Subsidy Project of Decommissioning and Contaminated Water Management
Started from FY2021

Development of Fuel Debris Retrieval Method
Accomplishment Report for FY2021

August 2022
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 the side access method
2) Development of the top access method
7. Summary
8. Specific goals for achieving the purpose of the project
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 assumed that the nuclear fuel has melted along with the reactor internal structures at Tokyo Electric Power Company Holdings, Inc. (TEPCO) Fukushima

Daiichi Nuclear Power Station (NPS) 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, in this project studies will be conducted based on the “Mid-and-long-term Road-map Towards Decommissioning of TEPCO’s
Fukushima Daiichi Nuclear Power Station” (hereinafter “Mid-and-Long-Term Road-map”), aiming towards the implementation of large-scale fuel debris retrieval
in coordination with the engineering and project management activities undertaken by TEPCO. The development results of this project will be used in TEPCO’s
engineering activities.
The purpose of this project is to appropriately carry out decommissioning and contaminated water management at the Fukushima Daiichi NPS by
implementing projects that support technological development contributing to the decommissioning and contaminated water management at the Fukushima
Daiichi NPS based on the Mid-and-Long-Term Road-map and the “FY2020 Research & Development Plan” (Secretariat of the Team for Countermeasures for
Decommissioning and Contaminated Water Treatment (75th session)), and in addition, to enhance the standard of science and technology in Japan.
Under the project for “Development of Fuel Debris Retrieval Method”, the necessary elemental technologies will be developed and tested based on researchand development results obtained so far on the technologies related to devices, equipment and systems required for increasing the retrieval scale of fuel debris
and reactor internal structures and on securing retrieval work area for ensuring throughput.

[Project goal]
The goal of the project is to conduct study in order to accomplish large scale fuel debris retrieval inaccordance with 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 tunnel

The distal end of the rail is raised
due to the inclination, and hence
vertical space is required.

Robot arm

Interfering
objects

Welding
robot

Line of flow of the robot
arm and unit can
Height is reduced by keeping
the rail inside the cellhorizontally

Welding head

Unit canAccess rail

Fixed rail Robot arm

Welding
robot
Frame

Simulated equipment
hatch part

Transportation
cart

Frame

Result: Development of access tunnel
installation (welding) technology

Dual arm typemanipulator
Result: Development oftechniques for supporting remote
operations

Line of flow of the robot
arm and unit can

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

Interference
removalequipment

CRD
opening(5) Top access method
Interfering
objects

Retrieval equipment

PassagewayInterfering
objects
Processing
tool

Secondary boundary

Additional building

Connection
sleeveDual lid
Transport
ation cart

Dedicated transport
container

Processing
tool

Result: Method for interference removal using fuel debris
retrieval equipment when side access method is applied.
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 cells]•••

A boundary formation is ensured by cells and fuel debris is
retrieved by 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.

transportation
Mini cask cell cask cell
Canister cell

Fuel debris
retrieval cell

Fuel debris retrieval
preparatory cell
Dual arm type robot
containertransportation
cask yard[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 installed 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 and installation method•
The illustration showing the steps that are expected to be viable frompreparatory work to installation and installation was studied and technicalissues were identified.

Fuel debris transportation
cask cell

Access equipment
Temporarystorage 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

No.5

2. Accomplishments of Related Projects Implemented in FY2019-20(1) Establishment of access route for installation of cells◼

Issues in cell installation: Items related to this project are excerpted from the Fuel Debris Retrieval FY2020 Final Report *1
No.

Issue

Overview

This project1

Detailing of the structure of theshielding door and the structure
between cells

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 the cells
will be detailed.

Refer to 6.1) (1) ①

2

Substantiation of the cell adapter
structure

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

Refer to 6.1) (1) ①

3

Substantiation of t h e m e t h o d o fcarrying-in and installing the shielding
door and the cell adapter

The steps involved in carrying-in, 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 byremote operation will be planned and implemented; and feasibility
will be verified.

Refer to 6.1) (1) ①

4

Establishment of the reference
marking method for cell installation

The method of measurement and marking performed in advancefor 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 connectedwith an access tunnel having a shielding function, to establish thecarrying-in/out route.
The load of the access tunnel is 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 andinstalled by remote operation so as to reduce worker exposure.

•

PCV
Access tunnel
アクセストンネル[Items implemented until FY2020]•

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)✓ Stacking method✓ Welding position✓ Heat input for welding✓ Welding gap
Flat plate(t=90)

No.6

Illustration of access tunnel

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

Implemented

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.

IssuesOverview

This project1

Installation accuracy of access tunnel
sleeve

The access tunnel sleeve is welded to the PCV equipment
hatch shell. Although it was confirmed that the 20mm gap canbe welded, the gap needs to be reduced as much as possible
considering the on-site workability, thermal contraction effectat the time of welding, and quality.

Refer to 6.1) (1) ②

2Re ducti on in the sca le of del ive r yequipment by reducing the delivery weightof the main body of the access tunnel andshortening of the installation process

The delivery weight of the main body of the access tunnel isapprox. 430 ton, and exceeds 1000 ton if the counterweight isincluded. 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 theR/B such as constructing the additional building, etc.

Refer to 6.1) (1) ③

3Shield block (Unit 1) and BSW block out(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2. Accomplishments of Related Projects Implemented in FY2019-20(3) Side access method using access tunnel

搬入セル
Carrying-in
cell

Waste
廃棄物
搬出セル
transfer cell

燃料デブリ
Fuel
debris
取り出しセルretrieval cell[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 interfering objects from inside PCV and the workof fuel 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 theinterfering object is inside or outside the pedestal.

✓✓

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ユーティリティラインとPCV内でのof the cables of the work
作業装置のケーブルを接続
equipment inside
the PCV to the utility line
Equipment
機器ハッチ
hatch

Utilityline: Installed by
ユーティリティライン：remote operation
遠隔にて構築Simulated
ICM
housingIllustration showing installation ofutility line

PCV

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

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

1. Carrying-in the①干渉物撤去interference
removal
装置搬入
equipment
2. Removal of interfering②CRD開口周辺
objects from around the
干渉物撤去
CRD opening

5. Transfer of⑤干渉物の搬出interfering objects

Illustration showing removal of interfering
CRD開口周辺干渉物撤去イメージ
objects from around the 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 objects from
④ペデスタル底部干渉物撤去
the pedestal bottom

Saber saw
Monitoring
監視装置
equipment

保守セル
Maintenancecell

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

No.8

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.

IssuesOverview

This project1

Method of removing large
interfering objects

The method of removing large interfering objects such as CRD
exchanger, 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 typedual motor-operated arms

[Items implemented until FY2020]
•

•
•

•

•

The following conceptual studies on the access equipment for accessing the interfering
objects and fuel debris 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
motor-operated 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 the pedestal CRD opening.
The procedures for removing the interfering objects and retrieving fuel debris were brushed
up and substantiated, technical issues were identified and the actions to be taken in response
were studied.
Methods supporting remote operation were studied for better work efficiency.

Fixed rail type hydraulic arms

Trajectory for avoiding simulated interfering objects
and reaching the target value
Trajectory of right arm
Trajectory of left arm

Generation of trajectorywhen 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.

IssuesOverview

This project1

Conceptual study of tip
tool

The method for cutting the assumed interfering objects and fuel debris and theconcept of the tip tool need to be studied although under certain preconditions to get an idea of the overall work including throughput.

Refer to 6.1) (3) ①

2

Dealing with deviation

Deviation during remote operation support by the manipulator, caused due tothe difference in the 3D model and the actual objects on-site, and due toerrors in installation 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： “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]
✓

✓

✓

原子炉建屋
The retrieval plan and removal method pertaining to Reactor
Building (R/B)
interfering objects, from removing the shield plug up to thereactor bottom, were consolidated and a draft of the steps
揚重機
Crane
involved in the access method was created.
連絡通路
Passageway
It was indicated that measures to reduce the weight of theshielding on the operation floor, the crane and the means of
Heavy weight on
オペフロ上
the operationtransportation are feasible, and the specifications such as
floor
重量大
dimensions, shield weight, etc. of the large transportation
Connection
接続
containers were created.
sleeveスリーブ
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 thethroughput estimation.

Retrievalequipment
取り出し装置Transportation
搬送
cart
台車

Additional
増設建屋 building

二重蓋
Dual
lid
Dedicated transportation
輸送専用容器
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.

IssuesOverview

This project1

Method for cutting
structures other than thereactor bottom

During the conceptual study, cutting the shroud into upper and lower parts wasconsidered as a work step. The method of cutting the reactor internal structures
including the shroud will be re-examined and studies will be conducted on
substantiation of the cutting method.

Refer to 6.2) (1) ①

2

Substantiation of the largetransfer container

Conceptual studies were conducted on large transfer containers (dedicatedtransportation containers) for transferring structures up to the new building. In the
future, the structure of large transfer containers will be substantiated, and studies will
be conducted on the structural viability including manufacturing capability, etc.

Refer to 6.2) (1) ②

Substantiation oftransportation equipment

Cutting structures that cannot be directly stored in large containers in the additionalbuilding was considered as a work step in the conceptual study. Also, localizedshielding will be added for structures that have a high radiation dose rate. Hence,
substantiation of the means for transporting the retrieved structures will be studied,and revision of the work steps will be considered in accordance with the workability
at the additional building.

Refer to 6.2) (1) ③

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 ofContamination while Retrieving and Transporting Large Structures

Continuous
monitoring
Development of System
for Continuous Monitoring Inside the PCV

Sharing of investigation needs/results

Internal
Investigation

Sharing of technicalchallenges

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

Development of Safety System
Development of Liquid/Gas Phase Systems,
Criticality Control Technology
Sharing thestatus of studies

Sharing of analysis needs/results

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 RPVDevelopment 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 safety
scenarios・Coordination ofwork steps

Sharing oftechnical challenges

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

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

Solid Waste
Research and Development for
Treatment and Disposal of Solid Radioactive Waste

In this project, joint meetings have been conducted as required in coordination with the above-mentioned projects.
©International Research Institute for Nuclear Decommissioning3. Project overview

No.15

3. 2 Development items involving solicitation and implementation policy

2) Top access method2)(1)③: Large transportation equipment

1) Side access method
1)(2)②: Disassembly of CRD exchanger1)(2)①: HVH disassembly1)(2)③: Interfering objects removal frompump pit1)(1)①: Installation of large heavy structures2)(1)①: Method for cutting
large structures2)(1)②: Large transfer container1)(3)①: Remote operation tip tool for retrieval1)(1)②: PCV connection sleeve installation and welding
by remote operation1)(1)③: Installation of shield1)(1)④: Disassembly of shield plug

©International Research Institute for Nuclear Decommissioning3. Project overview

No.16

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

Implementation policy

Reference

1) Development of the side
access method(1) Development of themethod of installing accessequipment① Installation of large heavy structures
The pre-conditions and required specifications will be clearly specified, the cell structure installed inside R/B
and the structure of the access equipment will be detailed, the installation method will be studied, and thefeasibility 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 pieces, etc.

No. 26 to 86② 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 beconsolidated, the method of installation by remote operation, the devices and equipment, and procedures 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 to welding, inspection and maintenance ofthe sleeve, etc. as containment technology for the connecting 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. 87 to 122③ Installation of shield
In order to reduce the floor load of the ancillary facilities required for transportation to the inside of the R/B, theR/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. 123 to 140④ Disassembly of shield plug
As the shield plug, etc. (shield plug, block out) in front of the existing equipment hatch, which is a large andheavy object made of concrete, etc. needs to be removed, technology related to safe and efficient disassemblyin confined spaces will be studied and developed.

No. 141 to 161① 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 equipment developed so far using
simulated test pieces will be planned and implemented considering remote operation in limited space, and thefeasibility of specific cutting/collection methods will be verified.

No. 162 to 202② 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. 203 to 253(2) Development ofdisassembly and removal
technology©International Research Institute for Nuclear Decommissioning3. Project overview

No.17

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

Implementation policy

Reference

1) Development of the side
access method(2) Development ofdisassembly and removal
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 with tools, etc.
Hence, the method of confirming the status of the target objects by means of images captured by the camera,
and then cutting, etc. and transporting will be studied in detail, and feasibility will be verified by element tests.

No. 254 to 276(3) Advancement anddevelopment 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 andconducting element tests, etc., and the viability of the series of operations will be verified. Also, the actual dataon the work procedures will be acquired and consolidated, and data for evaluating the throughput will beobtained.

No. 277 to 331

2) Development of the top
access method(1) Development oftechnology for realizing
the concept of retrieving
large structures① Method for 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, the method oftransferring cut structures including PCV head, etc. until the structures are loaded on to the large transfer
equipment, will be studied, and on-site applicability will be evaluated.

No. 332 to 379② Large transfer container
Detailed study will be conducted on the conceptual structure of the transfer system including the method ofplacing the structures in the large transfer container, the air-tightness and shield structure of the large transfer
container as a whole including the lid part, manufacturing procedures, etc. Also, the structure of the largetransfer container will have to be such that it is easy to decontaminate the inside of the container assuming it
will be re-used. Furthermore, full-scale transfer containers will be test manufactured, their peformance will beverified by element tests, viability will be verified and issues in on-site application will be identified.

No. 380 to 404③ Large transportation equipment
The preconditions of the large transportation equipment and the required development items will be studied andconsolidated, the method for transporting large heavy contaminated structures with certainty will be investigatedand studied in terms of the adaptability to the air-tight gate, etc., on-site applicability of the large transportationequipment will be evaluated by element tests and structural examination of the transportation equipment
including the drive mechanism, and issues will be identified.

No. 405 to 423©International Research Institute for Nuclear Decommissioning3. Project overview

No.18

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 handlingcapability and maintenance methods of the equipment that will be handled remotely, interms 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 to betaken into consideration.

