occur
during transportation, as also on handling the containers for on-site transportation,
based on the handling flow.
The containers are not meant for transportation outside the plant. They are used
exclusively for on-site transportation. Within the premises of 1F, the vehicles are
slowed down so as not to come in the way of other vehicles. Hence falls that
could occur assuming an accident during transportation are not taken into accountas a design requirement. Also, it is verified that the structural strength is sufficient
to withstand load generated while the container is being handled within the 1F
premises. Further, since measures have been taken to prevent the fall of thetransportation container, the event of falling during handling is not taken into
consideration as a design requirement.

The possibility of occurrence of events is studied considering measures toprevent such occurrences, focusing on initiating events that are assumed tooccur during transportation, as also on handling the containers for on-sitetransportation, based on the handling flow.
Since the large transfer containers are also meant exclusively for onsite transportation, just as it has been described in the left column, falls
resulting from accidents are not taken into account as a design
requirement. Also, since the container is not lifted up during transportation,and fall prevention measures are planned to be taken by using a gantry
for transportation, falls during handling are not taken into account as adesign requirement.

5©International
Research
forfuelNuclear#Source: Nuclear Regulation Authority website “Application for approval of changes
in the equipment
for Instituteremovingfrom Decommissioning
the spent fuel pool”.

6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.622Retrieving Large Structures]② Large transfer containers[Functions required of the large transfer containers]

・ The functions required of the large transfer containers and their current specifications are given below.
ID

Required functions

Items

Current container specifications

Remarks

1

It must be possible to store andtransport on site the structures
retrieved by transferring unitizedlarge structures.

Items to be transported

Dryer, separator, upper grid plate, reactor core, reactor bottom, etc.

It is assumed that reactor internal structures are stored as unitized structures.
Items besides those mentioned on the left will be studied as well considering theimpact such as the weight, dose, etc. of isolation sheet, etc.

Approximate dimensions of thecontainer

Inner diameter Φ6000 x H7500[mm]

Shape of the container is such that typical structures can be stored.

Function of maintaining boundaries

The structure must have a dual lid for maintaining the boundaries through aseries of procedures

The sealed part will be studied considering the use of a double door.

Pressure within the cell-400 [PaG]

The lid will be closed while connected with the -400Pa in the container (redzone).

5

Target leakage rate (During theoperation inside the cell in the
additional building)

0.1[vol%/h]

Set based on the design basis for the nuclear facility air management
considering that the leakage rate is around the same as the acceptable leakage
rate for the cell inside the boundary.

6

Maximum dose rate of contents

300[Sv/h]

Evaluated based on the radiation dose from the stored structures

7

Shielding thickness (γ rays)

280 [mm]

A 130mm separate additional shield will be installed beforehand for structureswith a high radiation dose.

Shielding thickness (neutron rays)

100 [mm]

Will be evaluated based on the radiation source of fuel debris.

9

Approximate weight520 [ton]

Only the main body of the container, lower lid, and transportation lid (notincluding the structures)
Structures, transportation conditions will be studied based on the total weight
including additional shielding. (Approx. 1300 ton)10

Number of times it will be used

Planned to be used multiple times

Main material of the container

Carbon steel

12

Material of the sealed part

Rubber O ring (CR)13

Decontaminability

Must have a drain and must be lined with SUS

SUS lining and drain will be installed taking into account that the inner surface
will be washed with water.

Container surface designtemperature

130 [°C]

The amount of heat generated by fuel debris is set tentatively based on
estimation. Further, with the current sealed part, the calculated temperature isapprox. 60℃. Hence it is believed that there are no issues with this specification.

2

3

4

8

11

14

It must be possible to store
structures inside the cell in the
additional building while
preventing spread ofcontamination.

Shielding must be possible
during transportation of thestructures.

Repeated use of the container
must be possible.

The design must consider
generation of heat by the fueldebris.

The main material of the container and the material of the sealed part have beenstudied during the Ensuring Safety PJ assuming the container will be used
multiple times.
The sealed part and the inner surface must be SUS clad.
Considering that the dual lid will be opened and closed multiple times andconsidering that it could fall, it was installed in a dovetail groove.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.623Retrieving Large Structures][Notes]Colors indicate the following contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y and G.

② Large transfer containers[Steps involved in operating the dual lid in connection with transferring structures by the method of transferring unitized large structures (1/7)]
The steps involved in operating the dual lid while transferring structures and the boundaries are given below.
Enlarged view of Part A(1) Preparing for carrying-in the container: Removing the safety lid
Additional building
Building cover

Movable flange
Boundary

Shielding cart

-400PaBellows

Transportation cart

Upper lid

Boundary

Water seal

Work container-150PaPassageway

Upper lidR

Sealed part ①

Since air-tightness is ensured by meansof the upper lid (and safety lid), this zone
is assumed to be “Y” which is extremely-400Pa near “G”.

Isolation
sheet

Fixed flange(Fixed to the additionalbuilding)
Boundary
Boundary

Sealedpart ③Y(G)*Safety lid

Part A

Safety lid

Safety lid -150Pa-64Pa(1) Preparing for carrying-in the container: Removing the safety lid
Movable flange is raised(2) Carrying-in the container: Carrying-in the large transfer container
R

Work container
Shielding cart

Sealedpart ③

Transportation cart

Upper lid

Isolation
sheet

Since air-tightness is ensured bymeans of the upper lid, this zone isassumed to be “Y” which isextremely near “G”.

-400PaBoundary
Y(G)*Sealed part ②
Container is carried-in

Container (with lower lid)

Part A

Lower lid
Largetransfer
container-150Pa* Assumed to be “Y” which is extremely near “G”** When the large transfer container is reused, the inside of the container may not be “G”.
Since the classification of contaminated areas is under examination, it could change in the future.

G(R)**(2)-1: Raising the movable flange(2)-2: Carrying-in the large transfer container (The container moves only in the horizontal direction)Note) This figure explains the steps involved in closing the lid of the large transfer container. (The pressure
mentioned in the diagram is an assumed value) For the seating position of the work container, please refer to theconceptual diagram shown in 6.2)(1)①(a) Method of transferring unitized large structures and the results of studying
the layout of the additional building.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.624Retrieving Large Structures][Notes]Colors indicate the following contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y and G.

② Large transfer containers[Steps involved in operating the dual lid in connection with transferring structures by the method of transferring unitized large structures (2/7)]
The steps involved in operating the dual lid while transferring structures and the boundaries are given below.
Enlarged view of Part A

Lowering of movable
flange(3) Connecting the container: Connecting the upper lid and lower lid (container)
R

Sealed part ③
Work container

Sealed part ①

Shielding cart

Sealed part ⑤

Transportation cart

Boundary
Y(G)*Isolation
sheet-400PaSealed part ④

Part A

G(R)**

Sealed part ⑥
Largetransfer
container-150Pa

Y(G)*

-64Pa

(3)-1： Lowering the movable flange(3)-2: Connecting the upper lid and lower lid(container)
Upper and lower lid areraised(4) Lifting the dual lid, opening the container

Enlarged

Shielding cart

Transportation cart

-400PaSealed part ⑤

Work container
Container
dual lidY(G)*Attached to the lower lid bymeans of a hook

Sealed part ①
R

Boundary

Part A-150PaLargetransfer
container

-64Pa
Y(G)*

Sealed part ④* Assumed to be “Y” which is extremely near “G”** When the large transfer container is reused, the inside of the container may not be “G”.
Since the classification of contaminated areas is under examination, it could change in the future.

(4)-1: Lifting the dual lid and opening the container©International
Research
Institutementioned
for Nuclear
DecommissioningNote) This figure explains the steps involved in closing the lid of the largetransfer container.
(The pressurein thediagram is an
assumed value) For the seating position of the work container, please refer to the conceptual diagram shown in 6.2)(1)①(a) Method of

6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.625Retrieving Large Structures][Notes]Colors indicate the following contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y and G.

② Large transfer containers[Steps involved in operating the dual lid in connection with transferring structures by the method of transferring unitized large structures (3/7)]

The steps involved in operating the dual lid while transferring structures and the boundaries are given below.
(5) Completely opening the container

Shielding cart

Enlarged view of Part A

Transportation cart

Sealed part ①
Work container

R

Container dual lid

Boundary-400PaY(G)*-150PaLargetransfer
container

Part A

Sealed part ④-64Pa(5): Opening the container(6) Placing the structures in the container

Shielding cart

Enlarged view of Part A

The structure is lowered

Transportation cart

-400PaSealed part ①

Work container
Container dual lid

Boundary
R-150PaLargetransfer
container

Y(G)*Part A-64Pa* Assumed to be “Y” which is extremely near “G”
Since the classification of contaminated areas is under examination, it could change in the future.

Sealed part ④(6): Lowering and placing the structures in the container
Note) This figure explains the steps involved in closing the lid of the large transfer container. (The pressure mentioned in the
diagram is an assumed value) For the seating position of the work
container, Researchplease referto theforconceptual
diagram shown in©International
Institute
Nuclear Decommissioning
6.2)(1)①(a) Method of transferring unitized large structures and the results of studying the layout of the additional building.

6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.626Retrieving Large Structures][Notes]Colors indicate the following contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y and G.

② Large transfer containers[Steps involved in operating the dual lid in connection with transferring structures by the method of transferring unitized large structures (4/7)]
The steps involved in operating the dual lid while transferring structures and the boundaries are given below.
(7) Lowering the dual lid

Enlarged view of Part A
Sealed part ⑤

Shielding cart

Y(G)*Transportation cart

Sealed part ①

Upper and lower lid areloweredWork container

Boundary-400PaContainerY(G)*dual lid

Sealed part ④-150PaLargetransfer
container

R

Part A(7)-1: Inspecting and cleaning the sealed surface (removing trash, etc.)(7)-2： Lowering the dual lid-64Pa(8) Closing the dual lid of the containerR
Shielding cart

Sealed part ③

Transportation cart

Sealed part ①-400PaSealed part ⑤
Boundary

Work container

Y(G)*Sealed part ④

Container
dual lidY(G)*Sealed part ⑥-150PaLargetransfer
container

R

Part A-64Pa(8): Closing the lid of the large container*“Y” is assumed to be infinitely near “G”
Since the classification of contaminated areas is under examination, it couldchange in the future.

Note) This figure explains the steps involved in closing the lid of the large transfer container. (The pressure mentioned in the
diagram is an assumed value) For the seating position of the work container, please refer to the conceptual diagram shown in 6.2)(1)©International
Research
for Nuclear
Decommissioning①(a) Method of transferring unitized large structures and the resultsof studying thelayoutInstituteof the additionalbuilding.

6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.627Retrieving Large Structures][Notes]Colors indicate the following contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y and G.

② Large transfer containers[Steps involved in operating the dual lid in connection with transferring structures by the method of transferring unitized large structures (5/7)]

The steps involved in operating the dual lid while transferring structures and the boundaries are given below.
(9) Separating the container: Decoupling the upper lid and lower lid

Enlarged view of Part A

Movable flange
raisedR

Sealed part ③
Shielding cart

Transportation cart

Upper lid
-400PaWork
container Since air-tightness is ensured by means of theBoundary

upper lid, this zone is assumed to be “Y”
which is extremely near “G”.

Y(G)*Container dual lid

Sealed part ②

Part AY(G)*-150PaLarge transfer
container

Sealed part ⑥-64Pa*“Y” is assumed to be infinitely near “G”

Since the classification of contaminated areas is under examination, it could change in the future.

R
Primary boundary(9)-1： Raising the movable flange(9)-2: Decoupling the upper lid and lower lid

Note) This figure explains the steps involved in closing the lid of the large transfer container. (The pressure
mentioned in the diagram is an assumed value) For the seating position of the work container, please refer to theconceptual diagram shown in 6.2)(1)①(a) Method of transferring unitized large structures and the results ofstudying the layout of the additional building.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.628Retrieving Large Structures][Notes]Colors indicate the following contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y and G.

② Large transfer containers[Steps involved in operating the dual lid in connection with transferring structures by the method of transferring unitized large structures (6/7)]

The steps involved in operating the dual lid while transferring structures and the boundaries are given below.
Enlarged view of Part A(10) Transferring the container: Transferring the large transfer container
R

Sealed part ③

Boundary
Y(G)*Container is moved
Shielding cart

Sealed part ②Y(G)*Transportation cart

Sealed part ⑥

R

Work container-400PaContainer (with lower lid)(10)-1: Moving the large container to the next cell which is the lid closing cellContainer dual lid Large transfer container

Part A-64Pa
Y(G)*-150Pa* Assumed to be “Y” which is extremely near “G”
Container
carrying in cell

Lid closing cell

Delivery cell
(Truck area)

Sealed part ⑥

R

Boundary(10)-2: Moving the large container to the lid closing cell

Since the classification of contaminated areas is under examination, it could change in the future.

Note) This figure explains the steps involved in closing the lid of the large transfer container. (The pressure mentioned in
the diagram is an assumed value) For the seating position of the work container, please refer to the conceptual diagram
shown in 6.2)(1)①(a) Method of transferring unitized large structures and the results of studying the layout of theadditional building.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.629Retrieving Large Structures][Notes]Colors indicate the following contamination levels*
R (Red): Red (high contamination) zone
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y and G.

② Large transfer containers[Steps involved in operating the dual lid in connection with transferring structures by the method of transferring unitized large structures (7/7)]
The steps involved in operating the dual lid while transferring structures and the boundaries are given below.
Enlarged view of Part A(11) Installing the secondary lid: Installing the transportation lid for on-site transportation*“Y” is assumed to be infinitely near “G”

The bolt is fastenedY(G)*Shielding cart

Transportation cart

Y(G)*Work container-400PaR

Transportation lid

Sealed part ⑦

Large transfer
Container dual lid container

Boundary

Sealed part ⑥-64Pa

The container is transported
after contamination inspection
and pressure resistance test

Part A-150PaContainer
carrying-in cell

Lid closing cell(11)-1： Installing a lid for on-site transportation on the large container(11)-2: Moving to the delivery cell after contamination inspection and air-tightness verification

Delivery cell
(Truck area)(12) Transporting to a separate building: Transporting the large transfer containers to a separate building
Fine
cutting cellWork container
Transportation cart

Shielding cart

To the storage
facility

New building

Isolation sheet-400Pa Container dual lid

Large transfer container-64Pa

Safety lid -150Pa
Since the classification of contaminated areas is under examination, it could change
in the future.

Receiving cell

Fine cutting Canister

Transportation cask(12)-1: Transporting to a separate building by means of on-site transportation(12)-2: Decontaminating the inside of the container at a separate area after removing the structures
Note) This figure explains the steps involved in closing the lid of the large transfer container. (The pressure mentioned in the
diagram is an assumed value) For the seating position of the work
container, pleaserefer
to the forconceptual
diagram shown in©International
Research
Institute
Nuclear Decommissioning
6.2)(1)①(a) Method of transferring unitized large structures and the results of studying the layout of the additional building.

6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.630
Retrieving Large Structures]② Large transfer containers[Structural design of the large transfer containers]
Structural design of the actual large transfer containers was studied.
Upon studying the manufacturing procedures based on this structure in the element tests, acontainer will be manufactured for the test with a structure such that its manufacturing capability canbe verified.
Sealed part ④
Transportation lid

A

Sealed part duringtransportation(Metal O ring)
Sealed part ⑤

Considering
manufacturing
capability, thesealed surface when
dual lid is used andthe sealed surface
during transportation
are kept the same,
SUS padding on
the sealed
surface
Lower lid
Sealed part ⑥
SUS Lining

Resin

Body

Proposed structure of the actual
large transfer container

Container flange

Outer casing

Details of Part A©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.631Retrieving Large Structures]② Large transfer containers[Structural design of the large transfer containers]
The manufacturing procedures were studied based on the structural design of the actual large transfer container.
・ Also, for the thickness of the container, plates with a thickness that enables cold bending will be bent, they will beassembled to form a cylinder, and the parts of bent plates will be pasted until the desired plate thickness is achieved, or
forging material of the desired thickness is manufactured.
・ The container body is planned to be manufactured by dividing the material vertically into 3 parts and welding those parts
together to form the body.
Bottom plate
FlangePortion welded whileassembling in theform of a cylinder

Temporary assemblyof upper body andmiddle body

Welding the middle
body and lower bodyConnecting theupper body andmiddle bodyConnecting the
middle bodyand lower body

Arranging for forging materialof the desired thickness or

Upper
body

Bending theplatesAssembling toform a cylinder

Middle
body

Lower
body

Components before
assembling the large transfer
container

Pasting theshielding plates

Proposed procedures for manufacturing large transfer containers©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.632Retrieving Large Structures]② Large transfer containers[Element test plan (Large transfer container for the element test Rough specifications)]
It was decided to manufacture the container flange with a structure
equivalent to the actual equipment based on the results of the studies
on the structure of the actual large transfer container andmanufacturing procedures.
The height of the main body of the container for the element test
was kept at approx. 4m (height of one part of the divided plate) which
was about half of 7.5m which is the height of the container for theactual equipment considering that the height was sufficient as long as
the plate can be bent and welded.

Large transfer container for the element test

Component table

Product
NumberProduct Name

Numberof units

Material

Remarks

1

Container flange

1

SF440A

Carbon steel forgedcomponent

2

Body

1 set

SS400

Bent plate in parts

3

Bottom plate

1 set

SS400

Steel plate in parts

4

Side support

1 set

SS400

5

Bottom support

1 set

SS400

350

① Container flange

The upper body of the container is manufactured in parts bybending a 50t steel plate.
② Body⑤ Bottomsupport(Mold steel)3835④ Sidesupport(Mold steel)

3635

Outer diameter of the container for the test： Φ6100

Depth of the container
for the test: 3585

Inner diameter of the container for the test: Φ6000③ Bottom plate

Large transfer container for the element test

Cross section

Bottom structure©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.633Retrieving Large Structures]② Large transfer containers
For development and test manufacturing[Element test plan (Scope of simulation of actual equipment)]
Actual equipment specifications (approximate
dimensions)ID.

Equipment

Mock-up specifications (approximate dimensions)

Simulation method for the test

1)

Movable flange➢ Diameter 9300, height 1600, weight 150ton

2)

Fixed flange➢ Diameter 11100, thickness 375, weight 170ton

3)

Upper lid

➢ Diameter 6800, height 800, weight 50 ton➢ Same as the actual equipment (Unit manufactured
during the Ensuring Safety PJ is used.)➢ Actual equipment shape is simulated.

4)

Lower lid

➢ Diameter 6800, thickness 280, weight 80 ton➢ Same as the actual equipment (Unit manufactured
during the Ensuring Safety PJ is used.)➢ Actual equipment shape is simulated.

5)

Container➢ Inner diameter 6000, thickness 280, height 7500,
weight 390 ton➢ Inner diameter 6000, thickness 50, height 3635,
weight 85 tonー

6)Lifting hook

➢ Diameter 500, height 1500

➢ Diameter 500, height 1500

➢ The shape of the connection part issimulated.

➢ Diameter 8000, height 1100, weight 46ton➢ Not simulated this time.

ー➢ Shape of the hook is simulated.

Differences with the mock-up structure for the dual lid test that was studied and tested as part of the Ensuring Safety PJ are given below.
・The height of the container body was determined considering the procedures for manufacturing the actual equipment. (Bare minimum
structure with which manufacturing capability, etc. of the container can be verified)・ A structure with which the flange part of the movable flange can be raised and lowered. (Adjustment of position can be verified with a shapethat is similar to the actual equipment)3) Upper lid

4) Lower lid

1) Movable flange2) Upper lid

3) Lower lid4) Largetransfer
container

3) Upper lid
4) Lower lid5) Simple container for the test
Illustration of the mock-up structure forIllustration of actual equipment
the Ensuring Safety PJ6) Lifting hook

1) Movable
flange(Can be raised
and lowered)6) Lifting hook
1) Movable flange(Fixed this time)5) Container forthe test

Illustration of the mock-up structure for this project©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.634Retrieving Large Structures]② Large transfer containers[Element test plan (Sealed parts to be verified through the test)]
Considering the operational steps at the actual site, the air-tightness of the following 4 sealed parts will be verified
during the element tests.
ID.

Sealed part

1

Sealed part ③

2

Sealed part ④

Air tight joint
⚫

⚫

3

4

Sealed part ⑤

Sealed part ⑥⚫

⚫

Between the upper lid
and the movable
flange➢Between the movable
flange and thecontainer flange➢

Between the upperand lower lids

Between the lower lid
and container

Operational steps that require airtightness

Method of ensuring air-tightness➢➢

The upper lid presses down the O ring with
its own weight to secure the prescribed
flattening of the O ring.

➢➢(3) Before being connected to thecontainer(9) After being separated from thecontainer

The movable flange presses down the O
ring with its own weight to secure theprescribed flattening of the O ring.

➢

The upper lid presses down the O ring with
its own weight to secure the prescribed
flattening of the O ring.

➢➢(4) Lifting up the dual lid, opening thecontainer(7) Lowering the dual lid

The lower lid presses down the O ring with
its own weight to secure the prescribed
flattening of the O ring.

➢➢(2) Carrying-in the container(10) Transferring the container➢(3) Connecting the upper and lower lids
(container)(8) Closing the lid of the large container

Remarks➢➢

Studied and tested during the Ensuring Safety PJ
The impact of raising and lowering the movable flange will
be verified in this project.

➢

Will be tested in this project.

➢➢Studied and tested during the Ensuring Safety PJ
The impact of raising and lowering the movable flange will
be verified in this project.

➢➢Studied and tested during the Ensuring Safety PJ
Will be verified using the container flange manufactured inthis project.

Sealed part ③

Sealed part ⑤

Part D

Sealed part ④

Schematic view of the actual equipment

Sealed part ⑥
Enlarged view of Part D©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.635Retrieving Large Structures]② Large transfer containers[Element test items and test details]
Test No.

Name of the test

1-1
1-2

Test details

Upper lid + lower lid
Prior verification
test

Upper lid + movable flange

1-3

Lower lid + container

1-4

Movable flange + container

Without
misalignment

2-1Comprehensivefunctionality test
2-2

Fitting
test

With misalignment

3

Air-tightness test

Remarks

Conducted to make sure that there is no defect in the equipment itself.
(Conducted as prior verification)
The sealing function and integrity are verified with the assembly of eachstand-alone equipment.
(The fitting of the stand-alone equipment with other equipment, air-tightness
and foaming are tested.)

Unit test of Part A Verified for the casewhen the dual lid is lifted up as well.
Used for the container＋ movable flange
as well
Unit test of Part B
Verified in No.1-2● Verification of whether there is abnormal sound or rattling when the lifting
hook is installed and removed● Verification of the connection and gaps, etc. when the upper lid and lower
lid are lifted up together (dual lid) with the help of a hook
● Verification of the connection and gaps, etc. when the upper lid andmovable flange are lifted up together
The above fitting is carried out with some misalignment (within 50mm fromthe center), and it is verified whether the assembly can be carried out without
any issues following the shape of the guide.

The steps involved in the operation
using the actual equipment are
simulated and the fitting and airtightness function are verified.

It is verified that air-tightness is achieved at every stage after each fitting test.
(In the actual equipment, opening of the dual lid, attachment and detachmentof the container are the conditions for determining whether air-tightness isachieved.

1) Movable
flange(Can be raised
and lowered)Part APart D

Sealed part ③

1) Movable flange2) Upper lid2) Upper lid

3) Lower lid

Part B

Sealed part ⑤3) Lower lid

Sealed part ④4) Container
4) Largetransfer
container

Pressure

Overview diagram of theactual equipment

Overview diagram of the test
apparatus assemblage

Sealed part ⑥

Enlarged view of sealed portion in the air-tightness test
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.636Retrieving Large Structures]② Large transfer containers[Element test items and test details]
Test No.