・Work area will be limited 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 be considered.

©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）

4. Implementation schedule of this project【凡例】[Legend]：計画
Planned：見直し
RevisedActual：実績

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

2021年度 FY2021
2022年度 2022年度
FY2022
2021年度Small
備考
小分類
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
classification
Apr May
Jul Aug
Oct 11月
Nov 12月
Dec 1月Jan Feb
4月
5月 Jun
6月 7月
8月 Sept
9月 10月2月 Mar
3月 Apr
4月 May5月 Jun
6月 9月
7月
8月11月
9月12月
10月
11月
12月
1月 Feb
2月 Mar
3月
Jul 10月
Aug
Oct 1月Nov 2月Dec 3月
Jan
Sept

No.19
備考
Remarks

り出し工法の開発
横取り出し工法の開発
1.１. Developmentofstudy of the structure of accessequipment
アクセス用設備の構造詳細検討
セス用設備の設置工
Detailedstudy of the Detailed
概念検討(１) アクセス用設備の設置工 a. a.
アクセス用設備のside
accessmethod開発
a. 概念検討 structureof access法の開発
構造詳細検討equipment
重量構造物の開発(1)
Development of① 大型重量構造物の設置
要素試験計画
b. Detailing and study
アクセス用設備の据付ステップ詳細化検討
Detailingand study of the steps for installing access equipmentb. 要素試験計画
b. アクセス用設備のmethod for installing
of

the

steps

for

据付ステップ詳
installing
accessaccess equipmentc. 試験準備/ equipment
細化検討① Installation of試験装置試作
c. Verification of thelarge heavy
installationc.
据付手順の要素
d. 要素試験 procedures
structures
試験検証 throughe. まとめ接続スリーブ遠隔設
溶接

element tests
d. Detailing of the workd.
燃料デブリ取り出
insidethe cell of the
fuelし設備のセル内
debris retrieval
equipment
作業の詳細化e. Report creation

まとめ Report
creation
報告書作成

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

概念検討

a. 概念検討 e. 報告書作成
要素試験計画

b. 要素試験計画
a.Conceptualc. 試験準備/ a.study
概念検討
b.Element
test
試験装置試作②②Remote
installation
ＰＣＶ 接続スリーブ遠隔設
planb. 要素試験計画
and置・溶接
welding of PCV
d. 要素試験 c.Test preparation/ testconnection sleevec.manufacturing
試験準備/
e. まとめof試験装置試作
test

体設置

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
要素試験

equipmentd. 要素試験
d.Element
tests
e.Summarya. 概念検討 e. まとめ

Conceptual
study
概念検討

試験準備/試験装置試作

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

まとめ

Element
tests
要素試験

概念検討

Summary
まとめ

要素試験計画

b. 要素試験計画

a.Conceptualc. 試験準備/ a.
study
概念検討
試験装置試作b.Element test
③ 遮蔽体設置③
Shield installation
planb.
要素試験計画
d. 要素試験 c.Test preparation/ Testc.
試験準備/
e. まとめmanufacturing
試験装置試作of testequipmentd.
要素試験
d.Element test
e.Summarye. まとめConceptual
概念検討 study

試験準備/試験装置試作

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

まとめ

Element
要素試験
tests
Summary
まとめ©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）

4. Implementation schedule of this project【凡例】[Legend]：計画
Planned：見直し
RevisedActual：実績

Development of fuel debris
retrieval method 実施スケジュール（2/4）
Implementation Schedule (2/4)
燃料デブリ取り出し工法の開発
大分類
小分類
大分類
Large classification

2021年度 FY2021
2022年度 2022年度
FY2022
2021年度Small
備考
小分類
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
classification
Apr May
Jul Aug
Oct 11月
Nov 12月
Dec 1月Jan 2月Feb 3月Mar 4月
4月
5月 Jun
6月 7月
8月 Sept
9月 10月5月 Jun
6月 9月
7月
8月11月
9月12月
10月
11月
12月
1月
Apr May
Jul 10月
Aug
Oct 1月Nov 2月Dec 3月Jan 2月Feb 3月Mar
Sept

り出し工法の開発
横取り出し工法の開発
1.１.Developmentof
セス用設備の設置工(１) アクセス用設備の設置工 a. Conceptual study
side
accessmethod開発
a. 概念検討 a. 概念検討
法の開発
重量構造物の開発
b. Element test plan(1)
Development of④ シールドプラグの解体
b. 要素試験計画
b. 要素試験計画

概念検討

備考
Remarks

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

要素試験計画

method for installing c. Test preparation /access equipmentc. 試験準備/ c. 試験準備/
test manufacturing④ Disassembly 試験装置試作
of
試験装置試作shield plugof test equipment

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
要素試験

d. 要素試験 d. 要素試験

Elementtests
要素試験

d. Element tests

e. まとめ

No.20

まとめ
まとめ Summarye. まとめe. Summary(2)
Development of(２) 解体・撤去技術の開発
Conceptual study
a. 概念検討 a. a.
disassembly and
概念検討
接続スリーブ遠隔設①
HVH解体
b. Element test plan
removal technology
溶接b. 要素試験計画 要素試験計画① HVH disassembly c.b.
Test preparation /c. 試験準備/ c. 試験準備/
test manufacturing
試験装置試作試験装置試作概念検討

Element
test plan
要素試験計画要素試験計画
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
要素試験

of test equipmentd. 要素試験 d. 要素試験
e. まとめ•As
the 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,
実施場所が同一のた
removalofinterferences
from
め、実施時期を見直theし。 pump pit are
conducted at thesame location, thetime ofimplementation will
be revised.

Conceptual
study
概念検討

Elementtests
要素試験

d. Element tests

まとめe. まとめSummaryまとめe. Summarya. Conceptual study

a. 概念検討 a. 概念検討
b. Element test plan
体設置
② Disassembly
CRD交換機の解体of②
b. 要素試験計画
要素試験計画c.b.
Test
preparation /CRD exchangerc. 試験準備/ c.
test試験準備/
manufacturing
試験装置試作 試験装置試作
of test equipmentd. 要素試験 d. 要素試験
d. Element tests
e. まとめ

要素試験計画Element
test
plan
要素試験計画

Test preparation /試験準備/試験装置試作
test
manufacturing of test equipment
試験準備/試験装置試作
Basic
tests related to fall prevention
落下防止・切断片搬出
andtransferring the cut pieces
に関する基礎試験

Element
要素試験 tests要素試験
まとめ

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

概念検討 Conceptual
概念検討 study

Summary
まとめ©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）

4. Implementation schedule of this project[Legend]【凡例】：計画
Planned
Revised：見直し
Actual：実績

Development of fuel debris 燃料デブリ取り出し工法の開発
retrieval method
Implementation
Schedule (3/4)
実施スケジュール（3/4）

2021年度
2022年度
Small
2021年度 FY2021
2022年度 FY2022
Large classification
大分類
小分類
大分類
小分類 classification
備考
Apr
May
Jun
Jul Aug
Oct 11月
Nov 12月
Dec 1月Jan 2月Feb Mar
Sept
Apr
May
Jun
Jul
Aug
Oct 1月Nov 2月Dec 3月Jan 2月Feb 3月
Mar
Sept
4月
5月
6月
7月
8月
9月
10月
3月
4月
5月
6月
7月
8月
9月12月
10月
11月
12月
1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 10月 11月

横取り出し工法の開発
り出し工法の開発
1.１. Developmentof(２) 解体・撤去技術の開発
study
セス用設備の設置工
side access method a.a.Conceptual
概念検討
開発
a. 概念検討(2)
Development of
b. Element test plan
③ ポンプピット内干渉物撤去
重量構造物の開発
b. 要素試験計画
disassembly andb. 要素試験計画

概念検討 study
Conceptual

概念検討

Element
test plan
要素試験計画要素試験計画

試験準備/試験装置試作

Element
tests
要素試験
要素試験

d. Element tests

e. まとめe. まとめa.Study ofc. 要素試験（スc.Element
test
試験装置試作
ループット評価用(Processing
test
加工試験）
d. 要素試験 for evaluating
throughput)d. 操作システムのd.Studyofe. まとめ検討 system
operatinge.Development ande. 操作システムのsimulation
開発・シミュレー
verificationofa. 概念検討
ション検証
operatingsystemf. Element testb. 要素試験計画(Seriesoff. 要素試験（操作
operations
using
システムを使った
c. 試験準備/the一連作業）
operating
試験装置試作
system)g.Report
creationg. 報告書作成
d. 要素試験

e. まとめまとめ

e. Summary(３) Advancement
取り出し工法の高度化開
a. スループット改善
to(3)
and measures
発策の検討
enhancea.
概念検討
developmentof① 取り出し用遠隔先端ツー
throughput
接続スリーブ遠隔設
retrievalmethodルb. 先端ツール要素
b.Tip
tool element
溶接b. 要素試験計画① Remotely operated test試験計画・準備
plan andtip tool for retrievalc. 試験準備/ preparation

体設置

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

c. Test preparation /removal technology
c. 試験準備/manufacturing③ Removal ofc. 試験準備/ test試験装置試作
試験装置試作
interfering objectsof test equipmentfrom the pump
pit
d.
要素試験
d. 要素試験

No.21

備考Remarks•As
the 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,
実施場所が同一のた
removalofinterferences
from
め、実施時期を見直theし。 pump pit are
conducted at thesame location, thetime ofimplementation will
be revised.

Summaryまとめ

Studyof measures to enhance throughput
スループット改善策の検討
概念検討
Tip
tool element test plan and preparation
先端ツール要素試験計画・準備
要素試験計画Element test
要素試験 test for(Processing
evaluating
throughput)（スループット評価用加工試験）

試験準備/試験装置試作

要素試験

Study
of operating system
操作システムの検討
まとめ

Development
and simulation verification of operating system
操作システムの開発・シミュレーション検証
概念検討
要素試験計画Element test
要素試験（操作システムを使った一連作業）(Seriesof operations using the operating system)
試験準備/試験装置試作

Reportcreation
報告書作成
要素試験
まとめ

©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）

4. Implementation schedule of this project【凡例】[Legend]：計画
Planned：見直し
RevisedActual：実績

燃料デブリ取り出し工法の開発
実施スケジュール（4/4）
Development of fuel debris
retrieval method
Implementation Schedule (4/4)

2021年度FY2022
Small
2021年度 FY2021
2022年度 2022年度
大分類
小分類
Large classification
大分類
小分類 classification
備考
4月
5月 8月
6月 9月
7月
8月11月
9月12月
10月
11月
12月
1月
2月
3月
4月
5月 8月
6月 9月
7月
8月11月
9月12月
10月
11月
12月
1月
3月
Apr 7月May
Jun
Jul 10月
Aug
Oct 1月Nov 2月Dec 3月Jan 4月Feb 5月Mar 6月Apr 7月May
Jun
Jul 10月
Aug
Oct 1月Nov 2月Dec 3月Jan 2月Feb Mar
Sept
Sept
4月 5月 6月

上取り出し工法の開発
り出し工法の開発
2.２.Developmentof top(１) 大型構造物の取り出しコ a. Conceptual study
セス用設備の設置工
access method
ンセプト 実現に向けた技
a. 概念検討開発
a. 概念検討b. Element
test plan(1) 術開発
Developmentof
重量構造物の開発
technology
forb. 要素試験計画① 大型切断工法
要素試験計画c. b.
Test
preparation /realizing the conceptc. 試験準備/manufacturingc. 試験準備/ testof retrieving large
試験装置試作試験装置試作
structuresof test equipment① Method of cuttingd.
要素試験
d. 要素試験d. Element
tests
large structurese. まとめ

概念検討

要素試験計画Element
test plan
要素試験計画

Test preparation /試験準備/試験装置試作
test
manufacturing of test equipment
試験準備/試験装置試作
Element tests
要素試験（RPVヘッド解体）(RPV
head disassembly)

e. まとめe. Summarya. Conceptual study

a. 概念検討 a. 概念検討
b. Element test plan
接続スリーブ遠隔設②Large
大型搬出容器b. 要素試験計画
transfer
溶接 ②
b. 要素試験計画

c. Test preparation /container

Conceptual
概念検討 study

試験準備/
c. 試験準備/ c.
test manufacturing
試験装置試作 試験装置試作•As the time of the・RPVヘッドスタッドボ
RPV head stud
ルト切断要素試験に
bolt cutting
ついて、他試験と試験
element test
時期が重複するため、
overlaps with thetest time of other2021年度中に要素試
tests, element test
験を実施することで試
will be conducted験準備を実施し、要素
in FY2021, andthus test
試験を実施。
Element tests
preparations will
要素試験（炉内構造物切断）(Cutting
reactor internal structures)be made and
要素試験
element tests will
be conducted.
Summary
まとめ
まとめ

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

of test equipment

Element
要素試験tests

要素試験

d. Element tests

e. まとめまとめ

e. Summarya. Conceptual study

a. 概念検討 a. 概念検討
b. Element test plan
体設置③
大型搬送装置b. 要素試験計画
b. 要素試験計画③ Large transfer

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

c. Test preparation /containersc. 試験準備/c. 試験準備/ test
manufacturing
試験装置試作 試験装置試作

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

of test equipment

Element
tests
要素試験
要素試験

d. 要素試験 d. 要素試験

d. Element tests

e. まとめまとめe. まとめe. Summary

主要なマイルストン
Major
milestones

備考
Remarks

Conceptual
study
概念検討
概念検討

d. 要素試験 d. 要素試験
e. まとめNo.22

Summary
まとめ・作業容器や隔離•Afterorganizing the
シートを含めた搬出入
issuesbased on thesteps
for carrying in/out
ステップに基づく課題
the work container and
整理後に要素試験項
isolation
sheet, element
test
items are planned
目の抽出等を行い要
tobe identified, etc. and素試験計画を立案予
element test plan is
定。
plannedto be created.
•As
studying the steps
・搬出入ステップ検討
for carrying on/out andおよび課題整理に時organizing
the issues
requirestime, the test
間を要していることかplan
isplannedto be
ら、試験計画の立案はcreated from FY2022
2022年度から実施予
onwards.
定。

中間報告InterimreportAnnualreport
年度末報告

Interimreport中間報告

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

No.23

International Research Institute for Nuclear Decommissioning(IRID)

Tokyo Electric Power Company (TEPCO) Holdings,
Inc.
➢ Various coordination for site application➢ Coordination of overall planning and technology management➢ Coordination of technology administration including technology
development progress management

Project teams to cooperate fortechnological development
Development
MethodHitachi-GE Nuclear Energy, Ltd.
[Element tests, technical development]
1) Development of the side access method(1) Development of the method of installing accessequipment② PCV connection sleeve installation and welding
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

of

Fuel

DebrisRetrieval(Development of Isolation Technology for
Preventing Spread of Contamination while
Retrieving and Transporting Large Structures)

Mitsubishi Heavy Industries, Ltd.
[Element test, technical development]
1) Development of the side access method

Development of technology for further
increasing the scale of retrieval of fuel debris
and reactor internals(Development of technology related toensuring safety during fuel debris retrieval)(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 safety systems (Liquid/gas
phase systems, criticality control technology)
Development of analysis and estimation
technology for characterization of fuel debris

2) Development of the top access method

Development of technology for detailed
investigation inside PCV (Field validation of
the technology for detailed internal
investigation using X-6 penetration)(1) Development of technology for realizing theconcept of retrieving large structures① Method for cutting large structures② Large transfer container③ Large transportation equipment

Development of technology for detailed
investigation inside PCV(On-site demonstration of technology fordetailed investigation considering deposit
measures)
Development of technology supporting
integrated management of decommissioningat 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
and disposal of solid waste
Development of technology for containing,transfer and storage of fuel debris©International Research Institute for Nuclear Decommissioning5. Project Organization

No.24

Main sub-contracting details

Hitachi-GE Nuclear Energy, Ltd.

Mitsubishi Heavy Industries (MHI), Ltd.

[Sub-contracting details]
・ PCV connection sleeve remote installation test, HVH disassembly
element test, CRD exchanger disassembly element test, pump pit
interference removal element test

[Sub-contracting details]・ Design assistance related to detailing of cell structure(MHI NS Engineering Co., Ltd.)・ Design assistance related to detailing of the access equipment
installation method (MHI NS Engineering Co., Ltd.)・ Cell adapter remote installability verification test
(Nihon Kensetu Kogyo Co. Ltd.)・ Shielding door remote installability verification test
(Nihon Kensetu Kogyo Co. Ltd.)・ Installation position setting technology verification test
(Nihon Kensetu Kogyo Co. Ltd.)・ Design assistance related to detailing of procedures for removing
structures(MHI NS Engineering Co., Ltd.)・ Design assistance related to detailing of fuel debris collection
procedures(MHI NS Engineering Co., Ltd.)・ Verification test of the technology for remote removal of structures(Kobe University)
・ Fuel debris collection procedures verification test
(MHI NS Engineering Co., Ltd.)(Toko Corporation)
・ PCV connection sleeve remote welding test, element test related to
the RPV head, test manufacturing of large transfer containers, airtightness test
(Mitsubishi Heavy Industries, Ltd. (Former Mitsubishi Power, Ltd.))
・ Element test related to the method of cutting large reactor internal
structures(Sugino Machine Limited)・ Study related to filler material for the top access unitized large
structures transfer method(The University of Tokyo)
・ Design assistance related to the study of side access method(Hitachi Plant Construction, Ltd.)・ Design assistance related to the study of top access method(JTEC Corporation)
The outsourcing company for the following is yet to be determined・ Access tunnel additional shielding test (planned)
・ Shield plug disassembly element test (planned)
・ Large transportation equipment element test (planned)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project

No.25

1) Development of the side access method(1) Development of the method for installing access equipment
Solicitation items are listed.
① 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, installation and remotely installing the cell structure meeting this requirement via the connection
structure will be studied while taking earthquake measures into consideration. Then, the viability will beverified based on the on-site applicability of the method including the procedures, installation accuracy andefficiency, by element 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]① Installation of large heavy structures

No.26(1) Development results achieved so far and correlation with this project
Mini cask cell

[Development of Retrieval Method(FY2021-22)]• Substantiation of the access equipment (celladapter, shielding door, cell) to be connectedto the PCV inside the R/B, study andverification of feasibility of installation
method.

Shielding door

Cell adapter

Cask cell
Cell installation
deck
Mini cask cell

Waste transfer
cell

Canister carrying-in station
Canister cell
Access equipment carrying-in/out port

Cask cell(cask transfer inspection area)
Waste transfer cell

Waste carrying-in/out port

Cell installation
frame

Cask carrying-in/out port

Fuel debris retrieval cell

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

LLW transportation cask cell
Canister cell Fuel debris transportation cask cell

Pillar

Maintenance cell

Reactor Building Shield
Floor beam

Mini cask cell

Installation
cell frame

Frame structure

BSW

Debris retrieval cell
Reactorbuilding wall

Frame for supporting the load of the cell
1010
WorkPCVof makingan opening on PCV concrete wall
壁コンクリート開口作業

Fuel debris retrieval
preparatory cell
Dual arm typerobot containertransportation cask yard

Access equipment
temporary storage space

手順

Maintenance cell
Equipment transfer container

イ
メ
ー
ジ
図

Equipment transfer container yard

Cell downsizing

Cell adapter carrying-in and installation
1111 セルアダプタの搬入・設置作業
Temporary cell for
the work of making
開口作業用仮セル
an opening

Shielding door
(open)

遮へい扉（開口状態）

Cell
セルアダプタadapter

Cell installation inside the building
12 12
建屋内セル設置準備

Cell
セルアダプタadapter

Temporary cell for
the workof making
開口作業用仮セル
an opening

Material
carrying機材搬出入台車
in/out cart

Material
機材搬出入台車
carryingin/out cart

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

Track
Rail for carrying建屋内外結合
in/outthe cell for
セル搬出入用レール
linking the inside andoutside of thebuilding

Fixed rail 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 opening
1）開口作業用セル設営
2) Work of making an opening (Procedures opposite to2）開口作業（ガレキ等は搬入作業と逆手順で実施）
those for carrying-in work are followed for debris,※開口作業の進捗に従い遮へい扉を少しずつ閉じる
etc.)* The shielding door is gradually closed as thework of making the opening progresses.

1)
Preliminary preparation for carrying-in cell adapter
1）セルアダプタ搬入前準備(PCV wall surface cleaning / 3D shapemeasurement / cell adapter groove work)(PCV壁面清掃・3D形状計測/セルアダプタ開先作業)
2) Loading the carrying-in/out cart on to the outdoor rail
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
with the help of a yard building crane3)
Loading the cell adapter on the equipment carrying3）機材搬出入台車にセルアダプタを搭載
in/out cart
4)
Installing while adjusting the position in accordance4）ケガキに位置合わせを行いながら設置
with the layout markings•
Study of method of making an opening → A
・ 開口工法検討➡ PCV鋼板を損傷させない加工方法
method that would
not damage the PCV steel plate•
installation and installation of cell adapter•
Need for cell connection
flange, remote・ セルアダプタ据付・設置・ セル取り合い用フランジ要否,
遠隔搬入・設置工法
carrying-in and installation method(Installation of sling and roller for carrying-in at（開口部に吊ピース及び搬入用ローラの設置等）
・ 作業時の仮設遮へい方法
the opening)•
Method of temporary shielding during work

Procedure• Study on downsizing the cells installedinside R/B• Study of the method of supporting theload of the cells• Study of the work steps involved ininstalling the fuel debris retrieval
equipment

Equipment temporarystorage module
Maintenance cell
Fuel debris
retrieval cell

Canister cell

Layout of the fuel debris retrieval equipment[Further increasing the retrieval scale(FY2019-20)]

Crane maintenancemoduleShielding door

Illustrations• Study of the composition of fuel debris
retrieval equipment and the proposedlayout• Study of the method of installing thesuspension bridge type cell

Fuel debris retrieval cell

Need for finishing the surface of the opening
懸 •・ 開口部表面仕上げ要否•(Considering the impact on cell adapter installation)
念 • （セルアダプタ設置への影響考慮）
Specifications of the temporary cell for the work ofmaking an opening and dust measures once the事・ 開口作業用仮セル仕様及び開口時のダスト対策
opening is made項

Matters ofconcern[Upgrading of fundamental technology(FY2017-18)]

Equipment hatch cell
overhead crane
Carrying-in/out cell1)
Carrying-in and installing the fixed rail installation
1）固定レール設置台搬入・設置する。
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 the equipment
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 in accordancewith the layout markings
4）遮へい扉閉止後、開口作業仮セル解体
4) Disassembling the temporary cell for the work ofmaking an opening, after the shielding door isclosed•・ X-6
Methodof removing the X-6 penetration and
ペネ撤去工法及び汚染管理
contamination control

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.27① Installation of large heavy structures(2) Background and purpose of this research✓
Reasons for this research• The side access method has been studied 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, in order tofurther increase the retrieval scale of fuel debris and reactor internal structures. In FY2020-21, the access equipment wasstudied such as downsizing the cells to be installed inside the R/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 connecting part, the cell structure needs
to be positioned accurately on the PCV connecting part while keeping within the load limit for the floor inside R/B, andthe 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 by earthquakes, and the structures and requirements toaccomplish this need to be clearly specified.
➢ As the pedestal opening cannot be modified and changed easily, while connecting the X-6 penetration, which is thelocation where the access equipment is installed, to the PCV opening, the mutual correlation between the locations ofboth openings (the axis joining the openings) is sufficiently considered, and the access equipment is installed along theaxis leading to the pedestal opening from the X-6 penetration. Hence for remotely installing the cell structure, theprocedures for carrying-in the cell structure and installing it accurately, while meeting these requirements, need to beestablished.
• Therefore, in order to install the access equipment accurately inside the R/B, ensuring installation accuracy and optimizationof installation work need to be studied and related development needs to be carried out with respect to the cell structure andconnection 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 the required
specifications of the equipment for remote operation• Reflection destination and contribution of the outcome: Establishment of the method for installing the access equipment
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]

No.28① Installation of large heavy structures(3) Project Goals✓
Requirements from the reflection destination• The access equipment is planned to enter from the pedestal opening of the PCV to retrieve fuel debris.
• An access route for the above-mentioned access equipment needs to be made in a straight line from thepedestal opening to the X-6 penetration.
• Hence, the shielding door or the cells, etc. which are large heavy structures, need to be installed accurately
along that straight line.
• Also, the connecting 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 an earthquake.
• 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. Hence installation by remote operation
becomes necessary.
✓ Goals based on the above-mentioned requirements• Studying the required installation 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]① Installation of large heavy structures

No.29(4) Implementation items, their mutual correlation, and correlation with other research✓ Implementation items and correlation between the implementation items
Substantiation of the specifications of components of the access equipment•

Substantiation of specifications of access equipment and clear specification of installation
requirements

Study on detailing of procedures for installing the access equipment••

Detailing of installation procedures
Substantiation of installation tools

Verification of element test for the installation procedures••

Designing and manufacturing of equipment for the element test
Identification of issues in implementation of element tests and in the specifications of theequipment for remote installation

Organizing the required specifications of the equipment for remote installation•

Identification of required specifications of the equipment 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]① Installation of large heavy structures

No.30(4) Implementation items, their mutual correlation, and correlation with other research✓ Correlation with other research (Input and output information)：Items studied particularly in FY2021-2022
Work
step

Ground preparation in front of
the R/B

Removal of interference objects
inside the Reactor Building(Removal of RHR pipes, etc.)

Removal of BSW in front of airlock and around X-6 penetration

Creation of opening in thebuilding wall outside the R/B⓪ Current state
G/H

Laid iron plate
Trench Crushed stone

TP+8,900① Digging down TP+8,900-300mm

Illustrationof work
steps

IndoorOpening forentry of workers

Existing ground

Outdoor

Building opening forfuel debris retrieval cell

Digging down
TP+8,900

G/H
Crushedstone

Existing ground② Ground preparation using concrete
Ground preparation
using concrete

Scope of ground
preparation

G/H

Building opening forthe mini cask cell
G/H

TP+8,900

Simple tent house
Crushedstone

Remarks•

Existing ground

Shielding door base plate andshielding door installation

Work
step

• Conceptual study on the method
implemented in FY2019-2020

Conceptual study on the method
implemented in FY2019-2020

Setting up the outdoor yard

• Conceptual study on the method
implemented in FY2017-2020

Laying of rail for carrying thecells in and out of the building
Rail for carrying
the cell in and out

電動フォークMotor operated
fork
Installation of base plate

Building

Installation of base plate

G/H

Installation of laid iron plateforOverhead retractableCrane
outdoor
yard

cart

•

Illustration of outdoor yard
(Overhead retractable
tent house)

Basement
floor

Shielding door

Conceptual study on the method
implemented in FY2017-2020

Crushedstone Existing
groundConcrete

Basement
floor

Penetration plug

Installation of rail
Laying the rail

carrying-in/out

Installation

Remarks

Motor
電動フォーク
operated fork

Base plate

Track

Shielding door
G/H

Base plate forthe rail

Retractable
part

Illustrationof work
steps

Shielding door

TemporaryshieldingAnchor casting area

Base plate for the rail

BSW opening

Basement
floor

Crushedstone Existing
groundConcrete• Conceptual study on the method
implemented in FY2019-2020

Base plate
Laid iron plate

PCV

Penetration plug

cutting
Closing plate

Basement
floorCore boring• The method of making a hole developedby Toshiba in FY2017-18 is planned toused.