Name of the test

Test details

Fitting test

● Verification of whether there is abnormal sound or rattling when the lifting hook
is installed and removed● Verification of the connection and gaps, etc. when the upper lid and lower lid
are lifted up together (dual lid) with the help of a hook
● Verification of the connection and gaps, etc. when the upper lid and movable
flange are lifted up together

Without
misalignment

2-1Comprehensivefunctionality testWith
misalignment2-2Criteria

All equipment should fit and besmoothly positioned without any
abnormal noise.

The above fitting is carried out with some misalignment (within 50mm from thecenter), and it is verified whether the assemblage is possible without any issues
following the shape of the guide.

Checking the fitting of thehook with a camera

5) Lifting beam

Hook2) Upper lid

1) Movable flange(Can be raised
and lowered)At the time of testing withmisalignment： 50±5mm

At the time of testing withmisalignment： 50±5mm

3) Lower lid4) Container

Verification at the time of lifting the upper lid + lower lid⇒ Verification of whether there is abnormal noise or
rattling when the lifting hook is installed and removed

At the time of lifting up the dual lid⇒ Verification of the connection and gaps,
etc. when the upper lid and lower lid are lifted
up together (dual lid) with the help of a hook

At the time of lifting up the movable flange⇒ Verification of the connection and gaps,
etc. when the upper lid and movable flange
are lifted up together©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.637Retrieving Large Structures]② Large transfer containers[Element test items and test details]
Test No.
3

Name of the test
Comprehensivefunctionality test

Test details

Criteria

It is verified that air-tightness is achieved at every stage after each fitting test. (Inthe actual equipment, opening of the dual lid, attachment and detachment of thecontainer are the conditions for determining whether air-tightness is achieved.)

Air-tightness test

1) Movable flange(Can be raised and lowered)Part D pressurization
test

Here, the leakage rate (Pa/L/s) is in terms of Q: 20°C
P1: Gauge pressure (Pa) of the test piece when the measurement
starts
P2: Gauge pressure (Pa) of the test piece when the measurement
ends
Patm1: Atmospheric pressure (outside pressure) (Pa) whenmeasurement starts
Patm2: Atmospheric pressure (outside pressure) (Pa) after
measurement starts
Δt : Time from start of measurement to end of measurement (s)V: Internal volume of the test piece (L)T20: Reference temperature 293 (K)T1: Absolute temperature (K) of the gas inside the test piece whenmeasurement starts
T2 : Absolute temperature (K) of the gas inside the test piece whenmeasurement ends
q: 20℃,1 atm conversion of the leakage rate (L/s)

Part A

2) Upper lid
NoleakageEnd of testing(Sealed parts ③, ④,⑤
and ⑥ are sound)Is there any leakage?

[Reference]
Flow for identifying the location of the leak3) Lower lid

Leakage present
Part B pressurization
test(Pressure applied
only to Part B)
Leakage present in sealed
part ③ and ④

Leakage present
Leakage present insealed part ⑤

Part B

4) Container

Part A pressurization
test(Pressure applied toonly Part A)

No leakage

Quantity of leakage q ≦ 12L/h #Part D

Sealed part ③

Is there any leakage?

No leakage
Is there any leakage?

Leakage present

Bubble solution test
(Pressure is applied
to Part D,
and it is verified fromthe outside)

Leakage present insealed part ⑥

Sealed part ⑤

Pressure

Sealed part ④

Sealed part ⑥

Enlarged view of sealed part in the
air-tightness test

Outline diagram of the air-tightness test
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.638Retrieving Large Structures]② Large transfer containers

The air-tightness of the sealed parts is verified by applying pressure on Part D and verifying thefluctuations in pressure. If there is a leak, pressure is applied separately to each area (Part A, PartB) that is kept air-tight by the sealed part, and the fluctuations in the pressure are verified.

[Element test items and test details]

Part Dpressurization test

For the surrounding
environment

Upper lid
Hoisting partMovable flange

For Part A(For reference)

No leakage

End of testing(Sealed parts ③, ④,⑤ and ⑥ are sound)Is there any
leakage?

Barometer
Nitrogen cylinder

Thermometer

Micromanometer[Reference]
Flow for identifying thelocation of the leak

Thermometer

Upper
lid

Leakage present
Part A pressurization test
(Pressure applied to onlyPart A)Part B pressurization
test(Pressure applied only
to Part B)

Leakage present

For Part D

Leakage present insealed part ⑤

Leakage present insealed part ③ and ④

No leakage
Is there any
leakage?

No leakage
Is there any
leakage?

Micromanometer

Part A

Nitrogen cylinder

For Part B(For reference)

Lower lid

Thermometer

Leakage present

Part B

Leakage present
in sealed part ⑥

Micromanometer

Flow for verification of air-tightness

Nitrogen cylinder

Container main body

Bubble solution test
(Pressure is applied toPart D, and it is verified
from the outside)

Thermometer

Part D

Pressure

Air-tightness verification test
(Image illustrating pressure resistance test)

Sealed part ④

Sealed part ③

Sealed part ⑤

Sealed part ⑥

Enlarged view of sealed part in the air-tightness test
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.639Retrieving Large Structures]② Large transfer containers[Element test results]
・ Test status
Pictures illustrating the main movement steps are shown in the figure.
Movement step procedure of the element test (This procedure is repeated 6 times including 3 times with misalignment and 3 times without misalignment.)

Movement of
movable flange

Airtightness
test

Status of the guide when the movable
flange moves

Opening and closing
movement of dual lid

Airtightness
test

Before arresting thedual lid hook

Movable flange after movement + upper lid
Moving of
movable flange

After arresting the dual
lid hook

Container + lower lid after moving of
movable flange©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.640Retrieving Large Structures]② Large transfer containers

Movable flange[Element test results]
・ Fitting test

Movable flange

Upper lid

Upper lid

Movable flange

Movable flange
Upper lid

Large transfer
container

Large transfer
container
Upper lid (Lifting hook part)

Status of fitting of the movable flange

Lower lid

Status of fitting of the dual lid

Lower lid (Lifting lug part)

Status of attachment anddetachment of dual lid

It was verified that the movable flange as well as the dual lid fit at the prescribed position without any
abnormal noise, etc. following the guide even when there is some misalignment. Also, it was verified that thedual lid hook is attached and detached without any abnormal noise, etc.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.641Retrieving Large Structures]② Large transfer containers[Element test results]
・ Air-tightness test

Legend: ● Pass, ✕ Fail

The leakage rate when the pressurization method is used, is calculatedusing the following formula (#1).

V𝑇20 𝑃2 𝑃1 V𝑇20 𝑃𝑎𝑡𝑚2 𝑃𝑎𝑡𝑚1−−[𝑃𝑎・ 𝐿Τ𝑠]
Δ𝑡 𝑇2 𝑇1 ＋ Δ𝑡
𝑇2
𝑇1
𝑄
𝑞=
[𝐿Τ𝑠] Criteria: q < 0.003L/s = 12L/h
101325Q=

With芯ずれ有misalignment

Without
misalignment
芯ずれ無●+0.02 L/h
1回目
Round1
Opening and●二重蓋開閉
closingof dual lid+0.02 L/h●
Container
容器接続
connection-0.01 L/hRound2
2回目●
Opening and二重蓋開閉
closing of dual lid +0.02 L/hContainer●
容器接続
connection-0.02 L/hRound3
3回目
Opening and●二重蓋開閉
closingof dual lid+0.01 L/h
Container
容器接続
connection

Here, leakage rate (Pa/L/s) is in terms of Q: 20°C
P1: Gauge pressure (Pa) of the test piece when measurement starts
P2: Gauge pressure (Pa) of the test piece when measurement ends
Patm1: Atmospheric pressure (outside pressure) (Pa) whenmeasurement starts
Patm2: Atmospheric pressure (outside pressure) (Pa) after
measurement starts
Δt : Time from start of measurement to end of measurement (s)V: Internal volume of the test piece (sealed part) 101(L)T20: Reference temperature 293 (K)T1: Absolute temperature (K) of the gas inside the test piece whenmeasurement starts
T2: Absolute temperature (K) of the gas inside the test piece whenmeasurement ends
q: Leakage rate (L/s) in terms of 20℃ and 1 atmospheric pressure(*1)： Based on the pressure change and pressurization method
stipulated in JIS Z 2332 Leak testing method using pressurechange.

1回目
Round1Round2
2回目

Round3
3回目③ Pressure measurement

P1② Closed valve① Application ofpressure using
nitrogen cylinder④ Temperature
measurement

T1
Sealed part ③

Pressure

Sealed part ④

Air-tightness test was conducted after each equipment fitting withmisalignment as well as without misalignment. There was no leakage in anyof the tests, the judgment criteria was met and all tests were passed.

●+0.01 L/h
Opening and●二重蓋開閉
closingof dual lid+0.02 L/h●
Container
容器接続
connection+0.02 L/h
Opening and●二重蓋開閉
closingof dual lid+0.03 L/h●
Container
容器接続
connection-0.02 L/h
Opening and●二重蓋開閉
closingof dual lid
0.00 L/h
Container
容器接続
connection

Sealed part ⑤

Sealed part ⑥

Enlarged view of sealed part©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.642Retrieving Large Structures]② Large transfer containers[Policy for reflection into actual equipment]⚫ The position adjustment of the container will be set so that it aligns with the core of the building because of the LS (limit
switch) on the rail of the carrying-in cart.
⚫ The position adjustment of the dual lid will also be set so that the lifting beam + crane stop at the core of the building
because of the LS, etc.
⚫ The air-tightness when the dual lid is used will be verified by monitoring the space (Part D) that is enclosed inside thesealed part, the dual lid (between the upper lid and lower lid), and the pressure balance inside the container.
⚫ In addition to this, a dosimeter will be installed in the carrying in cell to check for leakage.
⚫ The maintenance of the dual lid crane, etc. will be carried out in the maintenance cell. The O ring of the sealed part ③ will
be replaced in the maintenance cell as it is installed on the upper lid side. Sealed parts ④, ⑤, ⑥ will be replaced together
when the container is decontaminated after the structures are removed.
Crane room (R)[Additional building]Sealed part ③
Installed on the upper lid sidein the actual equipment
considering maintainability

P

Main cell(R)

Pressure monitoring(-200Pa)

Structure

Part D#When the size of the large
structures is assumed tobe Φ5400.

Sealed part ⑤
Sealed part ④

R: -400Pa

Sealed part ⑥

Pressure
P monitoring(-150Pa)

Enlarged view of Part D* Assumed to be “Y” whichY(G)*: -150Pa

R : -400Pa

Maintenance cell

Step ① Opening the dual lid ➡
Step ② Carrying in the
Crane for lifting up theupper and lower lids
structures ➡
Step ③ Closing the dual lid ➡

Maintenance cranePartitioning door

Equipment for raising
the movable flangeY(G)*is extremely near “G”

The LS is set byaligning the crane withthe building core

There is no leakage from Space R
since the pressure balance of -150Pa >-200Pa > -400Pa is maintained.

Y(G)*: -150Pa

Carrying incell

Dual lid

Maintenance is carried out
by carrying the dual lid into
the maintenance cell while
there are no structures.

The LS is set by aligning thecarrying-in cart with thebuilding core
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.643Retrieving Large Structures]② Large transfer containers[Policy for reflection into actual equipment]
The results of studies conducted on the structure of large transfer containers based on the results of element tests areindicated in the figure below.

The transportation lid isfastened with bolts andsealed with the metal O ring

Sealed part ③：
O ring installed on theupper lid side

SUS padding on thesealed surface of thecontainer

Sealed part ⑤Resin
The inner surface ispadded with SUS
consideringdecontamination capability

Sealed part ④
The structure is such thatboundary is considered to be
halfway of the plate, and bent
plates are pasted on the outer
periphery to secure theshielding thickness.

Sealed part ⑥

Enlarged view of sealed part during work involving the dual lid

A drain is
installed taking
into accountdecontamination
capability

FlangeFlangeFigure illustrating the structure of the actual large transfer container©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.644
Retrieving Large Structures]② Large transfer containers[Policy for reflection into actual equipment]
The following main issues were identified and the response policy was studied.

List of issues identified with respect to the large transfer container
No.

IssuesResponse policy

1

Replacement and maintenance of the O ring of the sealed parts,
method of condition monitoring and cleaning of the groove

The O ring of the upper lid sealed part ③ will be replaced and the groove will becleaned after enclosing the dual lid in the maintenance cell. Further, the cleaning
equipment will be carried from the maintenance cell for cleaning the sheet surface ofthe movable flange.
The other lower lid and container sealed parts ④⑤⑥ will be handled along with thedecontamination to be carried out in the New building after the container istransported on-site and the structures are transferred.
Also, cameras will be installed in the additional building (dual lid work cell) for
monitoring the sealed surface (including the groove), to make sure that trash, etc. has
not come inside.

2

Method of decontaminating the container

After transferring the structures from the container, the container will bedecontaminated in the New building by inserting a decontamination equipment.
Before decontamination, the neutron absorbing material is planned to be removed bymeans of cleaning equipment and drained through the drain after decontamination.
(Studies will be conducted for making sure that the neutron absorbing material does
not obstruct the drain.)3

Since the structure will be changed so that the O ring of the sealed
part ③ is installed in the direction from the movable flange surface
to the upper lid sealed portion, the impact of this change needs tobe verified.

It is believed that if the groove is a dovetail groove, the O ring is not likely to fall andthus there is no impact. It will be verified once again that there is no impact on airtightness when the actual equipment will be manufactured.

4

Method of monitoring the pressure inside Part D and the dual lid(between the upper and lower lids) when the actual equipment is
used.

A Part D pressure monitoring line will be installed on the upper lid side and a anotherone will be installed for monitoring the pressure inside the dual lid. The pressuregauge will be connected and the pressure will be monitored using a camera, etc.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.645
Retrieving Large Structures]② Large transfer containers[Policy for reflection into actual equipment]⚫

The flow from placing the structures inside the large transfer container, fastening the transportation lid (secondary lid) with bolts, toon-site transportation is indicated below.
A large opening was made in the floor surface of the additional building. (Issue while studying the additional building)⚫

Surface B

800 ton craneWork container
Surface A① Transportingfrom the R/B

Cart
maintenancecell

Additional building

Passageway② Placing in
the container

GantryLarge transfer container③ Closing the lid of thedual lid container

Temporary storageof dual lid

Transportation vehicle④ Installing the outer lid/ verifying sealing
R/B

Conceptual diagram of the layoutof the additional building

Transportation cart

Dual lid
opening/closing cell

⑤ Reloading
the container

Dual lid
hoisting
accessory
maintenancecell

Dual lid
Large transfer
container➅ Transportation

Cross-section of Surface B

Transfer of large unitized structures (Cross-section of Surface A)* The pink line in the figure above corresponds to thecross-section of Surface A.
However, since the illustration of the crane andlayout of the maintenance cell are included in the
figure above, it does not completely correspond tothe cross-section of Surface A.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.646Retrieving Large Structures]② Large transfer containers[Policy for reflection into actual equipment]⚫ The structure of the transportation dolly is indicated.
⚫ The containers are reloaded on transportation dollies in the vicinity of the building for transportation. (Or an area issecured so that the containers can be directly driven into the area using dollies.)

Lid closing
cell

Truck
area

The cart passes through thegaps in the stands for the large
containers and carries thecontainers into the cell.

Opening and closing of outer
lid of container / verification ofsealing

Large transfer
container
Dual lid
opening/
closing
Transportation
cart

Truck area

On-sitetransportation
vehicleLarge transfer
containertransfer flow line

Layout of first floor of additional building©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.647
Retrieving Large Structures]② Large transfer containers◼ Development schedule: Planned: Actual

FY2021

FY2022

Study items
4

Major milestones

5

6

7

8

9

10

11

12

1

2

Interim Report
▼

3

4

5

Interim Report
▼

6

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final
report
▼1. Conceptual study
2. Element test plan
3. Test preparation /Test manufacturingof test equipment
4. Element tests
5. Summary

Remarks

・ Element tests were completed in December 2022.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.648
Retrieving Large Structures]② Large transfer container: Summary➢ Pre-conditions pertaining to large transfer containers were consolidated in FY2021 and the development
policy and method of using them were studied. Also, the aspects to be covered by the simulation during
the test were studied considering the structure of the large transfer containers, their manufacturing
procedure and the method of using them. Since the step of opening and closing the container by moving
the dual lid is important in terms of air-tightness while using the large transfer containers, it was planned toverify air-tightness during the step of opening and closing the container by moving the dual lid, byconducting element tests using a container manufactured for the element tests.
➢ The structural designing of the actual large transfer container was carried out considering the
manufacturing capability and the method of using it.
➢ The feasibility of the large transfer container was verified by conducting element tests.
● As a result of the fitting test, it was verified that the equipment can fit as expected when the equipment
is operated simulating the steps involved while operating the actual equipment, and that the container canconnect to the prescribed location following the equipment guide even if there is some misalignment.
● As a result of the air-tightness test, it was verified that the rate of leakage at Part D (the sites sealed bysealed parts ③, ④, ⑤, ⑥) at the above-mentioned fitting position can meet the reference value.
➢ Issues in application to actual equipment were identified, and the items to be reflected into the container
specifications and equipment design of the actual equipment were consolidated.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.649
Retrieving Large Structures]③ Large transportation equipment
With respect to retrieving fuel debris and reactor internal structures, in order to enhance thethroughput using the top access method, the method of transferring unitized large structures is being
studied as part of the development being undertaken since FY2019. To make this method possible,
large structures need to be separated from the reactor and transferred, however, the largetransportation equipment inside the R/B that will be used for transferring those structures needs to be
developed so that the structures separated from the reactor can be loaded on it as unitized
structures, and it can distinguish the transportation route that requires containment and shielding at
the air-tight gate.
The large transportation equipment needs to be small and light in order to reduce the load on theoperating floor of the R/B, and its traveling function should not be affected by deformation, etc.
caused when heavy structures are mounted on it. Also, if the transportation equipment will be like acart, generally one that is towed with a wire can have a lower floor as compared to the automated one,and is suitable for reducing the size as well. However, if an air-tight gate will be installed forcompartmentalizing contaminated areas, such transportation equipment will be difficult to use. Suchpreconditions for the large transportation equipment and items that need to be developed for its use
will be studied and consolidated, the methods for properly transporting large and heavy contaminatedstructures including their applicability when there is an air-tight gate will be investigated and studied,the structure of the transportation equipment including the drive mechanism will be studied andelement tests will be conducted for evaluating the on-site applicability of the large transportationequipment, and for consolidating related issues.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.650
Retrieving Large Structures]③ Large transportation equipment
Table of Contents⚫
⚫

Issues, implementation details and results
Pre-conditions

⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫

Functions required of the shielding/transportation cart
Drive system for the shielding/transportation cart
Comparative evaluation of the drive systems for the shielding/transportation cart
Study of the structure of the shielding/transportation cart
Remote connector system element test plan
Status of element tests
Element test results
Issues⚫
⚫

Development schedule
Summary©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.651Retrieving Large Structures]③ Large transportation equipment[Issues]•
Since the items to be transported are heavy, the impact of loading heavy items on the large transportation equipment needs to beconsidered.
•
Maintaining air-tightness by means of the air-tight gate in the passageway and transporting heavy items by means of the largetransportation equipment, both need to be accomplished together.
•
The floor of the large transportation equipment needs to be made as low as possible considering the height of the ceiling of thepassageway and the hoisting clearance of the work container.
[Implementation details]•
The pre-conditions and required functions of the large transportationequipment that do not hinder the function of the air-tight gate(compartmentalizing the contaminated areas by maintaining air-tightness)
inside the passageway will be consolidated.
•
Existing technology and track record, etc. related to the method of transporting
large and heavy structures will be investigated and studied.
•
The configuration of the large transportation equipment including the drive
mechanism will be studied.
•
The method for reducing the size and weight of the large transportationequipment will be studied for reducing the load on the R/B operation floor.
•
The impact of loading heavy items on traveling will be studied.
•
The feasibility of placing the large transportation equipment and its drive
mechanism inside the passageways will be studied.
•
The elements that need to be developed in particular will be identified fromamong the large transportation equipment, element tests will be planned andimplemented for verifying the application to the actual equipment at said
location, on-site applicability of the large transportation equipment will be
evaluated and issues will be consolidated.

Crane(Passageway)

Shielding cart
Passageway

Transportation cart
(Localized shielding)(Note) “Large transportation equipment” refers to“Shielding cart” and “Transportation cart”.

[Expected outcome]• Results of evaluating the on-site applicability of large transportation equipment, and related issues©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.652Retrieving Large Structures]③ Large transportation equipment[Pre-conditions]• Pre-conditions pertaining to the design of the large transportation equipment (shielding/transportation cart) areindicated below.
ID.

Pre-conditions

Remarks

1

An additional building for the top access method should be set up in
addition to the additional building for the side access method.

In the case of the top access method, transferring unitized structures isbeing considered. Hence it would be difficult to use the delivery
equipment in common with the side access method.

2

A frame should be installed so that the load of the passageway in which
retrieval equipment, etc. will be installed is supported by the groundsurface. The transportation cart travels on the frame.

Considering the acceptable maximum load of the operation floor, it will
be difficult to support the load of the passageway.

3

The transportable weight should be studied considering that large heavy
structures and work containers will be transported.

The design should consider the maximum size and maximum
temperature so that large heavy structures and work containers can betransported.

4

An air-tight gate#2 should be installed in the passageway forcompartmentalizing contaminated areas.

The configuration of the large transportation equipment that does nothinder the function of the air-tight gate should be studied.

#2: This year, the shielding/transportation cart were studied assuming that the air-tight gate is a simple shutter.
The detailed configuration of the air-tight gate will be studied next year onwards, and the results of thestudies will be reflected appropriately in the structure of the shielding/transportation cart.
Crane
Shield[Thickness:
Iron 270mm]#1: The maximum size andmaximum weight that is loaded on
the large transportation equipment(Assuming the bottom is being
removed)Maximum size: Φ6040mm x
H7770mm
Maximum weight: 800 ton[Maximum size and weight loaded]

800 ton craneAir-tight gate
Crane
Cart
maintenancecell

Shielding
cart

Transportation
cart

Gate and rail interferingwith each other[Illustration of large transportation equipment]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.653Retrieving Large Structures]③ Large transportation equipment[Functions required of the shielding/transportation cart]⚫ The function required of the shielding/transportation cart and the corresponding items of comparative evaluation of thedrive systems for the shielding/transportation cart described later are mentioned in the table below.
[List of functions required of the shielding/transportation cart]
No.

Required functions

Details

Items of comparative evaluation of the drive systems

1

Remotely operated traveling
function① Must be able to travel by remote operation with internal / external power① Extent of difficulty in traveling by remote operation

2

Moving between cells andcontrolling spread ofcontamination① Must be able to move across cells② Must be able to travel even if the passageway is sloping (assuming about 1/1000)③ The shielding/transportation cart must be able to be controlled independently④ Must avoid interference with the air-tight gate that compartmentalizes the cell
⑤ Must be able to control expansion of the contaminated area if it interferes with the air-tightgate⑥ Must be able to control the spread of radioactive materials to the outside if there is athrough hole in the cell

① Extent of difficulty in transportation between cells② Extent of difficulty in stopping on slopes③Extent of difficulty in independently controlling theshielding/transportation cart
④ Interference with the air-tight gate
⑤ Risk of expansion of the contaminated area (inside thecell)⑥ Risk of expansion of the contaminated area (outside thecell)(Inside/outside the cell)

3

Positioning on the well

① The shielding/transportation cart must be able to stop within a stipulated range on thewell.