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

No.31① Installation of large heavy structures(4) Implementation items, their mutual correlation, and correlation with other research✓ Correlation with other research (Input and output information)：Items studied particularly in FY2021-2022
Work
step

Carrying-in and installation ofcell adapter

Fuel debris retrieval cell

Air-tight door

PCV concrete wall

PCV wall opening
Carrying-in of thetelescopic dual arm

Shielding door

Confinement boundary

Weldingequipment
and tool rack

Illustrationof work
steps

Comprehensive trial run andinspection

Shielding door closed

Robot arm for welding

Cell adapter
grabbing arm

Installation of fuel debris retrieval
cell and other structures

Fuel debris retrieval cell
Mini cask cell

Fuel debris retrieval
back-up cell

Welding
location

Maintenance cell
Canister cell

Shielding door

Debris retrieval cell Cell adapter

バウンダリの構成
Configurationof the boundary

Debristransportation
container cell

R/B boundary (assumed)

Cell adapter
Cell adaptertransportation cart

Crawler craneWelding溶接個所
location

LLW transportation
container cell

Push jackTent house

Remarks
Work
step

•

Conceptual study on the method
implemented in FY2019-2020•• Conceptual study on the method
implemented in FY2017-2020

Conceptual study on the method
implemented in FY2019-2020

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 the pedestal (1)(Telescopic dual arm type robot)

Removal of interfering objects
from inside the pedestal (2)(Telescopic dual arm type robot)• Conceptual study on the method
implemented in FY2017-2020

•

•

•

Illustrationof work
steps

Remarks

Conceptual study on the method
implemented in FY2017-2020

Conceptual study on the method
implemented in FY2017-2020

Conceptual study on the method
implemented in FY2017-2020©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.32(4) Implementation items, their mutual correlation, and correlation with other research✓ Correlation with other research (Input and output information)：Items studied particularly in FY2021-2022
Work
step

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

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

Sub-criticality measurement

Fuel debris retrieval(Fixed rail type dual arm typerobot)： Scope of studies
conducted in FY2021-22

Constant
monitoring

Illustrationof work
steps

Remarks

Sub-criticality
measurement• Conceptual study on the method
implemented in FY2017-2020• Conceptual study on the method
implemented in FY2017-2020

Fuel debris transfer

Fuel debris retrieval(Hydraulic arms)

Work
step

• Conceptual study on the method
implemented in FY2017-2020

CRD removal• Conceptual study on the method
implemented in FY2017-2020

Fuel debris delivery

Unit canCanister cell

Transport
ation cart

Illustrationof work
steps

Fuel debris
retrieval cell

Unit canWinch

Fuel debris
transportation cask cell

Remarks•

Conceptual study on the method
implemented in FY2017-2020•

Conceptual study on the method
implemented in FY2017-2020•

Conceptual study on the method
implemented in FY2017-2020

Mini cask cell

• Conceptual study on the method
implemented in FY2019-2020©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.33(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Objective••

In order to install the cell structure, which is a large heavy structure, on the PCV connecting part, the cell structureneeds 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 the structure equipped withconfinement function and a function for dealing with displacement caused by earthquakes. The structures andrequirements 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 thefloor 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 absorption function, andthe structure.
Also, to add the required installation accuracy and method of adjusting the position while installing, to the structural
study.

✓ Comparison with existing technologies••

The cell adapter, shielding door and cell that are the components of the access equipment are technologies that arepresent in existing nuclear facilities.
Since the access equipment, which comprises large and heavy structures, has to be installed accurately inside theexisting R/B at the Fukushima Daiichi Nuclear Power Station, and the cell adapter has to be installed 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]① Installation of large heavy structures

No.34(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and results
1) Connection structure of the boundary with the PCV➢➢➢➢

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 connected by welding the bolt and the seal.
The confinement boundary comprises the fuel debris retrieval cell, shielding door (casing) and the cell adapter.
Base plate

Base plate

Shielding door
(Casing)

BSW

Shieldingdoor

Cell adapter
Connecting
flangeWelding(Remote operation)

PCV

Shielding door

Cell adapter
Welding(Remoteoperation)

Welding(Remoteoperation)

Shielding door

[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: 180 ton

Welding
locations(Inside the cell)
Fuel debris retrieval cell

Fuel debris
retrieval cell

[Confinement boundary]

Bolt connection
location(Outside the cell)[Connection 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.35: Loadmass point(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and results
1) Connection structure of the boundary with the PCV (2/5)[Shielding door]

Rail part and anchor casting part(enlarged view)
Cross section a

Fuel debris retrieval cell

Fixed on the strong members using post installed anchors
Shielding door

Rail part (enlarged view)
Cross section b

Rail for carrying in the cells
Fuel debris retrieval cell

Shielding door
Shielding door

Shielding door housing

Connecting part of the rail for carrying-in
the shielding door and cell
(Enlarged view) Cross section c(Shielding door housing)

Dimensions of the X-6 penetration(height/allowance)(Concrete opening)(External dimensionsof cell adapter)(Effective opening)(Effective opening)(Shielding door opening)(Concrete opening)(Cell adapter flange)

Tie rod lug
for shipping(PCV opening)(Shielding door housing)(Shielding door)(Concrete opening)(Cell adapter flange)(Shielding door opening)(Concrete opening)(External dimensions of cell adapter)(Shielding
door)[Illegible] rail+
hydraulic rail

(PCV opening)©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(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and results

No.36

1) Connection structure of the boundary with the PCV (3/5)[Boundary part]A structure such that the shielding door (casing) can be connected to the cell adapter flange part.
[Carrying-in of cell adapter ②][Carrying-in of cell adapter①]
Shielding door

BSW

[Welding of cell adapter]

BSW

PCV

BSW

[Opening of PCV]
Fuel debris
retrieval cell

BSW

Welded part

Boundary

Cell adapter

X-6 penetration(Cut)©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.37(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and results
1) Connection structure of the boundary with the PCV (4/5)(Concrete opening)(Cell adapter flange)[Boundary part](Concrete opening)(Cell adapter external
dimensions)(Effective opening)(Concrete opening)(Effective opening)(Cell adapter external
dimensions)(Shielding door opening)(Concrete opening)(Cell adapter flange)(Shielding door opening)[Illegible] rail +hydraulic arm

Illustration of cell adapter(PCV opening)

Items

Width (mm)Height (mm)Dimensions

Clearance

Dimensions

Clearance

Effective opening

2, 840100

2, 690100

PCV opening

2, 940210

2, 790210

Cell adapter dimensions

3, 150430

3, 000430

Concrete opening

3, 580—3, 430—Shielding door opening

3, 250100

3, 632100

Cell adapter flange

3, 350—3, 732—©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.38(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and results[Cell adapter structure]1) Connection structure of the boundary with the PCV (5/5)[3D-CAD of boundary structure]

Shielding door
This bolt is for shipping purposes.
It should be removed without fail after plumbing

Relative displacement: Planned to be±10mm

Cell adapter
PCV

Fillet welding

X-6
penetration
PCV side

Fixed rail
installation
Fillet welding
platform
Cell side

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

Bellows corner section©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.39(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and results

2) Procedures for installing 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 andcell adapter: Welding (2 locations)② Installation of base plate③ Installation of shielding door

④ BSW opening(Temporary closure and reductionin length of X-6 penetration)

Connecting the fuel debris retrieval celland shielding door (outside) Bolts
Carrying-in of thetelescopic dual arm⑤ Installation of cell adapter(remote operation)⑥ Installation of fuel debris retrieval cell
Connecting the fuel debris retrieval celland shielding door (inside): Welding⑦ Making an opening in PCV⑧ Laying of fixed rail forinternal interference removal©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.40(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and resultsa) 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 straight line needs to be established.
➢ In other words, the fixed rail and the rail inside the cells need to be installed along thestraight 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]① Installation of large heavy structures

No.41(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and resultsb) Deviation occurred during installation[1] 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 referenceline 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 the pedestal
opening and the fixed rail
Rail installation reference line
Rail installationreference line

Reference line
for installation

Reference line
for installation[1] Rotational direction[2] Horizontal direction©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.42(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and resultsc) Setting the installation accuracy for the rotational direction

1°

0.18m

➢ 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

Reference line for
installation

Fixed rail
BSW
Fixed rail installation platform

Pedestal

Clearance of the pedestal opening and the fixed rail

Pedestal
opening
BSW

Fixed rail

©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.43

Amount of increase ingroove gap△x(mm)(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and resultse) 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

Extent of deviation of central axis of 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.44(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and resultsf) Other: Actions to be taken in the event of an earthquake during installation
Even though 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 during installation, 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.
In this manner, the confinement function of the PCV is maintained during installation.
➢ During the work of making an opening in the BSW or the outer wall of the R/B, G/H is installed as a measure toprevent 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]① Installation of large heavy structures

No.45(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Implementation items and resultsg) Summary

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 installation the casing, work in confined spaces, and welding work
② Indication of specifications for the equipment for 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.46(5) Implementation items(5)-1: Substantiation of the specifications of components 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. 34, 35, 36, 37, 39, 41, 42, 43, 45)• A structure that requires minimal on-site welding work is used. (Reference: No. 34, 35, 36, 38)• 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. 34, 35)✓ 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]① Installation of large heavy structures

No.47(5) Implementation items(5)-1: Substantiation of the specifications of components 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, was substantiated. (Reference: No. 34, 35, 36, 38, 38,
39)
As part of the substantiation mentioned above, the installation accuracy and the 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]① Installation of large heavy structures

No.48(5) Implementation items(5)-1: Substantiation of the specifications of components of the access 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 relevant tothroughput calculation.
➢ In order to enhance throughput, the work carried out inside the cells at the time of fuel debris
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 maintenanceneeds 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.
◯ Assumption of failure mode of the components inside the cells◯ Assessment of the extent of impact on retrieval work

◯ 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.49(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellsb)-1 Material handling flow (Fuel debris handling line)
Shielding door
Lifting up the accessequipment from the unit cantransportation cart

Fuel debris
retrieval cell①②③④⑤

Air-tight door(+ shielding door)

Details on ① to ⑰ in the figure areprovided on the following page.

Dual arm
type robot

Cell adapter

Temporary storage

Draining
equipment

LLW
LLW3D
Weight scale / Assignment of ID/
Equipment for
dosimeter / measuremen
dosimeter capturing
images weight scale t equipment
inside the can⑥⑦
Canister cell

Fuel debris retrieval cell

Fuel debris retrieval
preparatory cell⑨⑩⑪⑫⑬⑭
Double door⑧
Doubledoor*Number of containers:
5 containers

Canister
Mini cask cell

Air-tight door⑮

Fuel debris
transportation cask cellSurface Water cleaning
contamination and air drying
inspection
transportation
Air-tight door Debriscask
yard*Surface contamination verification

Stand-by pit

Fuel
Fuel debris
transportation cask cell⑯⑰

Unit canOutdoortransfer

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.50① Installation of large heavy structures(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellsb)-2 Material handling flow (Fuel debris handling line)① The unit can containing fuel debris is transported from inside the PCV by means of a transportation cart.

Fuel debris
retrieval cell

Mini cask cell

② The unit can is grabbed by means of the dual arm type robot and is stored temporarily in a temporary storage container with ashield.
③ The unit can is removed from the temporary storage container by means of the dual arm type robot, and is placed inside thedraining 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 are measured.
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 (Master Slave Manipulator*) 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 fueldebris transportation cask.
⑭ The lid of the fuel debris transportation cask is closed by means of a dedicated crane and the MSM.
Fuel debris
transportation cask cell 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
Fuel debris
external appearance, air-tightness test, surface contamination inspection, etc.
transportation⑰ The fuel debris transportation cask is transported to the storage preparation facility by means of the transportation vehicle.
cask yard

Canister cell*： 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 here 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 of Japan, etc.
©International Research Institute for Nuclear Decommissioning

No.51
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellsc)-1 Material handling flow (LLW* handling line)

Air-tight
door
Air-tight door(+ shielding⑤⑥①②③④ (+ shielding door)*The dual arm type robot directly
Fueldebrisretrievaldoor)
enters the inner container from the Fuel debris retrieval cell
preparatory cellaccess equipment

Shielding door

Maintenance cell

Details on ① to ⑯ in the figure areprovided on the following page.

Dual arm
type robot

LLW weight

Assignment of ID /Temporary storage
scale / dosimeter Capturing of images of the inside of the inner container
Cell adapter
draining equipment, etc.
Fuel debris retrieval Air-tight door
LLW transportation⑦⑧⑨⑩⑪⑫preparatory cell
cask cell

LLW canister

Surface
Water washing contamination
and air drying inspection

Waste storage container⑬⑭⑮⑯
LLW transportation
cask cell

Air-tight door

LLW transportation cask yard

Waste transportation cask

*Surface contamination verification andverification of external appearance*
Outdoortransportation

Inner
container
Waste storage
container

LLW canister
Waste transportation
container* 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]① Installation of large heavy structures(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellsc)-2 Material handling flow (LLW handling line)

Fuel debris
retrieval cell

①
②
③
④

Fuel debris
retrieval
preparatory cell
LLW
transportation
cask cell

⑤
⑥
⑦
⑧
⑨
⑩
⑪

LLW
transportation
cask yard

⑫
⑬
⑭

⑮
⑯

No.52

The inner container containing LLW is transported from inside the PCV by means of a transportation cart.
The inner container is lifted up by means of the dual arm type robot, and its weight and dose are measured.
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.
The inner container is loaded on the transportation cart by means of the dual arm type robot, and transported to the fueldebris retrieval preparatory cell.
The inner container is hoisted by means of a jib crane, and delivered to the LLW transportation cask cell.
The LLW that is hoisted by means of the jib crane is received in the LLW transportation cask cell.
The inner container is placed in the LLW canister.
The lid of the LLW canister is closed by means of an overhead crane and MSM.
The LLW canister is hoisted by means of the overhead crane, and the contamination on its surface is inspected.
The LLW canister is washed with water and air dried at the LLW canister washing area as required based on the resultsof the surface contamination inspection.
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.
The lid of the waste storage container is closed by means of a dedicated overhead crane.
The waste transportation cask is transported to the LLW transportation cask yard by means of the transportation cart.
The waste transportation cask undergoes various inspections to be conducted before transporting out such as
inspection of external appearance, surface contamination inspection, etc.
The waste transportation cask is loaded onto the transportation vehicle.
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6. Implementation Items of This Project[1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures

No.53(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellsd)-1 Material handling flow (Fuel debris retrieval robot arm handling line)
Shielding door

Air-tight door(+ shielding door)①②③④

Air-tight door(+ shielding door)⑤

Dual arm type robot

Details on ① to ⑪ in the
figure are provided on thefollowing page.

Access equipment(failed arm)

Cell adapter

Fuel debris retrieval cell

Fuel debris retrieval preparatory cell

Maintenance cell

Equipment transfer container yard⑥⑦

Air-tight door(+ shielding door)

Temporarystorage space
for the dual
arm type
robot

⑧⑨⑩⑪

Temporary storage space
for the access equipment
Air-tight door(+ shielding door)

Accessequipment for
replacement
Verification ofmaintenance
operation

Transfer
At thetime 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]① Installation of large heavy structures

No.54(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellsd)-2 Material handling flow (Fuel debris retrieval robot arm handling line)

At the time of carrying-out①

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.

Fuel debris retrieval⑤
preparatory cell

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

Fuel debris
retrieval cell

Maintenancecell⑥

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.

Equipment⑨
transfer container
yard⑩

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

⑪

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

Equipment transfer container is loaded on to 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 the access 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]① Installation of large heavy structures

No.55(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellse)-1 Material handling flow (Overhead traveling dual arm type robot handling line)
Shielding door

Air-tight door(+ shielding door)

Air-tight door(+ shielding door)

Details on ① to ⑨ in the figure areprovided on the following page.

Dual arm type robot(failed)Cell adapter①②③

Fuel debris retrieval cell

Fuel debris retrieval preparatory cell

Dual arm typerobot forreplacement Double
door

Air-tight door(+ shielding door)

Maintenance cell

Failed dual arm
type robot

Access equipment
temporary storagespace
Air-tight door(+ shielding door)

To the preparatory cell

Access equipment
temporary storage space

Replacement

Operationverification

To the preparatory cell

Maintenance

④⑤

⑥⑦⑧⑨

Maintenance cell(while carrying-in for replacement)

Maintenance cell(while carrying-out 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]① Installation of large heavy structures

No.56(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellse)-2 Material handling flow (Overhead traveling dual arm type robot handling line)

At the time of carrying-out
Fuel debris
retrieval cell①

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.

Fuel debris retrieval ③
preparatory cell④

Maintenancecell

The dual arm type robot is moved to the maintenance cell.
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 fueldebris retrieval cell.
©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(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cells

No.57f) Heating, Ventilating and Air Conditioning System for each cell
Flow of ventilation in each cell

R/B

Tent house

Shielding door
Dual arm
type robot
container

Negative pressure area

M

M

Robot
arm
containerAir ⇔ (N)*2

Cell adapter

N2

M

Air

Air

-200
Air

Air

-200
M
M
Negative pressure （-20/-30）
Fuel debris transportation
cask cellAir

UC(with hole at the bottom)
M

Innercontainer-200

LLW transportation
cask cell

PCVStand-by cell

Maintenance cell

M
Air
Waste storage
container
LLW transportation cask cell
Wastetransportation Canister cellcask
MCanister

M

Air⇔
(N2)*

-300
Air -200

Air

Air -200
M

Legend-400-400

Fuel debris retrieval cell-200(-400)-200(-400)
M

Air

M

Exposure
evaluation
Air ⇔2(N)*Exposure evaluation

During normal operation

Air

-200

-200
Mini cask cellM

: Air-tight door
: Double door
(air-tight): Shielding door
(Not air-tight): Air supply: Exhaust

N2 : For controlling oxygen
concentration

M : Monitoring: Fuel debris: LLW
・ Exposure assessment:
The extent of impact of the radiation and radioactive
materials radiated, emitted from the reactor isassessed. It is confirmed that the effective dose
received by the public in the areas in the vicinity ofthe 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]① Installation of large heavy structures

No.58(5) Implementation items(5)-1: Substantiation of the specifications of components of the access equipment✓ Other: Detailing of the work carried out inside the cellsg) Summary•

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 be handledinside the cells and their form, and considering that the inside of the cell needs to basically have negative
pressure from the viewpoint of confinement, that spread of contamination needs to be prevented, that theatmosphere and environment inside the cells is the same as the PCV as the cells are connected to the PCV, etc.
Specifically, the flow of air supply/exhaust, type of atmospheric gas inside the cells and the monitoring position
were studied.

H) Future plans•

The following items will be studied focusing on the cell line handling fuel debris.
〇 Assumption of failure mode of the components inside the cells〇 Assessment of the extent of impact on retrieval work
〇 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.59(5) Implementation items(5)-2: 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
No.60[1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(5) Implementation items (5)-2: Study on detailing of procedures for installing the access equipment[Result]: Overall step diagram
No.

1. Work of ground preparation outside the R/B

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

2. Removal of RHR pipes inside the R/B

Remoteoperation
Local exhaust
ventilation system

Conceptual drawing

RHR
pipe

In front of personal air lock
Equipment
carry-in route

Ground preparation area

Western street
Inside R/B

Laid iron plate

G/H

Inside R/BGroup preparation
using concrete

Crushedstone▽TP９.４m▽TP８.９m▽TP8.9m

Existing
ground▽TP8.9m

Procedure

RHR
pipe

G/H

Workers enterfrom the access lock
Sheet
Wire saw covering
Sheet covering
G/H
Local
exhaustventilation
systemLocal exhaust
ventilation system

Equipment
carry-in route

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

Temporary shielding

Cutting
location

Cutting
location

Crushed Existingstone ground

Current state of the outdoor area After ground preparation work

Remarks

Shielding wall for
X-6 penetration

Illustration of G/H

Illustration of cutting the
RHR pipes

Step (2): Installation of temporary shielding

The embankment in the area on the west side outside
the R/B is flattened so that its floor level is the same as
the floor 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 tobe removed, and after a blowing agent is filled, thepipes 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 thewestern passageway are removed using an electric
crane, and a temporary shield is installed in front of thepersonnel access lock. Thereafter, 3D measurement of
the form of the surface of the PCV concrete wall is
performed.

General construction work

Negative pressure is created in G/H using the local
exhaust ventilation system, etc. to control dust andprevent its dispersion inside the building.

The G/H used at the time of cutting the RHR pipes is used.
New G/H is not installed. The jacket type shield which had
been used in the past at Mitsubishi Heavy Industries, Ltd.
is used as temporary shielding.
©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(5) Implementation items (5)-2: Study on detailing of procedures for installing the access equipment[Result]: Overall step diagram
No.

4. Making an opening in the building wall outside theR/B

5. Centering and layout marking inside and outside thebuilding

6. Installation of shielding door base plate

Building frame (Blue color)

Conceptual drawing

Opening for entry
of workers

Shielding door base plate

Base line (reference)
Temporary shield

Building opening forthe fuel debris retrieval cell

Center of the rail
Electric shutter

Cart forinstallation

Area for anchor placement
Simple tent
house

Illustration of layout marking inside R/B
Building opening for the mini cask cell

Building opening for the fuel debris
retrieval cell

Indoor Outdoor

Shielding door base plate

Remarks Procedure

Building opening for the mini cask cell

Simple tent house

Illustration of layout marking outside R/B

Illustration of the shielding door base installation

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

After marking the locations on the PCV concrete wall (opening)inside the R/B, the installation location of shielding door baseplate, and the location for laying the rail, etc., the markings areextended on the floor of the outdoor yard.

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

The simple tent house and the work of making openings inthe building carried out at the PWR plant have the same
results(Reactor internal structures replacement work, etc.)

General construction work

The results of the 3D measurement of the PCV concretesurface are reflected in the base plate form.

©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(5) Implementation items (5)-2: Study on detailing of procedures for installing the access equipment[Result]: Overall step diagram№

7. Shielding door installation
Shielding door frame /shielding door
Installation cart

8. Laying of rail for carrying the cells in and out of
the building

9. Installation of outdoor tent house

Rail for carrying
the cells in and out

Conceptual drawing

Base plate

Electric fork
Arrangement of
the rail within the building

Rail for carrying in the cells

Remarks

Procedure

Illustration of the shielding door installation
The shielding door frame / shielding door is carried in bymeans of the installation cart and bolted.

―

Arrangement of the rail outside the building

Outdoor tent house

The rail is installed inside the R/B by means of the electric fork,
and the base plate is installed outside the R/B by means of acrane, etc.
After laying the rail, the work of centering and leveling the rail iscarried out inside and outside the building.

Tent house is installed at the outdoor ground preparation
location.
(Installed so that it covers the area where the cells are
installed.)
The ancillary facilities and utilities are set up and installed.

The base plate installation and rail installation work carried out
at the PWR plant has the same results.
(Reactor internal structures replacement work, etc.)

The roof of the tent house is planned to be retractable so thataccess can be provided to the crane, etc. for transferring the
LLW and debris storage cells.

©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(5) Implementation items (5)-2: Study on detailing of procedures for installing the access equipment[Result]: Overall step diagram
Issue: Processes concerning establishment of the boundary№

10. Making a hole in the PCV concrete walland cutting the X-6 penetration
Shielding door
Temporary shielding

Conceptual drawing

Green house

11. Carrying-in and installation of cell
adapter
Robot arm for welding

Arm for grabbing
cell adapter
Welding equipment
and tool rack

Mini cask cell

Canister cell
Fuel debris
transportation cask cell
Cell adapter
Cell adapter transportation cart

Green house

PCV concrete wall

Penetration plug

Penetration
plug

Procedure

X-6
penetration

Closingplate

The cell for making the hole is installed, and an
opening is made in the PCV concrete (BSW) wall. X-6
penetration is cut when the opening is being made anda closing plate is installed.

LLW transportation
cask cell
Air-tight door

Shielding door

Confinement boundaryCore boring (Example of method of making an opening)

Shielding wall
Welding
location

Cutting

Remarks

12. Installation of theequipment/equipment transfer system cell

Cell adapter
Welding location

After carrying out the work of cleaning the PCV wall
surface, conducting 3D measurement and making thecell adapter groove, the cell adapter is carried in using
the cell adapter transportation cart and installed.
The shielding door and the cell adapter are welded
together.

Fuel debris retrieval cell

Cell adapter

After closing the shielding door, the cell is temporarily
placed on the rail with a crane, and then is carried inand joined (welded).
After the cell is joined, a pressure resistance test of theinside of the cell is conducted.
Similarly all cells are carried in and installed.

The results of past subsidy projects are utilized to the
maximum in the method of making the opening in the
PCV concrete wall (BSW).
©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(5) Implementation items(5-2: Study on detailing of procedures for installing the access equipment[Result]: Method of installing the boundary components

No.64

PCV steel plateX-6 penetration

Base plate

Shielding door

① Installation of base plate② Shielding door installation
Connecting the shielding door and cell
adapter: Welding (2 locations)③ BSW drilling (Temporary closure and reductionin length of X-6 penetration)
Connecting the fuel debris retrieval cell and shielding door (outside): Bolts[Issues]
Since the cell adapter is installed after making the
opening in the BSW, the installation work needs tobe carried out by remote operation in order toprevent the impact of radiation dose from the PCV.
Also, when the cell adapter is carried in for
installation, it needs to be carried in while avoiding
the connecting parts for establishing the boundary
and the interfering objects.

Connecting the fuel debris retrieval celland shielding door (inside): Welding④ Installation of cell adapter (remote operation)⑤ Installation of fuel debris retrieval cell
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project
No.65[1) (1) Development of the Method for Installing Access Equipment]① Installation of large heavy structures(5) Implementation items (5)-2: Study on detailing of procedures for installing the access equipment[Result]: Cell adapter installation procedure№

1. Cell adapter positioning and straightmovement
Base plate (Yellow)

2. Confirming for interfering objects infront of the shielding door
： Interfering objects confirming location

3. Carrying-in of cell adapter (loweringand straight movement)

4. Confirming the boundary components： Interfering objects confirming location： Interfering objects confirming location

Shielding door
(Blue)

Conceptual drawing

BSW

Cell adapter (Green)

Cell adapter (Green)

Cell adapter (Green)
Cell adapter(Green)IssuesProcedureX-6 penetration(Red)

With the shielding door “open”, theposition of the cell adapter is adjusted in
the vertical and horizontal direction suchthat it does not interfere with theshielding door frame.

The cell adapter is moved forward, andafter the cell adapter passes theshielding door frame, the transportation
cart is stopped and presence of any
interfering objects is confirmed.

The cell adapter is moved forward, andinserted while making sure it does notinterfere with the BSW and X-6
penetration part with the help of acamera. Once near the X-6 penetration,
the cell adapter is lowered to avoid
interfering with the X-6 penetration.

After installing the cell adapter, eachboundary component is confirmed bymeans of a camera.