① Positioning accuracy

4

Transportation of large heavy
structures (tentative value: 800
ton)① Must be able to move upon being loaded with large heavy structures and the work
container② It must be possible to control deflection of the transportation cart resulting from loading oflarge heavy structures, or the cart must be able to travel even if it gets deflected.

① Extent of difficulty in transporting large heavy structures② Omitted (Will be dealt with by means of the structure of
the shielding/transportation cart)

5

Shielding the well

① It must be possible to control the radiation dose from inside to reactor to the passageway
by stopping the shielding/transportation cart on the well.

① Omitted (Will be dealt with by means of the structure of
the shielding/transportation cart)

6

Maintenance by remote
operation / emergency retrieval① It must be possible to carry out maintenance of the equipment contributing to theoperation of the shielding/transportation cart by remote operation.
②It must be possible to retrieve the shielding/transportation cart back to the additionalbuilding if equipment contributing to the operation of the shielding/transportation cart breaks
down.

① Extent of difficulty in maintaining and replacing the drive
unit by remote operation② Extent of difficulty in retrieving theshielding/transportation cart

7

Manufacturing capability of thedrive unit and feasibility ofplacement① It must be technologically possible to manufacture the drive unit.
② The scale of the equipment must be such that it can be placed between the passageway
and the additional building.

① Extent of difficulty in manufacturing (including the airtight gate)② Extent of difficulty in placement feasibility©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.654Retrieving Large Structures]③ Large transportation equipment[Drive system for the shielding/transportation cart]⚫ The drive systems (a) to (g) mentioned below were studied as the drive systems having the required function (inparticular, functions that need to be fulfilled by the drive system) of the shielding/transportation cart mentioned above,
while referring to existing technology and track record.
[Proposed drive systems for the shielding/transportation cart (1/2)]
Drive
system(a) Remote connector system(B) Wire transportation system(c) Screw shaft type transportation system

PowerElectric motor (power supply through the connector)

Towed by a wire

Rotation of screw shaft

Overview• The cart is moved by repeatedly
connecting/disconnecting the power supply connector
installed above the cell and the connector insertion
port in the front and back of theshielding/transportation cart by remote operation.

• The shielding/transportation cart is moved by operating
the wire that passes through the cell wall.

• The screw shaft is rotated, and the driving force istransmitted to the shielding/transportation cart via the half
nut installed on the shielding/transportation cart.

Issues• The feasibility of remotely connecting/disconnecting
the connector on an actual equipment scale isuncertain.
• Maintenance of the power supply connector /cableveyor is difficult inside the cell.

• Wire replacement by remote operation is difficult.
• Securing space for placing the wire and drive unit for theshielding/transportation cart is difficult.

• Manufacturing large and horizontal screw shaft is difficult.
• Securing space for placing the wire shaft for theshielding/transportation cart is difficult.

Conceptual
diagram©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.655Retrieving Large Structures]③ Large transportation equipment[Drive system for the shielding/transportation cart][Proposed drive systems for the shielding/transportation cart (2/2)]
Drive
system(d) Wire drive system(e) Cable power supply system(f) Trolley system(g) Pin gear system

Conceptual
diagram
Air-tight gateWorkcontainer

Sheet forensuring airtightness in thedrive chamber

Wire

Work
container

Transportation
cart

Drive
chamberDrive unitWork
container

Trolley

Passageway
Ceiling

Passageway
CeilingWorkcontainer
Pin gear

Air-tight
gate

Transportation
cart

Cable coverAir-tight gateRail

Air-tight
gate

Passageway
Floor

Cable

Pin rack
Transportation
cart

Toughroller

Passageway
Floor

Power

Towed by a wire

Electric motor (power supply throughthe cable)

Electric motor (power supply throughthe trolley)

Rotation of pin gear

Overview• The shielding/transportation cart ismoved by connecting theshielding/transportation cart to thewire under the cell floor (or in theside wall of the cell) and operating
the wire.

• Power is supplied through the cableto the electric motor mounted on theshielding/transportation cart.

• Power is supplied through the trolley
mounted on theshielding/transportation cart.

• The pin gear installed on the sidewall of the cell is rotated while it isbiting into the pin rack on theshielding/transportation cart.

Issues• The risk of expansion of thecontaminated area passing
through the drive chamber is high.
• If the drive chamber is installed
under the floor, the risk ofinterference of the drive unit andthe well opening is high.

• Replacement of the cable by remote
operation is difficult.
• Independent control of theshielding/transportation cart isdifficult.

• As the trolley is large for remotehandling, its replacement by remote
operation is difficult.

• Handling the penetration shaft while
maintaining air-tightness during
maintenance/replacement of thedrive unit outside the cell is difficult.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.656Retrieving Large Structures]③ Large transportation equipment[Comparative evaluation of the drive systems for the shielding/transportation cart]⚫

Evaluation results in line with the evaluation items pertaining to the drive systems mentioned earlier are indicated below (Only those items in which there ismajor difference are listed).

⚫

In particular, (a) Remote connector system and (f) Trolley system which have minor issues, were considered as promising drive systems.

⚫

Of the 2 systems mentioned above, since (a) Remote connector system is believed to be more promising as a drive system with greater versatility interms of supplying water and air to the transportation cart, etc., the structure of the shielding/transportation cart was studied and element tests wereconducted considering this drive system.
Content in red: Items that have
major issues in particular[Results of comparative evaluation of the drive systems]
Drive system(a) Remoteconnector system(b) Wiretransportation
system(c) Screw shaft typetransportation
system(d) Wire drive system(e) Cable power
supply system(f) Trolley system(g) Pin gear system

Extent ofdifficulty in
manufacturing (including
the air-tightgate)〇: Comparatively
easy(Minor issues inmanufacturing)△: Comparatively
difficult(Issues in maintaining
air-tightness where thewire passes throughthe cell)▲: Difficult(Manufacturing thelong and horizontal
screw shaft is difficult.)〇: Comparatively easy
(Minor issues inmanufacturing)△: Comparatively
difficult(Issues in the opening
for the cable in the airtight gate)〇: Comparatively easy
(Minor issues inmanufacturing)〇: Comparatively easy
(Minor issues inmanufacturing)

Extent ofdifficulty inplacement
feasibility△: Comparatively
difficult(The risk ofplacement not being
feasible increases if
the number ofcables increases.)▲: Difficult(Issues in securing
space for placement of
the drive system within
and outside the cell)▲: Difficult(Issues in securing
space for the screw
shaft, screw shaft
penetration part, andthe bearing)▲: Difficult(There is a risk ofinterference with thewell opening when
multiple drive units are
required)△: Comparatively
difficult(Space for laying thecables for theshielding/transportation cart needs to be
secured.)△: Comparatively
difficult(The risk of placement
not being feasible
increases if thenumber of trolleys
increases.)△: Comparatively
difficult(Space for installingthe drive units needs
to be secured)

Extent ofdifficulty inmaintaining
and replacing
the drive unit
by remote
operation△: Comparatively
difficult(Improvements canbe made bymodifying thestructure so that
replacement is notnecessary and sothat attachment anddetachment as asingle unit ispossible.)▲: Difficult(Changing the wire by
remote operation isdifficult (Method ofchanging the wireconsidering control of
spread ofcontamination outside
the cell, andattachment anddetachment of thetransportation unit byremote operation.))△: Comparatively
difficult(A structure for straightconnection of thescrew shaft isnecessary)▲: Difficult(Changing the wire by
remote operation isdifficult (detachmentfrom the drive unit byremote operation,access to the drive
chamber))▲: Difficult(Changing the cable byremote operation isdifficult (Retrieving thecable when it is
disconnected))△: Comparatively
difficult(Studying a structurethat does not needreplacement and thatenables attachment
and detachment as asingle unit)▲: Difficult(Handling thepenetration shaft
during drive unit
maintenance is difficult(Work of replacement
while maintaining airtightness)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of
No.657Retrieving Large Structures]③ Large transportation equipment[Study of the structure of the shielding/transportation cart ①]⚫
⚫
⚫

The shielding/transportation cart# was made as light in weight as possible with a structure as shown in the figure below (Cart weight: approx. 547ton).
If the shielding/transportation cart is made even more lighter, as almost the entire shielding/transportation cart is made up of strength members, thestrength members themselves need to be worked on. As a result, deflection, etc. that is important for the design is likely to lead to deviation from theacceptable values.
As a measure to prevent the shielding/transportation cart from overturning, a structure similar to the lug for preventing the wheels from coming off andfloating up needs to be adopted.
Wheel

B
Water seal
Additional
girderAdditional
girderAuxiliarybeam

A-A cross-section

A

A

ShieldingComing off of thewheels/overturning of the cart
is prevented by adopting a
structure similar to the lug forpreventing the wheels fromcoming off and floating up.

Enlarged

Auxiliarybeam

Lug forpreventing
the wheels
from coming
off andfloating up

MaingirderB

Work
container[Planar view of the transportation cart]#: The shielding cart has a structure in which the water seal is eliminated from thestructure of the transportation cart mentioned above

B-B cross-section[Cross-sectional view of the transportation cart (Top:AA cross section, Bottom]

Rail©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofRetrieving Large Structures]③ Large transportation equipment
Shielding
cart[Study of the structure of the shielding/transportation cart ②]⚫ Structural drawing of the transportation cart, and layout
drawing of the passageway are indicated.
Transportation cart

Water seal #No.658Transportation
cart
Well
opening

Rail

Cableveyor[Layout drawing of the shielding/transportation cart]

Wheel[Structure drawing of the transportation cart]

Upper connector
BOX[Impact on traveling when large heavy structures
are mounted]
Due to the deflection of the transportation cart, theupper connector BOX tilts and is likely to hinder
attachment and detachment of the upper/lower
connector BOX by remote operation.
→ Whether or not the upper/lower connector
BOX can be attached and detached by remote
operation when the transportation cart isdeflected, was verified by conducting element
tests.

Wheel

Enlarged
Inner side of theshielding/transportation cart

[Cross-section of the shielding/transportation cart]
Lower connector
BOX

Cableveyor#: Mounted as equipment for preventing spread ofcontaminants present at the bottom of the work container©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept ofRetrieving Large Structures]③ Large transportation equipment

No.659[Study of the structure of the shielding/transportation cart ③]⚫

The items to be verified in the element tests were consolidated based on the results of the studies on the shielding/transportation cart.

IllustrationNote) The shift and tilt are overstated

Items to be verified

ReasonWhether or not theconnector can be connected
when the stopping position
shifts

The stopping precision (shift in the stopping position as against the target stopping position) of theshielding/transportation cart, the structure of which was studied, is assumed to be approx. ± 6 mmbased on results of calculations.
→ When the shielding/transportation cart stops at the target stopping position (when shift is 0mm), it
has stopped at a position where the lower connector BOX is right below the upper connector BOX.
→ When the shielding/transportation cart stops at a position that has shifted from the target stopping
position, as the upper connector BOX and lower connector BOX becomes misaligned in a similarmanner, the shift needs to be absorbed while making the connection.

(Test item No. 4)

Lateralview

Upper connector
BOX

Occurrence ofa shift

Lower connector
BOX

Whether or not theconnector can be connected
when there is deflection(Test item No. 5)

The transportation cart, the structure of which was studied, gets deflected when large heavy
structures are mounted on it.
→The extent of deflection (angle of inclination) is assumed to be approx. 0.14° in the direction of
travel and at right angles, referring to the “Limit of deflection of the overhead crane” mentioned in
the industry standards for cranes.
→ Due to the said deflection, since the upper connector BOX that is mounted on the transportation
cart is tilted with respect to the lower connector BOX, the tilt needs to be absorbed while making theconnection.