Method of confirming for interfering
objects

Method of positioning the tip of the cell
adapter with the PCV steel plate

Method of confirming the gaps with theboundary©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project
No.66[1) (1) Development of the Method for Installing Access Equipment][Legend]① Installation of large heavy structures
Element test ① Overall verification test(5) Implementation items
Element test ② Unit 5 Field investigation(5-2: Study on detailing of procedures for installing the access equipment Element test ③[Result]: Issues in the cell adapter installation procedures and response measures
Work step

Issue

Method of resolving the issue

Test plan

Remarks

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

Establishment of the method of scanning from the X-6
penetration location to the CRD opening and themethod of making the marking for the cells• Desk study of the scanning method and marking[Elemental test ①]

technique will be conducted.

• 1/1 scale simulation• The feasibility of the methods studied will be verified• Ascertaining the coordinates byusing simulated bodies.

means of 3D measurement· Status at Unit 5 will beverified(FY2022)

2. Installation of shielding door
Checking of the status of BSW rebars for placing post
installed anchors(1) Installing the shielding door base plate• Will be verified at Unit 5 for reference-• Desk study-

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

(3) Making an opening in the PCV concrete
wall and severing X-6 penetration

Method of carrying-in, transportation and installation ofshielding door
① Making an opening in the concrete② Method of cutting X-6 penetration③ Dust behavior when the opening in concrete is made• Rebars in Unit 5 will be
explored (FY2022)-① Subsidy projects that have been implemented in thepast are planned to be utilized.

-② Desk study will be conducted③ Dust behavior is planned
to be analyzed③ Circumstances will be estimated through analysis

3. Cell adapter processing• Desk study(1) Polishing the surface adjoining the PCVStudy of method of polishing by means of remote(Identification of specifications required for remotewall surface

operation

operation)

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

(2) Performing 3D measurement of the surface
adjoining the PCV wall surface

(3)

(4)
(5)

with the marking location of the fitting reference line as Viability of the studied methods will be verified using
a guideline

simulated bodies

Manufacturing the cell
Carrying

adapter• The cell adapter will be manufactured on a trial basis

out work Processing the cell
Advisability of processing the flange based on theat theadapter connecting flange results of 3D measurement

using the results of the 3D measurement performed inplantchecked, and viability of processing will be verified.

Connecting the cell
adapter and flange(2), whether or not it fits on to the simulated PCV will be-[Elemental test ②]--• 1/2 scale simulation• Ascertaining the form by means of
3D scanning-• Manufacturing of simulated cell
adapter-(Verification of fitting)-©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project[1) (1) Development of the Method for Installing Access Equipment][Legend]① Installation of large heavy structures
Element test ①(5) Implementation items
Element test ②(5-2: Study on detailing of procedures for installing the access equipment Element test ③[Result]: Cell adapter installation procedure
Work step

Issue

Method of resolving the issue

No.67
Overall verification test
Unit 5 Field investigation

Test plan

Remarks

4. Cell adapter connection work
(1) Inserting the cell adapter in the BSW

Interference of shielding door and BSW concretewith the machined surface• Checking for interfering objects by inserting using simulatedbodies-• Identification of specifications required for remote operation(2) Aligning, welding and inspecting the cell adapter• Desk study of the method① Aligning the cell adapter on the PCV side

② Aligning the cell adapter on the shielding door side

Establishment of the method of positioning the cell

• Verification of viability of the methods studied using simulated

adapter on the PCV steel platebodies[Elemental test ③]• Identification of specifications required for remote operation• 1/2 scale simulation• Desk study of the method(Part which will be checked for

Establishment of the method of positioning the cell
adapter on the shielding door side

• Verification of viability of the methods studied using simulated interfering objects will be at 1/1 scale)• Checking for interfering objects
bodies• Identification of specifications required for remote operation-• Verification of positioning(Accuracy ±7.5mm or less)• Desk study of the method③ Measuring the gap between the cell adapter and the Establishment of a method of gap measurement by• Verification of viability of the methods studied using simulated

PCV surface

bodiesmeans of remote operation-• Verification of gap measurement-• Identification of specifications required for remote operation• Desk study of the method④ Measuring the gap between the cell adapter and the Establishment of a method of gap measurement byshielding door framemeans of remote operation

Establishment of a method of welding the cell
⑤ Welding the cell adapter to the PCV wall surface

adapter and the PCV steel plate by means of remote
operation
Establishment of a method of welding the cell

⑥ Welding the cell adapter to the shielding door side

adapter and the shielding door by means of remote
operation• Verification of viability of the methods studied using simulated-bodies• Identification of specifications required for remote operation• Desk study• Identification of specifications required for remote operation(Results of existing subsidy projects will be used)• Desk study• Identification of specifications required for remote operation

-

-

-

-

-

-

5. Cell installation(1) Closing the shielding door--

[Overall construction verification test](2) Carrying-in the cell-

• Carried in by means of usual methods (TIR roller, etc.) using
simulated bodies (including rail)• 1/2 scale simulation-(Cell length about 1m)

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.68① Installation of large heavy structures(5) Implementation items(5)-2: 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 access method.

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

✓ Issues
Work through the X-6 penetration and work after removing BSW is carried out under high-dose radiation environment andhence needs to be carried out by remote operation. (Remotely carrying out the following work, in particular, is challenging.)
・ 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.69(5) Implementation items(5)-2: 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, but the method of establishing the reference line is still being
studied at present.
② Detailing of installation procedures of the cell adapter, which are believed to be technically highly difficult: The study of procedures for carrying-in the cell adapter has been completed. The installation
procedures are being studied.
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. Resolution of these issues isbeing studied.
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 when carrying-in and installing the cell adapter✓ Future plans
・ Detailing of the procedures being studied and clear specification of the method for resolving the issues will
be continued.
(The procedures are planned to be finalized by element tests)©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.70(5) Implementation items(5)-3： Element test verification of 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 the viability of the following issues identified in (5)-2 by element tests and workability in caseof remote operation.
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(Remote operations are not 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 were conducted concerning the following issues identified in (5)-2 using test pieces.
[Results]： ① Element test plan
② Study of the element test details and test pieces, and arrangement of the pieces③ Implementation of element tests, provision of the results as feedback for the study on detailing of eachmethod©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project[1) (1) Development of the Method for Installing Access Equipment]

No.71① Installation of large heavy structures(5) Implementation items(5)-3： Element test verification of the installation procedures[Result]: Element test plan ①
Ascertaining the reference location using a laser scanner[1] Establishing the installation reference line joining the pedestal opening and
the X-6 penetration opening.
[2] The rail installation reference line is established for the cell.
[3] The rail installation position reference line and the installation referenceline are aligned at the time of installation.

Since the work of establishing the installation reference line
joining the pedestal opening and the X-6 penetration opening isimportant work, the method of ascertaining the position is
studied and the viability is verified by element tests.

[Factory][R/B]

Shielding door

Shielding door

Fuel debris
retrieval cellRail installation reference line

[R/B]

Fuel debris retrieval cell

installationreference line

X-6 penetration

installationreference line

Rail installationreference line

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

Rail installationreference line

[2] Establishing the rail installation reference line

[3] Installing at the place
where the rail installation position reference line
coincides with the installation reference line.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project[1) (1) Development of the Method for Installing Access Equipment]

No.72① Installation of large heavy structures(5) Implementation items (5)-3： Element test verification of the installation procedures[Result]: Element test plan ① Overview of the steps for ascertaining the reference location using a laser scanner

Illustration of work
steps

Work
作業
step
ステップ

ス
テ
ッ
プ
図

1. Verification of the state of
1.隔離部屋状態確認
isolation chamber

PCV steel plate
Robot carry-in
chamber

Hatch
isolationchamber
Air-tight
door

CRD opening

Illustration of work
steps

Work
作業
step
ステップ

ス
テ
ッ
プ
図

Hatch
isolationchamber

Target

Air-tight
door

TargetPCV steel plate

R/B wall surface

CRD opening

Hatch
Robot carry-in
isolationchamberchamber
Air-tight
Targetdoor

Robot carry-in
chamber

PCV steel plate

Target

CRD opening

PCV steel plate

Hatch
isolationchamber
Air-tight
door

CRD opening

CRD opening

Robot carry-in
chamber back hatch

Inclined rail for
CRD exchange
X-6 penetration

Robot
carry-inchamberback hatch

Inclined rail for
CRD exchange

Measurement robot
X-6 penetration• Confirming the dust concentration of the robot carry-in
chamber• “Opening” the back hatch of the robot carry-in
・ロボット搬入部屋のバックハッチ「開」
chamber•・計測ロボットをロボット搬入部屋搬入
Carrying-in the measurement robot to the robot carryin chamber
・計測ロボットのケーブル敷設• Laying the cables for the measurement robot
・ロボット搬入部屋内にターゲット設置• Installing the target inside the robot carry-in chamber

5. Installation of 3D scanner
5.3DスキャンをPCV内に設置
inside the PCV

6. 3D scanning of the inside of
6.PCV内の3Dスキャン
the PCV・ハッチ隔離部屋の気密扉「閉」確認• Verifying the air-tightness of the hatch isolationchamber and the robot carry-in chamber・ロボット搬入部屋ダスト濃度確認

TargetHatch isolationchamber
Air-tight
door

Robot carry-in
chamber
CRD opening

TargetHatch isolationchamber
Air-tight
door

CRD opening

Inclined rail for
CRD exchange

Measurement robot
X-6 penetration

Measurement robot
X-6 penetration

Inclined rail for
CRD exchange

penetration
・計測ロボットのX-6ペネ前に走行• Inserting and positioning the 3D scanner inside the・3DスキャナをPCV内に挿入・位置決め
PCV・3Dスキャン（全方位）• 3D scanning (Omnidirectional)

Inclined railfor CRD
Robot
exchangecarry-in
Inclined railfor CRDchamber
X-6 penetration
back
exchange hatch

X-6 penetration

Measurement
robot• “Opening” the air-tight door of the hatch isolation chamber•・ハッチ隔離部屋の気密扉「開」
Placing the 3D scanner at the center of the X-6 penetration•・3DスキャナをX-6ペネセンターに配置
3D scanning (omnidirectional)• 3D scanner (Omnidirectional)

・3Dスキャン（全方位）

7. Pulling out of 3D scanner on
7.3DスキャンをR/B側に引抜き
the R/B side

8. 8.片付け
Clearing

PCV steel plate

PCV steel plate

TargetRobot
carry-inchamberback hatch

Hatch isolationchamber

Air-tight
door

CRD opening

Measurement robot
X-6 penetration

Inclined railfor CRDX-6 penetration exchange

3D scanner•・ロボット搬入部屋のバックハッチ「閉」“Closing” the back hatch of the robot carry-in chamber• Installing the target on the R/B wall

3D
scannerRobotcarry-inchamberback hatch

3D
scanner

・R/B壁面にターゲット設置
surface・3Dスキャン（全方位）Robot carry-in
chamber

3D
scannerRobotcarry-inchamberback hatch

Measurement
Robot
robot
carry-inchamberback hatch

PCV steel plate

PCV steel plate

Robot carry-in
chamber• Traveling of measurement robot in front of the X-6

Details内容

4. 3D scanning of X-6
4.X-6ペネの3Dスキャン
penetration

3. 3D scanning on the
3.R/B側の3Dスキャン
R/B side

PCV steel plate
Robot carry-in
chamber• Confirming that the air-tight door of hatch isolationchamber is “closed”

内容
Details

2. Carrying-in of the
2.計測ロボット搬入
measurement
robot

Inclined rail for
CRD exchange• Pulling out the 3D scanner from the PCV on to the R/B side•・3DスキャナをPCVからR/B側に引抜き
Withdrawing the measurement robot to the robot carry-in
chamber
・計測ロボットをロボット搬入部屋に後退• “Closing” the air-tight door of the hatch isolation
・ハッチ隔離部屋の気密扉「閉」
chamber•・ロボット搬入部屋N
Nitrogen purging of robot carry-in
2置換 chamber

Robot carry-in
chamber
TargetRobot
carry-inchamberback hatch

Hatch isolationchamber
Air-tight
door

CRD opening

X-6 penetration

Inclined rail for
CRD exchange• “Opening” the back hatch of robot carry-in chamber・ロボット搬入部屋のバックハッチ「開」• Carrying-out the measurement robot from therobot carry-in chamber・ロボット搬入部屋から計測ロボット搬出• “Closing“ the back hatch of the robot carry-in chamber・ロボット搬入部屋のバックハッチ「閉」©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.73(5) Implementation items (5)-3： Element test verification of the installation procedures[Result]: Element test plan ① Ascertaining the reference location using a laser scanner and the method of marking the layout[Element test ① Establishment of the reference line marking method]➢ The R/B wall surface (required area), X-6 penetration, and pedestal opening are measured by 3D scanning to obtaincoordinates, and the method for marking the installation reference line for the cell is verified.
• Simple measurement is performed using the 3D scanning method studied, and the coordinate position is ascertained byintegrating the measurement results.
(Refer to the diagram below for the measurement image.)• The installation reference line is marked on the building floor based on the coordinate data, and its accuracy is verified.
3D scanning while the isolation chamber door is
open(Acquisition of data pertaining to Target A and B)

Simulated BSW(Not essential)

Simulated R/B wall surface

PCV simulation

3D scanner(Measurement data C)

Target B

Closing the isolation chamber door andreleasing the air-tight door

Simulated isolation chamber
Simulated air-tight door

Simulated pedestal
opening

3D scanning while the air-tight door is open
(Acquisition of data pertaining to Target A and X6 penetration)
Inserting the scanner into PCV

3D scanning in PCV(Acquisition of data pertaining to X-6 penetrationand pedestal opening)

Simulatedisolationchamber door
3D scanner (Measurement data A, B)

Target A

Illustration of 3D scanning

The relation between R/B wall surface, X-6 penetration and pedestal opening is ascertained interms of coordinates based on the measurement data A, B and C, and the installationreference line is marked on the R/B floor after the isolation chamber is removed (for verifying
accuracy).

Simulated inclined railfor CRD exchange
Simulated X-6 penetration[Supplement]• It is assumed that the isolation chamber is set up based on theassumption 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(5) Implementation items (5)-3： Element test verification of the installation procedures[Result]: Element test plan ② Positioning the cell adapter with the PCV steel plate[Element test ② Verification of whether or not the cell adapter connecting flange can be processed]➢

In order to verify whether or not the cell adapter connecting flange can be processed, the flange is manufactured based on
the data obtained by performing 3D scanning of the simulated bodies, and its installation with the simulated body isverified.
・ 3D scanning of the simulated PCV steel plate is performed, and the data required for designing the shape of the flange isacquired.
・ The cell adapter connecting flange is manufactured based on the measurement data, and whether or not the flange canbe processed is verified by confirming the installation.

Shielding door (simulated)

BSW
BSW opening

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

PCV steel plate(simulated)

Temporaryshielding wall
Pillars in thebuilding

Scanner

Digitalization of the PCV steel plate surface byintegrating multiple data

Shielding door
frame (Simulated)

Designing and processing of the cell adapter
connecting flange

X-6 penetration(Simulated)

Verification of the installation of the cell adapter
connecting flange and the PCV steel plate surface

Building floor[Supplement]* The 3D scanning was performed at a prescribed location and the flange was manufactured based on
those results.

Illustration of the scanning test of the PCV steel plate surface••

1/2 scale simulation
Although studies have been conducted during the existing subsidy projects, as themethod of scanning narrow spaces such as around and under the X-6 penetration,etc. has not been studied yet, it is planned to be studied under 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.75① Installation of large heavy structures(5) Implementation items(5)-3： Element test verification of the installation procedures[Result]: Element test plan ③ Method of remotely confirming the position at the time of carrying-in and installing the cell
adapter[Element test ③ Verification of the insertability of the cell adapter]➢ In order to identify specifications required for remote operation, the cell adapter is inserted in the simulated
body and the workability is verified.

Shielding door
(simulated)

BSW
BSW opening

Temporaryshielding wall

PCV steel plate
Shielding door
(simulated)
frame(Simulated)

Pillars in thebuilding

X-6 penetration(Simulated)

・ The ability to carry in the cell adapter through the BSW
opening /shielding door frame is verified.
① Confirming for interference with the shielding door
frame and the BSW opening② Verifying the ability to carry-in while the X-6
penetration still remains
・ The positioning of the cell adapter with respect to the
PCV steel plate and the shielding door is verified.
・ The gap between the PCV steel plate/shielding door
frame and the cell adapter is verified.

Building floor
Cell adapter

Rail for carrying inand out* The cell adapter is transferred using a generic crane and verified.

Illustration of the work of carrying-in the cell adapter(Note) 1/2 scale simulation(Details of the method of carrying-in the cell adapter are being studied)©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(5) Implementation items (5)-3： Element test verification of the installation procedures[Result]: Element test plan ④ Confirmation test for verifying the installation procedures of the cells, etc.
[Overall verification test]➢ The fuel debris retrieval cell (partially simulated) is installed in the following test equipment used in element
tests ②, ③ for identifying the requirements related to the work of connecting the cell adapter by remote
operation, and the overall structure is verified.
[Test equipment]➢Partially simulated PCV and BSW around the X-6 penetration inside R/B➢ Simulated cell adapter, shielding door, and fuel debris retrieval cell
(Approximately 1m of the length of the fuel debris retrieval cell on the PCV connection side wassimulated.)➢ The plan is to basically simulate to 1/2 scale.

PCV concrete (BSW)PCV steel plate

Shielding door frame

Cell adapter

Fuel debris retrieval cell

Shielding door
X-6 penetration(after cutting)Rail for carrying in the cells©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(5) Implementation items(5)-3： Element test verification of 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 the structure inside the R/B 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. 71, 72, 73)2） Confirmation test on alignment of the cell adapter and PCV steel plate, method of confirming theposition at the time of carrying-in and installation, and verification of the installation proceduresof the cells, etc.
PCV and BSW around the X-6 penetration inside R/B are partially simulated, and the cell adapter,shielding door and fuel debris retrieval cell are simulated (Approximately 1m of the length of the fueldebris 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 theworkability. (Reference: No. 74, 75, 76)
・ 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

No.78(5) Implementation items (5)-3： Element test verification of the installation procedures✓ Level of achievement compared to the goals[Objective]: To verify the viability of the following issues identified in (5)-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) Ascertaining the reference location using a laser scanner and the method of marking the layout
・ Study on the method of ascertaining the reference location has been completed (The layout will bemarked by means of regular marking.)
・ Study of the element test details and test equipment is underway.
2） Method of positioning the cell adapter with the PCV steel plate
・ The method of ascertaining the shape by means of laser scanning is being studied.
・ The method of reflecting the scanning results in the shape of the tip of the cell adapter is being
studied.
3） Method of remotely confirming the position at the time of carrying-in and installing the cell adapter
・ Method of ascertaining the position with respect to the PCV steel plate at the time of carrying-in thecell adapter is being studied.
・ The test piece and the test equipment are being designed.
4) Confirmation test for verifying the installation procedures of the cells, etc.
・ The test piece and the test equipment are being designed.

✓ Future plans
・ The test piece will be arranged for and the test method will be determined (up to September in 2022)©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(5) Implementation items(5)-4： Organizing the required specifications of the equipment for remote installation[Purpose]: Verification of feasibility of the side access method for large scale fuel debris retrieval based on onsite application.
[Objective]: To clearly specify the specifications required of the equipment needed for remote operation basedon 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 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 thetime 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 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.80① Installation of large heavy structures(5) Implementation items(5)-4： Organizing the required specifications of the equipment for remote installation[Result]: Cell adapter installation procedures (Proposed)
Cell adapter

Work step
BSW

1. Advanced preparations(1) Polishing the surface adjoining the PCV wall surface

PCV

3D measurement of the surface adjoining the PCV wall(2) surface

Cell adapter grabbing armb(3) Fabricating the cell adapter(4) Processing the cell adapter connecting flange

PCV

Factorya(5) Connecting the cell adapter and the cell adapter connecting flange

Cell adapter
Welding equipment / tool rack2) Cell adapter connection work
(1) Inserting the cell adapter

Shielding door

Connecting flange(2) Positioning the cell adapter(3) Welding/inspecting the cell adapter① Positioning on the PCV side (a in the figure)
Welding the PCV side and the PCV wall surface (a in the② figure)③ Positioning on the cell side (b in the figure)
Final welding of the cell side and the shielding door (b in the④ figure)⑤ Carrying-in and positioning the fuel debris retrieval cell
⑥ Welding the fuel debris retrieval cell and shielding door⑦

For welding
Robot arm

Inspecting the welded part

Proposed inspection method: Management of execution procedures+ visual inspection + leakage inspection[Issues]

Cell adapter transportation cart

Cell adapter transportation cart andwelding equipment (image)Development of detailed procedures for inserting andinstalling the cell adapter⇓
Establishment of installation adjustment method
considering the possibility of installing remotely andsetting of adjustment margin⇓
Clarification of required specifications of the equipment
for remote installation©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(5) Implementation items(5)-4： Organizing the required specifications of the equipment
for remote installation[Result]: Cell adapter installation procedures （Proposed）

Element test verification of the installation procedures
Element tests on positioning and installing the components*that form the boundary were conducted to identify required
specifications for remote operation (equipment for remote
operation).
*1) Shielding door, cell adapter, large cells

No.81

Shielding door
(Shape simulation)

Fuel debris retrieval cell(Partial simulation)

Cell adapter

Rail(Shape simulation)

Carrying-in andinstallation of cell adapter

Installation of fuel debris
retrieval cell

Illustration of element tests
№
1

2

3

IssuesTest details

Development of detailed procedures for 1) 3D measurement and shape verification of the cell adapter and PCV steel plate
inserting and installing the cell adapter 2）Verification of the method of inserting the cell adapter into the BSW opening
3) Verification of the connection between the cell adapter and BSW/PCV
Establishment of installation adjustment
4) Verification of the workability of welding the cell adapter and PCV steel plate (Manual
method considering the possibility of
welding)
installation remotely and setting of5) Verification of the ability of centering and positioning large cells with respect to the shielding
adjustment margin
door and cell adapter after the large cells are carried in
Clarification of required specifications of 6) Verification of the workability of welding the large cells, cell adapter and the shielding door
the equipment for remote installation(Manual welding)

Verification is carried out by element tests and the required
specifications of the equipment for remote installation are identified.
©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(5) Implementation items (5)-4： Organizing the required specifications of the equipment for remote installation[Result]: Organizing the requirements concerning the cell adapter installation cart with respect to the carrying-in
and installation work steps
Work step

Requirement

1. Advanced preparation(1) Polishing the surface adjoining the PCV wall surface

Should be able to polish the PCV steel plate by means of remote operation
Should be able to remotely measure the PCV steel plate surface and the BSW opening with reference to theexisting layout marking line(2) 3D measurement of the surface adjoining the PCV wall surface(3)(4)

Manufacturing the cell adapter
In-factory work

(5)

Processing the cell adapter connecting flange

Processing the flange based on the results of the measurement done in (2)Connecting the cell adapter connecting flange to the cell adapter

2. Cell adapter connection work
(1) Inserting the cell adapter

Should be able to remotely carry in the cell adapter without any interference up to the reference location(2) Aligning/welding/inspecting the cell adapter① Alignment of the cell adapter on the PCV side (a in the figure)② Gap measurement③ Welding of the PCV side of the cell adapter and the PCV wall surface (a in the figure)④ Alignment of the cell adapter on the shielding door side (b in the figure)

Should be able to remotely move up to the prescribed location based on the 3D measurement results
Should be able to remotely measure the perimeter of the gap with the PCV steel plate while holding the cell
adapter
Should be able to remotely weld the cell adapter and the PCV steel plate while holding the cell adapter⑥ Welding the shielding door side of the cell adapter and the shielding door (b in the figure)

Should be able to remotely move up to the prescribed location based on the 3D measurement results
Should be able to remotely measure the perimeter of the gap with the shielding door while holding the cell
adapter
Should be able to remotely weld the cell adapter and the shielding door while holding the cell adapter⑦ Inspection of the welded portion

Should be able to remotely perform VT inspection of the welded part

⑤ Gap measurement② The required functions are classified based on the requirements consolidated, and thespecifications are consolidated accordingly.
Function① Ease of travelingSpecification
Traveling speed○ m/min or more

Ability to climb

Should be able to climb a gradient of ○ °② Operability③ Ability to be positioned (accuracy)④ Safety⑤ Ease of maintenance⑥ Resistance (Radiation resistance and useful life)

Cell adapter
Shielding door

Welding equipment

Cell adapter
Grabbing arm
b

PCV

PCV
Under examinationaCell adapter
Cell adapter transportation cart

Connecting flange

Illustration of cell adapter installation cart
©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(5) Implementation items(5)-4： Organizing the required specifications of the equipment for remote installation✓ Contribution of the results towards the reflection destination
・ Contribution to substantiate the procedures for installing access equipment inside the R/B for the side
access method.

✓ Analysis from the viewpoint of on-site applicability
・ When the structure inside the R/B of Unit 3 and test piece are simulated, although the scale is reduced to
1/2 and the weight is not simulated, the small size makes handling easier, and as the environmental
conditions (shape of the BSW opening / PCV steel plate, etc.) that are required for installation are
simulated, it becomes easier to verify workability at the site. (Reference: No. 76, 80, 81)
・ The on-site work procedures are studied, and the results are reflected when the on-site work is
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.84(5) Implementation items(5)-4： 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 basedon 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) Organizing 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[Achievement status]
1) Clear specification of the cell adapter carrying-in and installation procedures・ The studies on the overall procedures have been completed, and installation procedures are being
studied in detail.
・ Study of the element test details and test equipment is underway.
2) Organizing the requirements concerning the equipment with respect to the carrying-in and installation
procedures・ The basic required specifications are being clarified from the overall procedures.
3） Clear specification of the requirements concerning the equipment based on the results of element
tests
・ Planned to be reflected after implementing the element tests.

Future plans
・ The test piece will be arranged for and the test method will be established (up to September in 2022).

©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) Summary➢ The structure was detailed focusing on the boundary (connected parts, assembled parts andinstalled parts) of the cell adapter, shielding door and fuel debris retrieval cell that form theaccess equipment.
➢ The access equipment and other fuel debris retrieval equipment cells need to be installedaccurately in a straight line between the pedestal opening and the X-6 penetration opening, inorder 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 installation accuracy.
➢ As a part of the study for enhancing throughput, the work carried out inside the cells wasdetailed 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 ofwhether or not insertion is possible, and overall structure) for determining the policy for
responding to the issues and for verifying it are being designed.
➢ Since the work of installation will be carried out under high radiation dose environment, thecell adapter will need 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 is being
created based on a structure that was substantiated.
©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(7) Development Schedule
4
Major milestones[Legend] Plan:

FY2021

Study items
5

6

7

8

9

10

No.86

Actual:FY202211

12

MRI InterimInterim
ReportReport
▼
▼

1

2

3

4

5

6

7

MRI Interim Report
Interim Report
▼
▼

8

9

10

11

12

MRI
InterimInterim
ReportReport▼1

2

3

MRI Final
FinalReportreport▼Substantiation
thecarried
workout
carriedout
Substantiationof theof
workinside thefuelinsidedebrisretrieval cell(a) Detailed study ofthe structure of theaccess equipment(b) Study on
detailing of steps
involved ininstalling theaccess equipment(c) Element test
verification of theinstallation
procedures

the fuel debris retrieval cell

Required
Required installation
installation
accuracy
accuracy

IDR (Structure of theaccess equipment)

Detailed examinationof
Detailed
examination
structureof structure
Assumption of failuremode of theOrganization of installation conditions
components

Specification of installation equipment and tools
Review as appropriate

Underreview

Risk assessment /Detailing of installation
Study ofsteps
response

Specification of installation procedures

Organization of installation
conditions
Detailing of installation procedures
Study of element test plan
Specification of remote installation equipment andinstallation tools
Specification of installation procedures
Manufacturing of element test equipment

Element test plan (brief study) Element test plan (detailed study)(d) Detailing of thework carried out
inside the cells of thefuel debris retrieval
equipment(e) Creation of a report on
installation of large heavy
structures

Element test
Preparation forelement tests

IDR (Element test plan)

Substantiation of the work carried out inside and outside the fuel debris retrieval
cell and study on cell structure
Manufacturing of element test equipment Preparation
Assumption of failure mode of the components

for element
tests

Element test

Risk assessment / Study of response

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.87
Solicitation items are listed.