Front view

Upper connector
BOX

Occurrence ofa tiltLower connector
BOX©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.660
Retrieving Large Structures]③ Large transportation equipment[Remote connector system element test plan ①]⚫ The purpose of the element tests is to verify the feasibility of connection and disconnection of the connector by remote
operation and movement of the cart between cells on an actual equipment scale.
⚫ Structural outline of the element test equipment is indicated in the figure below.
(Equivalent to actual equipment: Upper and lower connector BOX, rail (sliding platform)(1/4 scale: Span of the connector box, length of the sliding platform)
Upper connector BOX

Upper connector BOX

Rail (Slider platform)
Guide
Cell 2Cell 1
Lower connector BOX

Trolley[Remote connector system element test equipment
bird’s eye view]

Multicoupler
Lower connector BOX

Cell 1

Cell 2Cell 2Connector

Cell 3

Cableveyor

Guide pin[Remote connector system element test equipment schematic diagram][Upper/Lower connector BOX schematic diagram]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.661
Retrieving Large Structures]③ Large transportation equipment[Remote connector system element test plan ②]⚫ The procedures for connecting the remote connector during the element tests are indicated below.
⚫ The following procedures are performed for the upper connector BOX when its placement is appropriate/when there isa shift in position/when there is a tilt respectively.
⚫ The shift in position is assumed to be the shift in position while stopping the shielding/transportation cart the structureof which was studied.
⚫ The tilt is assumed to be the deflection of the transportation cart when large heavy structures are mounted on it.

[Procedures for connecting the connector BOX by remote operation]
STEP① Positioning② Lowering the upper connector BOX

Illustration
TrolleyUpper connector
BOX

TrolleyUpper connector
BOX

Guide
Guide pin

Lower connector
BOX

Details

The upper connector BOX is positioned by horizontally moving
the cart.
After completing the positioning, the upper connector BOX islowered, and it is confirmed that the guide pin of the lower
connector BOX passes through the guide part of the upper
connector BOX.

The connector is connected by only lowering the upper
connector BOX.
Power is supplied and signals are transmitted to the cart and it
is verified that the cart can move according to the instructions(that the connector connection has been completed).

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.662
Retrieving Large Structures]③ Large transportation equipment[Remote connector system element test plan ③]⚫ The test items and judgment criteria mentioned in the table below were set.

[Element test

List of test items]

No.

Test Item

Details

Criteria

1

Whether or not
the connector
can beconnected byremoteoperation

It is verified that the power supply connector can be connected byremote operation.

①: There should be no interference while lowering the upper connector BOX②: The position of the upper connector BOX should be according to the design after it has been lowered.
③: The power lamp on the control panel should be lit up after the connector is connected.
④: The cart should move forward without any issues in response to instructions for moving forward.

2

Whether or not
the connector
can bedisconnectedby remote
operation

It is verified that the power supply connector can be disconnectedby remote operation.

①: The position of the upper connector BOX should be according to the design after it has been lifted up.
②: There should be no interference while lifting up the upper connector BOX③: The cart should move forward without any issues in response to instructions for moving forward.
④: The connectors and couplers should not be damaged and deformed.
⑤: There should be no harmful scratches on the surface of the connectors and couplers.

3

Whether or not
the cart canmove between
cells

It is verified that transportation cart can move to adjacent cells by
repeating the procedures for connecting/disconnecting theconnector by remote operation.

①: The cart should be able to move from Cell 1 → Cell 2 → Cell 3 → Cell 2 → Cell 1 by remote operation only.
②: The horizontal shift in the stopping position of the cart from the stipulated stopping position to the actual stopping
position at each cell should be ±10mm (fitting precision of the guide) or less.
③: The cart should completely cross over the gaps in the rail (The rear wheels of the cart when the cart is moving forward
should be on the rail inside the cell into which the cart is moving)

4

Whether or not
the connector
can beconnected
when there is a
shift in the
stopping
position

It is verified that the connector can be connected even when the
stopping position of the cart is intensionally shifted in the range of±10mm (range of the shift in position anticipated in the actual
equipment).

①: The power lamp on the control panel should be lit up.
②: The cart should move forward without any issues in response to instructions for moving forward.
③: There should be no interferences besides the guide pin and the part in which it fits.

5

Whether or not
the connector
can beconnected
when there isdeflection

It is verified that the connector can be connected even when theupper connector BOX is tilted with respect to the lower connector
BOX anticipating deflection of the cart in the actual equipment. (TheBOX is tilted 0.5° considering the deflection in the actual
equipment and is perpendicular to the rail.)①: There should be no interference while lowering the upper connector BOX②: The position of the upper connector BOX should be according to the design after it has been lowered.
③: The power lamp on the control panel should be lit up after the connector is connected.
④: The cart should move forward without any issues in response to instructions for moving forward.
⑤: The connectors and couplers should not be damaged and deformed.
⑥: There should be no harmful scratches on the surface of the connectors and couplers.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.663
Retrieving Large Structures]③ Large transportation equipment[Remote connector system element test plan ④]⚫
⚫
⚫

The shift in the stopping position of the shielding/transportation cart is replicated by manually shifting the cart (considering the safety factor) ±10 mm.
The deflection of the cart is replicated by tilting the lifting equipment for the upper connector BOX (considering the safety factor) approx. 0.5°.
A shim is inserted in the holding part for the lifting equipment and the cart for tilting the lifting equipment.

TrolleyUpper connector BOX

Upper connector BOX
Holding part of the lifting
equipment (top)TrolleyUpper connector BOX

Lower connector BOX

Approx. 0.5°

[Method of replicating the deflection (tilting of connector)

Shim inserted only inlower part

Schematic diagram]

Lower connector BOX
Holding part of the lifting
equipment (bottom)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.664
Retrieving Large Structures]③ Large transportation equipment[Status of element tests (While verifying whether or not the cart can move between cells)]
Trolley: Connector BOX

Trolley

Cell 1

Cell 2Cell 3Cell 1

Cell 2④ Movement of the cart (To Cell 2)① Initial condition
Trolley

Cell 1

Trolley

Cell 2Cell 3② Movement of the cart (In between Cells 1 and 2)

Cell 1

Cell 2Cell 3⑤ Changing of the connection of the connector BOX (Cell 2）

Trolley

Cell 1

Cell 3

Trolley

Cell 2Cell 3③ Changing of the connection of the connector BOX (In between Cells
1 and 2)Cell 1

Cell 2Cell 3

Movement of the transportation cart (In between Cells 2 and 3)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.665
Retrieving Large Structures]③ Large transportation equipment[Element test results ①]⚫
⚫
⚫

After connecting the connector, power was supplied and signals were transmitted to the transportation cart through the connector,
and it was verified that the transportation cart can be operated according to the instructions.
While 2 connectors were connected to the transportation cart, one of the connectors was disconnected by remote operations.
Power was supplied and signals were transmitted through the other connector, and it was verified that the transportation cart canmove independently of the connector that was disconnected.
It was verified that the connector can be connected even when the stopping position of the cart is intensionally shifted in therange of ±10mm (range of the shift in position anticipated in the actual equipment), and even when the upper connector BOX istilted approx. 0.5°.

At the time of testing with misalignment： 10mm

At the time of thedeflection test：
approx. 0.5°
# Overstateda. Before connecting

b. After connecting[Status of connecting the remote connector]©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.666
Retrieving Large Structures]③ Large transportation equipment[Element test results ②]⚫
⚫
⚫

Element tests were conducted on connecting and disconnecting the remote connector.
The results of all the element tests for all test items met the judgment criteria.
The feasibility of connecting and disconnecting the connector and movement of the cart between cells on an actual equipment
scale was verified based on the judgment results.

No.

Test Item

Criteria

Test results

1

Whether or not the connector
can be connected by remote
operation①: There should be no interference while lowering the upper connector BOX②: The position of the upper connector BOX should be according to the design after it has
been lowered.
③: The power lamp on the control panel should be lit up after the connector is connected.
④: The cart should move forward without any issues in response to instructions for moving
forward.

The judgment criteria were met.
After connecting the connector, power was supplied and signals were transmitted to the transportation cart
through the connector, and it was verified that the transportation cart can be operated according to the instructions.

2

Whether or not the connector
can be disconnected byremote operation①: The position of the upper connector BOX should be according to the design after it has
been lifted up.
②: There should be no interference while lifting up the upper connector BOX③: The cart should move forward without any issues in response to instructions for moving
forward.
④: The connectors and couplers should not be damaged and deformed.
⑤: There should be no harmful scratches on the surface of the connectors and couplers.

The judgment criteria were met.
It was verified that while 2 connectors were connected to the transportation cart, one of the connectors can be
disconnected by remote operation.
Also, it was verified that after changing over the connector, the transportation cart can be operated by supplying
power and transmitting signals through the other connector.

3

Whether or not the cart canmove between cells①: The cart should be able to move from Cell 1 → Cell 2 → Cell 3 → Cell 2 → Cell 1 byremote operation only.
②: The horizontal shift in the stopping position of the cart from the stipulated stopping
position to the actual stopping position at each cell should be ±10mm or less.
③: The cart should completely cross over the gaps in the rail (The rear wheels of the cart
when the cart is moving forward should be on the rail inside the cell into which the cart ismoving)

The judgment criteria were met.
It was verified that movement is possible by remote operation alone from the cell at one end to the cell at the otherend by repeating the procedures for connecting/disconnecting the power supply connector.

4

Whether or not the connector
can be connected when there
is a shift in position①: The power lamp on the control panel should be lit up.
②: The cart should move forward without any issues in response to instructions for moving
forward.
③: There should be no interferences besides the guide pin and the part in which it fits.

The judgment criteria were met.
It was verified that the connector can be connected even when the stopping position of the cart is intensionallyshifted in the range of ±10mm (range of the shift in position anticipated in the actual equipment).

5

Whether or not the connector
can be connected when there
is deflection①: There should be no interferences besides the guide pin and the part in which it fits.
②: The position of the upper connector BOX should be according to the design after it has
been lifted up.
③: The power lamp on the control panel should be lit up.
④: The cart should move forward without any issues in response to instructions for moving
forward.
⑤: The connectors and couplers should not be damaged and deformed.
⑥: There should be no harmful scratches on the surface of the connectors and couplers.

The judgment criteria were met.
It was verified that the transportation cart can be operated according to the instructions by supplying power andtransmitting signals to the transportation cart through the connector after connecting the connector, even when theupper connector BOX is tilted approx. 0.5° with respect to the forward motion of the cart.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.667
Retrieving Large Structures]③ Large transportation equipment[Issues (Items to be studied in the future）]- Evaluation results related to on-site applicability ⚫

Prospects of being able to move the transportation cart (deflection and stopping precision simulated in the element tests) on which

800 tons of large heavy structures were mounted between cells by remote operation by means of the remote connector system,
were obtained.

- Issues ⚫

Equipment (robot) for replacing the lower connector BOX and cableveyor by remote operation needs to be studied.

(As a concept of replacement by remote operation, it is anticipated that the lower connector BOX and cableveyor will be removed
together from the connector BOX on the passageway side with the help of a robot, and thereafter, these will be mounted on theemergency retrieval cart and transported to the additional building.)⚫

The feasibility of connecting the upper/lower connector BOX by remote operation to cables that will be present in the actual
equipment needs to be verified.

⚫

The functionality achieved by combining the air-tight gate and the drive unit of the shielding/transportation cart needs to be verified.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.668
Retrieving Large Structures]③ Large transportation equipment: Planned: Planned (after revision)*: Actual◼ Development schedule
FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

FY2022
12

Interim Report
▼

1

2

3

4

5

Interim Report
▼

6

7

8

9

10

11

Interim Report
▼

12

1

2

3

Final
report
▼1. Conceptual study
2. Element test plan
3. Test preparation /Testmanufacturing oftest equipment
4. Element tests
5. Summary

Remarks

・ Since the study of the steps involved in carrying-in/out and consolidation of issues required time, the design ofthe test plan was started from FY2022.

* The plan was revised to reflect the progress status of the studies.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of Technology for Realizing the Concept of No.669
Retrieving Large Structures]③ Large transportation equipment➢ Pre-conditions pertaining to the structure of the large transfer equipment were put together in
FY2021 and the development policy was studied.
➢ The required functions of the large transportation equipment were studied and consolidated. Also,
potential drive systems for the shielding/transportation cart that can be used in largetransportation equipment were identified by investigating existing technology/track records,
further comparative evaluation was carried out based on the required functions that have been
consolidated, and the drive system that was found to be promising in particular was studied.
➢ It was decided that element tests will be conducted focusing on the remote connector system inwhich power is supplied through the remote connector, and a test plan was designed (test items,
verification details, judgment criteria were consolidated).
➢ Element tests were conducted to verify feasibility. Issues in application to the actual equipment
were identified and reflected into the equipment design for the actual facility.

©International Research Institute for Nuclear Decommissioning7. Summary

No.6701） Development of side access method(1) Development of the method of installing access equipment① Installation of large heavy structures➢ The structure was detailed focusing on the boundary (connected parts, assembled parts and installed parts)of the cell adapter, shielding door and fuel debris retrieval cell that form the access equipment.
➢ The access equipment and other fuel debris retrieval equipment cells need to be installed accurately in astraight line between the pedestal opening and the X-6 penetration opening, in order to establish the shortest
access route.
Hence, the installation procedures and structure were studied, and proposals on the structure and installation
feasible on the whole were developed considering the fitting accuracy.
➢ As a part of the study for enhancing throughput, the work carried out inside the cells was detailed for
improving the accuracy of the results of calculating throughput.
➢ The work steps involved in installing large heavy structures were detailed and revised, issues in each step
were identified, and element tests (establishment of the installation reference location, verification of the 3D
processing technique for the cell adapter flange, verification of whether or not insertion is possible, andoverall structure) for determining the policy for responding to the issues and for verifying it were designed
and conducted.
➢ Since the work of installation will be carried out under high radiation dose environment, the cell adapter willneed to be installed by remote operations. Hence the detailed steps involved in the installation procedure
were organized and related issues were consolidated. Also, a test plan for clarifying the required conditions
for the remotely controlled equipment was created based on a structure that was substantiated and the tests
were conducted.

©International Research Institute for Nuclear Decommissioning7. Summary

No.671

1） Development of side access method(1) Development of the method of installing access equipment (Continued)② PCV connection sleeve remote installation and welding

Remote installation of sleeve➢ In FY2021, the requirements (pre-conditions) for remote installation of the sleeve,
results of studying the concerned delivery method and equipment wereconsolidated. “The method of delivering the whole unit” which is the same as themethod used for delivering the main access tunnel was selected, and the issues
and items that need to be verified by tests, etc. were consolidated.
➢ Based on the results consolidated as mentioned above, the specifications
pertaining to the remote sleeve installation equipment, sleeve structure, opening
part, installation procedures, etc. were studied using mock-ups. The actual
equipment (assumed) and the mock-up equipment were compared and the results
were compiled. Test plans including sensing were created, and a gap of 20mm orless (target 7.5mm or less) was established as the judgment criteria.
➢ Preparations were made for a full-scale test equipment and facility for remote
installation of the sleeve, and tests for verifying the feasibility related to theprocedures for remote installation of the sleeve and the equipment wereconducted.
➢ As a result of the tests, it was verified that the target of 7.5mm or less is met. Also,
issues in application to the actual equipment were identified and consolidated.

©International Research Institute for Nuclear Decommissioning7. Summary

No.672

1） Development of side access method(1) Development of the method of installing access equipment (Continued)② PCV connection sleeve remote installation and welding (continued)

Remote welding of the sleeve➢ The methods of responding to the issues pertaining to remote welding of thesleeve consolidated during the FY2019-20 subsidy project were studied in FY2021,
and issues as well as items that need to be verified through tests, etc. wereconsolidated.
➢ Items to be verified, monitored, measured and recorded were substantiatedthrough the welding, polishing and fluorescent PT (inspection) tests, andjudgment criteria were established.
➢ Preparations were made for element test equipment and facility for remote weldingof the sleeve, and element tests were conducted for verifying the feasibility related
to the procedures and equipment for remote welding of the sleeve.
➢ Feasibility of remote welding for a welding gap of 7.5mm or less was verified byconducting full-scale tests. However, there is a possibility that the welding
conditions for a welding gap of 7.5mm to 20mm will need to be revised. Also,
maintenance was studied to verify applicability to the actual equipment.
➢ Issues in application to the actual equipment were identified from the test results
and consolidated.

©International Research Institute for Nuclear Decommissioning7. Summary

No.673

1） Development of side access method(1) Development of the method of installing access equipment (Continued)③ Installation of shield➢ In FY2021, the study plan and the preconditions were consolidated and thereafter shielding
was evaluated, for studying the method for additional installation of shield. It was found that as
the radiation dose from neutron beams is high, neutron shielding needs to be installed toreduce the shielding thickness.
➢ Interference with the work of constructing the additional building is expected to be avoided(the access tunnel unit is expected to be pulled over with a crawler crane) by revising therequired shielding thickness from 300mm wall (iron) to 200mm (iron) (part of it added to thecart inside the access tunnel). The method for additional installation of shield continued to bestudied as additional shielding will be installed as required after ascertaining the status inside
the PCV.
➢ It was determined that feasibility of the proposal to additionally install spherical shields needs
to be verified through element tests. The items to be verified, and items to be monitored,measured and recorded during the filling test were studied, a filling rate of 60% was planned as
the criteria and the test was conducted.
➢ As a result of the element test, it was verified that the spherical shielding material can be filled
up to 20m ahead by using the blast equipment and the straight nozzle. Also, it was found thatfilling was possible up to a cell width of 500m, and that the structures inside the cell(reinforcement material) did not have an impact on filling.
➢ Since spherical shielding material can be filled up to 20m ahead, it was verified that theoperation can be performed from outside the R/B and thus worker exposure can be reduced.

©International Research Institute for Nuclear Decommissioning7. Summary

No.674

1） Development of side access method(1) Development of the method of installing access equipment (Continued)④ Disassembly of shield plug
➢ The course of study and preconditions pertaining to the method of disassembling
the shield plug in Unit 1 and concrete blocks in Units 2, 3 were consolidated in
FY2021, and the disassembly and removal procedures were studied briefly. The
disassembly procedures were consolidated. Issues in the methods were identified
and a rough exposure dose evaluation was carried out.
➢ The cranes and tools to be used were substantiated, and whether or not the items
to be processed such as concrete blocks, etc. can be processed was studied. The
necessity of the test including the study of smoothening methods was evaluated,
and the test plan was created (test items, verification contents and judgment
criteria were consolidated).
➢ Element tests were conducted based on the above-mentioned test plan, and it was
thus anticipated that it will be possible to remove concrete blocks in Unit 3 bycombining the methods tested this time (3 ton class crane + breaker). Also, issues
in application to the actual equipment were identified from the test results andconsolidated.

©International Research Institute for Nuclear Decommissioning7. Summary

No.6751） Development of side access method (Continued)(2) Development of disassembly and removal technology① HVH disassembly➢ In FY2021, results of studies conducted on HVH disassembly concerning theselection of items to be tested based on the pre-conditions and level of difficultyof disassembly, selection of circular saw and grindstone grinder as the cutting
technology, and identification of element test items based on the disassembly
work steps were compiled. The work steps were examined in detail, issues in eachof the steps were identified, an element test plan was created, and the test items,
judgment criteria, etc. were studied.
➢ Unit tests (tests conducted using the stand-alone equipment outside the simulated
environment) related to cutting were conducted, and the course of cutting was
substantiated through element tests.
➢ Element tests were conducted to verify the feasibility of the method ofdisassembling and removing the HVH, and the results were consolidated.
➢ Issues in application to actual equipment were identified, and the plan forreflecting them into the equipment design for the actual equipment wasconsolidated.

©International Research Institute for Nuclear DecommissioningNo.676

7. Summary1） Development of side access method (Continued)(2) Development of disassembly and removal technology (continued)② Disassembly of CRD exchanger➢ The pre-conditions pertaining to the disassembly of the CRD exchanger wereconsolidated, the method of disassembly and removal of CRD exchangers in Units
1/3 and the work steps involved were studied, and the test items were selected.
• Unit 2: The method of carrying out disassembly and removal by installing arail on the P/F, and moving the equipment to the specified locations inside
the pedestal by traveling over the rail.
• Units 1/3: The method of carrying out disassembly and removal byconstructing a scaffolding inside the pedestal using the P/F rotating rail
bracket on the inner wall of the pedestal, and moving the equipment to thespecified locations inside the pedestal by traveling over the scaffolding.
➢ The simulated facility, test pieces, equipment and tools used in the element tests
were test manufactured separately for the Unit 2 base and for the Units 1/3 bases,
the work steps were substantiated, and the element test plan was created.
➢ The feasibility of the method of disassembling and removing the CRD exchanger
was verified through element tests. Issues in application to the actual equipment
were identified and reflected into the equipment design for the actual equipment.

©International Research Institute for Nuclear Decommissioning7. Summary

No.6771） Development of side access method (Continued)(2) Development of disassembly and removal technology (continued)③ Interfering objects removal from pump pit➢ The status of fuel debris inside the pump pit, specifications of pump to be
removed, specifications of pump pit, and its location were studied andconsolidated in FY2021 as preconditions for removing interfering objects frominside the pump pit. The work steps involved in removing interfering objects frominside the pump pit were studied, and test items were selected.
➢ The simulated pump and pump pit, equipment and tools, etc. to be used in theelement tests were studied, the work steps were substantiated and the element
test plan (consolidation of items to be verified, test details, etc.) was created.
➢ It was verified through element tests that the pump can be cut, lifted up, etc. by
remote operation, and the feasibility of the method of removing interfering objects
from the pump pit was verified as well. Issues in application to the actual
equipment were identified and reflected into the equipment design for the actual
equipment.

©International Research Institute for Nuclear Decommissioning7. Summary

No.6781） Development of side access method (Continued)(3) Advancement and development of retrieval methods① Remote controlled tip tools for retrieval
Tip tools➢ Processing tests were conducted using tip tools that consider the specifications of accessequipment, and the importance of the prospects of application of the tip tools that had issues toactual equipment and the necessity to avoid collision during the grabbing action become evident.
Also, operators who had participated in the tests were made available. Also data for throughput
evaluation such as processing time, life of blades, etc. was refined.
➢ Throughput was evaluated using the above-mentioned data for throughput evaluation, and wasfurther refined.
➢ Requirements of the robot arm in terms of the processing reaction forces (blade pressing, blade
rotation) were obtained through processing tests.
➢ Measures were planned in response to the issues that became evident as a result of theprocessing tests.
Operation system➢ 4 operators, who had participated in tests, participated in the interfering objects removal mock-up
test using the operation system (trajectory planning) that has been developed. It was verified thata series of tasks were feasible in a confined environment such as the pedestal opening due to thecollision avoidance function of the operation system.
➢ The importance of position adjustment and the necessity of collision avoidance while performing
the grabbing action were clarified through the mock-up tests. And, the work items that theoperators took time to perform were verified as well.
➢ Items for further improving safety and efficiency of work in the future were selected from theissues identified through the mock-up tests conducted this time.
©International Research Institute for Nuclear Decommissioning7. Summary

No.6792) Development of top access method(1) Development of technology for realizing the concept of retrieving large structures① Method of cutting large structures➢ Pre-conditions pertaining to the method of transferring unitized large structures wereconsolidated, and overall steps were created.
➢ The methods for cutting the stud bolts of the RPV head from among the structures inside thereactor well were studied in FY2021, as a part of cutting “structures other than reactor internal
structures”, test pieces (RPV head, bolts) simulated to the actual equipment scale were
manufactured, and element tests on cutting the bolts with AWJ were conducted. The feasibilityof the method of cutting the RPV head bolts was verified, and issues were consolidated.
(Reported under “Accomplishment Report for FY2021*”)➢ In order to cut the reactor core after filling and solidification, methods of cutting the shroud
structures and the filler material were studied, as a part of cutting “reactor internal structures”.
The method of cutting the outer periphery of the shroud was developed on a priority basis inorder to proceed with cutting the inside (filled and solidified part) in parts after cutting theouter periphery of the shroud.
➢ The laser + pulse WJ cutting was selected as the method for cutting the outer periphery of the
shroud, element test plan was designed and the tests were conducted. Based on the results ofthe element tests, the feasibility of application of the method to cutting the outer periphery of
the shroud was verified, and issues were identified and consolidated in preparation for
designing the actual equipment.
➢ In addition to the characterization of geopolymer that is being considered as a filler material
carried out through injection tests using a barrel, tests were conducted to verify the impact of
exposure to radiation and issues were identified and consolidated in anticipation of applicationin actual equipment and scaling up. Also, work steps involved in filling and solidification wereorganized.
*Accomplishment Report for FY2021: https://irid.or.jp/wp-content/uploads/2022/08/2022007_deburitoridashi.pdf©International Research Institute for Nuclear Decommissioning7. Summary

No.6802） Development of top access method (Continued)(1) Development of technology for realizing the concept of retrieving large structures （Continued）② Large transfer containers➢ Pre-conditions pertaining to large transfer containers were consolidated in FY2021 and thedevelopment policy and method of using them were studied. Also, the aspects to be coveredby the simulation during the test were studied considering the structure of the large transfer
containers, their manufacturing procedure and the method of using them. Since the step of
opening and closing the container by moving the dual lid is important in terms of air-tightness
while using the large transfer containers, it was planned to verify air-tightness during the stepof opening and closing the container by moving the dual lid, by conducting element tests
using a container manufactured for the element tests.
➢ The structural designing of the actual large transfer container was carried out considering the
manufacturing capability and the method of using it.
➢ The feasibility of the large transfer container was verified by conducting element tests.
● As a result of the fitting test, it was verified that the equipment can fit as expected when theequipment is operated simulating the steps involved while operating the actual equipment, andthat the container can connect to the prescribed location following the equipment guide even if
there is some misalignment.
● As a result of the air-tightness test, it was verified that the rate of leakage at Part D (thesites sealed by sealed parts ③, ④, ⑤, ⑥) at the above-mentioned fitting position can meet thereference value.
➢ Issues in application to actual equipment were identified, and the items to be reflected into thecontainer specifications and equipment design of the actual equipment were consolidated.

©International Research Institute for Nuclear Decommissioning7. Summary

No.681

2） Development of top access method (Continued)(1) Development of technology for realizing the concept of retrieving large structures（Continued）③ Large transportation equipment➢ Pre-conditions pertaining to the structure of the large transfer equipment were put
together in FY2021 and the development policy was studied.
➢ The required functions of the large transportation equipment were studied andconsolidated. Also, potential drive systems for the shielding/transportation cartthat can be used in large transportation equipment were identified by investigating
existing technology/track records, further comparative evaluation was carried out
based on the required functions that have been consolidated, and the drive
system that was found to be promising in particular was studied.
➢ It was decided that element tests will be conducted focusing on the remoteconnector system in which power is supplied through the remote connector, and atest plan was created (test items, verification details, judgment criteria wereconsolidated).
➢ Element tests were conducted to verify feasibility. Issues in application to theactual equipment were identified and reflected into the equipment design for theactual equipment.

©International Research Institute for Nuclear Decommissioning8. Specific Goals for Achieving the Purpose of the Project and Evaluation of Level of Achievement
1) Development of side access method(1) Development of the method of
installing access equipment

No.682① Installation of large heavy structures[Objective]
The structure and installation method for installing the cell adapter,shielding door and cell that build the access route that is connected to the
PCV should be detailed, and its feasibility should be shown throughelement tests.
(Target TRL at completion: Level 4)[Evaluation of level of achievement]
The structure and installation method for installing the cell adapter,shielding door and cell that build the access route that is connected to the
PCV were detailed, and its feasibility verified through element tests. (TRL:
Level 4)
② PCV connection sleeve remote installation and welding[Objective]
The method of remotely installing the access tunnel sleeve connected to
the PCV should be studied, the requirements should be consolidated, andfeasibility should be shown through element tests. Also, feasibility of themethod of welding by remote operation should be shown through element
tests.
(Target TRL at completion: Level 4)[Evaluation of level of achievement]
The method of remotely installing the access tunnel sleeve connected to
the PCV was studied, the requirements were consolidated, and feasibility
was verified through element tests. Also, feasibility of the method of
welding by remote operation was verified through element tests.
(TRL: Level 4)©International Research Institute for Nuclear Decommissioning8. Specific Goals for Achieving the Purpose of the Project and Evaluation of Level of Achievement

No.683③ Installation of shield[Objective]
Feasibility such as manufacturing capability, etc. of the access tunnel shieldshould be shown through element tests.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
The feasibility of the method of installation of additional access tunnel shielding
was verified element tests. (TRL: Level 3)④ Disassembly of shield plug
[Objective]
Feasibility of the cutting/disassembly methods with regards to the method of
removing the shield plug, etc. (shield plug, blockout) located in front of theequipment hatch when the side access method is used, should be shown throughelement tests.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
Feasibility of the cutting/disassembly methods with regards to the method of
removing the shield plug, etc. (concrete block) located in front of the equipment
hatch was verified through element tests.
(TRL: Level 3)(2) Development of disassembly and removal ① HVH disassembly
technology[Objective]
Feasibility of specific cutting/collection methods with regards to the method of
removing HVH, which are large systems among the equipment installed outside
the pedestal, should be shown through element tests.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
Feasibility of specific cutting/collection methods with regards to the method of
removing the HVH exchanger was verified through element tests. (TRL: Level 3)1) Development of side access method(Continued)(1) Development of the method of installing
access equipment (Continued)©International Research Institute for Nuclear Decommissioning8. Specific Goals for Achieving the Purpose of the Project and Evaluation of Level of Achievement
1） Development of side access method (Continued)(2) Development of disassembly and removal
technology (continued)(3) Advancement and development of retrieval
methods

No.684② Disassembly of CRD exchanger[Objective]
Feasibility of specific cutting/collection methods with regards to the method of
removing the CRD exchanger, which is a large structure located at the center of thepedestal, should be shown through element tests.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
Feasibility of specific cutting/collection methods with regards to the method of
removing the CRD exchanger was verified through element tests. (TRL: Level 3)③ Interfering objects removal from pump pit[Objective]
Feasibility of the method of cutting, etc. and transferring with regards to the method of
removing interfering objects from inside the pump pit, which is required for installing thesubmersible pump into the pump pit inside the PCV, should be shown through element
tests.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
Feasibility of the method of cutting, etc. and transferring with regards to the method of
removing interfering objects from inside the pump pit was verified through element tests.
(TRL: Level 3)① Remote controlled tip tools for retrieval[Objective]
The viability of a series of operations from processing interfering objects and fueldebris from inside the PCV to collecting the cut pieces in unit cans should be shown
through element tests, etc., and data for evaluating the throughout should be acquired.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
The viability of a series of operations from processing interfering objects and fuel debris
from inside the PCV to collecting the cut pieces in unit cans was verified through element
tests, etc., and data for evaluating the throughout was acquired. (TRL: Level 3)©International Research Institute for Nuclear Decommissioning8. Specific Goals for Achieving the Purpose of the Project and Evaluation of Level of Achievement
2) Development of top access method(1) Development of technology for realizing
the concept of retrieving large structures

No.685① Method of cutting large structures[Objective]
Feasibility of the cutting and separating with regards to the method of cutting
structures when the top access method is used, should be shown throughelement tests. Also, the method of transferring structures after they have been cut
until the structures are loaded on to the large transportation equipment, should bestudied, and its site applicability should be evaluated.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
Element tests related to cutting the RPV head bolt and cutting the outer
periphery of the shroud with regards to the method of cutting structures when the
top access method is used, were conducted, and the feasibility was verified. Also,
the overall steps including the steps from removing the structures to transferring
them were created, and issues were identified. (TRL: Level 3)② Large transfer containers[Objective]
The performance of the container in which unitized structures are stored andtransferred when the top access method is used, should be verified throughelement tests, and the issues in site applicability should be indicated.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
Element tests were conducted related to air-tightness of the container forstoring the unitized structures and transferring them (large transfer container)when the top access method is used, the feasibility including the manufacturing
capability was verified, and issues in application to the actual equipment wereidentified. (TRL: Level 3)©International Research Institute for Nuclear Decommissioning8. Specific Goals for Achieving the Purpose of the Project and Evaluation of Level of Achievement
2) Development of top access method(Continued)(1) Development of technology for realizing
the concept of retrieving large structures(Continued)

No.686③ Large transportation equipment[Objective]
The site applicability of the large transfer equipment including its drive
mechanism, which is used for transferring structures retrieved by means of the
top access method within the R/B should be verified through element tests, andthe issues should be consolidated.
(Target TRL at completion: Level 3)[Evaluation of level of achievement]
The feasibility of large transfer equipment including its drive mechanism astransportation equipment was verified, and issues were identified. (TRL: Level 3)

TRL level

Explanation

Phase

TRL7

Stage at which implementation is complete.

For practical use

TRL6

Stage at which field verification is conducted.

Field verification

TRL5

Stage at which a prototype is manufactured based on the actual equipment and verified in a simulated
environment at the factory, etc.

Simulated verification

TRL4

Stage at which functional tests are implemented at the test manufacturing level as a development andengineering process.

Research for practical use

TRL3

Stage at which development and engineering are being carried out by applying or combining pastexperiences. Or, stage at which development and engineering are being carried out based on
fundamental data in domains in which there is no prior experience.

Applied research

TRL2

Stage at which development and engineering are being carried out in domains in which there is almost no
applicable prior experience, and the required specifications are being defined.

Applied research

TRL1

Stage at which specific details pertaining to the development and engineering targets are clarified.

Basic research©International Research Institute for Nuclear DecommissioningNo.687

Explanation of terminology (1/2)
No.

Term

Explanation

1

1F

Fukushima Daiichi Nuclear Power Plant

2

R/B

Reactor Building

3

Rw/B

Radioactive waste treatment building

4

T/B

Turbine Building

5

PCV

Primary Containment Vessel

6

RPV

Reactor Pressure Vessel

7

CRD

Control rod drive mechanism

8

Refueling floor

Refueling floor

9X-6 penetration

One of the PCV penetration parts

10

S/C

Suppression chamber

11

Cell adapter

The piece that connects the PCV and the cell

12

BSW

Biological shielding wall

13

MCCI

Molten Core - Concrete Interaction

14

UC

Unit can (Container in which fuel debris is placed)

15

AWJ

Abrasive Water Jet

16

HVH

Heating Ventilating Handling Unit

17

CRGT

Control Rod Guide Tube

18

G/H

Greenhouse

19

LLW

Low level radioactive waste

20

MSM

Master - Slave Manipulator
Note: Since the term master-slave contains discriminatory words, its use is generally avoided, but as the term has been
established as an academic term in robotics since a long time, it is being used as is as a term.
While using the term in the future, we will refer to the trend of related societies such as The Robotics Society ofJapan, etc.

©International Research Institute for Nuclear DecommissioningNo.688

Explanation of terminology (2/2)
No.

Term

Explanation

21

CW

Counter weight

22

AVC

Arc voltage adjustment function (Function of correcting the arc length by controlling the voltage fluctuations between
the welding torch and the base material to keep them within a certain range)

23

OSC

Function of controlling the shaking of the welding torch

24

P/F

Platform

25

TIP

Traversing In Core Probe System

26

CID

Charge Injection Device

27

MS

Main steam

28

DSP

Dryer Separator Pit

29

FWS/CS

Feed Water System / Core Spray System

30

ICM

In-core nuclear instrumentation©International Research Institute for Nuclear Decommissioning