② PCV connection sleeve installation and welding by remote operation
Studies have been conducted related to ensuring air-tightness of the connected parts foraccessing the inside of the PCV for the purpose of further increasing the scale of retrieval offuel debris and reactor 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 and installation conditions that include high radiation and confined
spaces, etc., thereby securing the confinement 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 devices andequipment, and procedures 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 aseries of operations such as welding procedures, inspection and maintenance by remote
operation, including the development of methods considering accuracy of installation byremote operation, remote welding equipment and required tools, pre-processing such aspolishing before welding, will be studied. Thereafter, verification tests using simulated test
pieces will be planned and implemented, and the welding efficiency and viability of therequirements 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]② PCV connection sleeve installation and welding
by remote operation

No.88
Additional

増設建屋
Building

Overview of the 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

Access tunnel
アクセストンネル[Overview of the method]① The access tunnel was installed by delivering it from outside the R/B.
② The load was supported by the R/B wall and the BSW.
(Note) Connecting the access tunnel to the equipment hatch is being planned (common for Units 1 - 3)
[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]② PCV connection sleeve installation and welding by remote operation

No.89

Development results related to the access tunnel achieved so far and correlation with this project are indicated below.
Biological shield opening

Method & Systems Upgrade (Implemented in FY2017-18)

Access tunnel[Verification of the feasibility of the method (conducting element tests
related to shape, dimensions, scale)]➢
Delivery of a tunnel part➢
Delivery of the curved surface tunnel through the narrow opening➢
Remote work monitoring, positioning accuracy

DeliveryAccess tunnel (actual
outer appearance)

Location of R/B outer wall
Access tunnel

SleeveDisplacement 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

Slide part
Load support point

Load support
point

Approx. 1800mm

Displacement
absorption
mechanism

Ensuring Safety (Implementation in FY2020-21)

Implemented in this project[Verification of feasibility looking ahead at the actual
equipment]➢
Study of the method of remotely installing and welding
the sleeve (Verification at full scale)➢
Addition of shield and disassembly of shield plug

[Verification of feasibility through testing]➢
Delivering heavy weight objects (Verification of theslide part)➢
Displacement absorption mechanism (Verification ofquantity of leakage)]
Outsourced to TEOCO HD (Implemented in FY2020-21)

Items to be studied in future➢

PCV connection
sleeveStudy of developmental challenges identified during engineering andtechnical development, etc.

[Study of the concept of the equipment for
remotely installing the PCV connection sleeve]➢
Selection of proposal for remote installationWeldingof sleeve➢
Conceptual design and identification ofissuesPCV(equipment hatch)©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.90[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)
Illustration of the PCV connection⚫ Selection of abrasive
sleeve installation (Unit 3)⚫ Study of grinder (Implementation of trial 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

Flat plate (t=12)

Flat plate (t=90)✓ Stacking method✓ Welding position✓ Heat input for welding✓ Welding gap

Element test
✓ Welding gap(Equipment similar to theactual equipment)

Full scale mock-up tests
✓
✓
✓
✓
✓

Series of procedures
Process management
Inspection (Fluorescent PT)
Verification of welding strain
Cold crack measures

Implemented©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.91[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 thework environment (radiation dose, etc.).
•
The method of accurately installing the sleeve by remote operation is studied, and a remote welding method
considering the remote installation accuracy (gap) is established.
[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 devices and equipment, 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 areconsolidated, 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 coverinstallation equipment[Expected outcome]•
Presentation of a method for remotely installing the sleeve•
Presentation of a series of welding procedures related to the sleeve
Polishing and inspection 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]② PCV connection sleeve installation and welding by remote operation

No.92[Implementation details]
Feasibility of remote operation is verified by remotely carrying out operations from installing the PCV connection sleeve, pre-processing,welding, up to inspection and repairs (some operations were not carried out remotely).
PCV connection sleeve installation

PCV connection sleeve welding

Installation and welding of the main bodyof the AT*3

Cutting and removal of equipment hatch
door

Cutting lines (Lattice)

PCV connection sleeve installation equipment

PCV
connection
sleeveEquipment hatch

Main
body
of
Work steps
AT

Welding machineWork steps

Work steps

Work steps①

Delivering the sleeve①

Welding the sleeve and the equipment hatch①

AT main body delivery and joining with thesleeve①

Operating the additional building②

Installing the sleeve on to the equipment
hatch*1②

Installing and welding the scaffolding seal
cover*2②

Welding the AT and sleeve②

Installing the equipment hatch door
cutting and removal equipment③

Verifying the installation status of the sleeve *1③

Welding of the equipment hatch door part
(existing seal)③

Polishing the welded part③

Cutting the equipment hatch door④

Removal of part of the equipment hatch
scaffolding④

Polishing the welded part④

Inspecting the welded part (VT/ fluorescentPT)④

Collecting and removing the cut piecesof the equipment hatch door⑤

Blasting the welded part⑤

Inspecting the welded part (VT/ fluorescentPT)⑤

Pressure resistance test

[Issue]⚫ Positioning the sleeve and the equipment
hatch[Issue]⚫ Remotely welding the sleeve and theequipment hatch⚫ Method of inspecting / polishing the welded
part[Issue]⚫ Remotely welding the sleeve and main body of AT⚫ Method of welding / inspecting the welded part
⚫ Pressure resistance testing method(Implementation through actual equipment
engineering)*1: Work steps ② and ③ are not implemented in continuation. The results of sleeve installation test are reflected in the welding test.
*2: Installation is not done remotely.
*3: Access Tunnel

Scope of study[Issue]⚫ Method of cutting equipment hatch(Implementation through actual equipment
engineering)

Scope of verification
by means of the test

©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.93[Remote installation
study procedures][Implementation details][Remote welding
study procedures]
Robot<Remote installation of PCV connection sleeve>
The PCV connection sleeve installation equipment is test manufactured
and the installation accuracy is verified at full scale.

Scaffolding seal coverinstallation equipment

Polishing and inspection
equipment, etc.

Required accuracy

Remarks

Selection of remote
installation equipment

Study of welding related
equipment

Designing of remote
installation equipment

Designing of welding
related equipment

Manufacturing of remote
installation equipment

Manufacturing of welding
related test equipment

Test implementation of
remote installation

Preliminary test

As it has been confirmed during the FY2019-20

The gap between the PCV connection subsidy projects that a gap of 20mm or less can besleeve and the equipment hatch shell welded, the sleeve installation accuracy
requirement is set at 20mm or less.
must be 20mm or less.
(Target value: 7.5mm)

However, considering the on-site workability, as it
is desirable to have a gap of 7.5mm or less, thetarget value is set at 7.5mm.

<PCV connection sleeve welding>
The assumed welding gap is determined using the results of the PCV
connection sleeve remote installation test, and welding test is
implemented at full scale. After welding, non-destructive inspection iscarried out to verify the soundness of the welded part.

Determination of location before
starting the work of welding theequipment hatch and sleeve

Verification of remote
installation accuracy
Determination of
welding test conditions

Implementation of
welding test
©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: (a) Remote installation

No.94[Implementation details]
Implementation items

Implementation details

Selection of proposed remote installationequipment(Consolidation of preliminary review results)

Conceptual study is conducted, remote installation equipment is selected from multiple proposed
equipment, and conceptual design is developed. The delivery equipment is selected based on the
results of conceptual design.

Designing of remote installation equipment

Basic design of the equipment is developed. In addition, back-up proposals are studied andimplemented.

Manufacturing of remote installation equipment
Test implementation of remote installation
Verification of consistency with the results of thewelding element test
(Proposal 1)
Forklift method

The scope of simulation (area required for verifying the positioning) is established, and the section
around the equipment at the tip is manufactured.
Installation test is conducted using a simulated sleeve to verify the installation procedures andaccuracy.
Consistency with the gap that can be welded according to the welding element tests conducted up
to FY2020 is verified. If the target is not achieved, back-up proposals are examined deeper, andverified as required.

(Proposal 2)
Traveling rail method(Proposal 3)
Integrated delivery method(Proposal 4)
Rail delivery method(Proposal 5)
Boom method(Note) The figure illustrates Unit 1

The installation accuracy with respect to the simulated equipment hatch andsimulated biological shield (simulated BSW) is verified.
©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: (a) Remote installation[Consolidation of preconditions]

12000 up to the reactor core

A
No

Items

Preconditions

1

TargetUnit 1: Installed from thenorthern side
Unit 2: Installed from thesouthern side
Unit 3: Installed from thesouthern side2

Load on the R/B floor

Approx. 4.9 ton/m2

3

Dimensions of theassumed R/B
opening

Unit 1: W5060×H6000mm
Unit 2: W6300×H6100mm
Unit 3: W6100×H6100mm

4

Distance from theR/B wall to theequipment hatch

5Interfering objects
inside and outside
the Reactor Building

6

BSW opening (floor
surface)7

Equipment hatch
shell

Unit 1: Approx. 16m
Unit 2: Approx. 18m
Unit 3: Approx. 18m

No.95

Remarks
Installed from the same
opening as the accesstunnel main body in allunits

A
BSW opening(front view)

Cross-section A-A

PCV connection sleeve weight
Unit 1: Approx. 25ton
Unit 2: Approx. 40ton
Unit 3: Approx. 400ton
PCV side

All must be removed.
Must be flat and at the samelevel as the first floor

H3000
W3830

Rust, etc. must be removed.

Access tunnel side

D2230

Bird's eye view of the PCV connection diagram (Unit 1)
Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

©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: (a) Remote installation

No.96[Selection of remote installation equipment]
Proposal 3 and 4 were 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 othe proposals in terms of the schedule aswell. → Proposal 3 is selected.
(Proposal 3) Integrated delivery
method(Proposal 1) Forklift method(Proposal 2) Traveling rail method

Building floor load
capacity(Unit 3: 4.9tm2)△(Needs to be analyzed)x(Load capacity of the footpart at the tip 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

AbsentRegular machine elements

Absent Track record of retracting of(Access tunnel main body mock-up)

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.

AbsentAbsentPresent (Continuous air supply in theevent of an emergency)

✓

✓
Major

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 4) Rail delivery method(Proposal 5) Boom method✓(As it is cantilevered it does not come in contact with the floor
surface.)△
Load from an air caster(Manufacturing) Possible.
(Method) Possible. Mock-up of thedelivery has been implemented. The
preceding and subsequent processes
need to be considered.

Grave issues

Present (Interference with the pillars)

Present (Load capacity)

Applicability to otherunits

x(Interference with the pillars)(Except building floor load capacity)

Impact on schedule

Minor

Major

Medium

Evaluation

x

x

✓

✓

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

boom is present)✓(Except building floor load capacity)

Minor

x
✓
©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: (a) Remote installation[Conceptual design_full view (Proposal 3)]

No.97(Note) The figure illustrates Unit 3

Counter weight (CW)

Main frame

PCV connection sleeve

Delivery equipment

Maximum height ofequipment(Approx. 4900)

Equipment at the tip

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

©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: (a) Remote installation

No.98[Conceptual design_outline of installation steps]⚫
⚫

Advanced preparations and equipment installation are tasks carried out directly by humans (not remote operations).
Delivery is carried by a remote operation.
Layout marking and other markings play an ancillary role in delivery. Final verification is carried out using camera or
measuring instruments.
Step

Item

Overview

Work

1

Advanced preparations

The required layout, etc. is marked 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 meansof the equipment at the tip, and fine adjustments are made while
confirming the gaps in the entire periphery by means of a camera, etc.

Remoteoperation

5

Seating

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: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

©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: (a) Remote installation

No.99[Conceptual design_outline of delivery steps]⚫
⚫
⚫
⚫

①： Advanced preparations②： Delivering the sleeve using the delivery equipment (jack)③： Transporting it to right in front of the BSW opening using the delivery equipment and rotating unit.
④： Transporting it to its final position using the extension/oscillation unit, and seating and fixing it(Note) The figure illustrates Unit 3① Before delivering② Delivering in a straight line
(Delivery (1))③ Rotating the PCV connection
sleeve (Delivery (1))

④ Inserting the sleeve(Delivery (2))

1. Ground maintenance
2. Installation of the delivery
equipment
3. PCV connection sleeve
installation
4. Installation of main frame andcounter weight

1. Delivery inside the R/B (delivery
equipment)
2. Installation of counter weight(subsequently)(Delivering the PCV connection
sleeve up to a position from where
it can be rotated)

1. Rotating the PCV connection
sleeve (rotation unit)
2. Delivery up to the vicinity of the
BSW opening (delivery
equipment)

1. Insertion of PCV connection
sleeve (extension unit)
2. Fine adjustments (extension
unit / oscillation unit)
3. Seating (hoisting unit)
4. Fixing (PCV connection sleevejack)
5. Withdrawal (delivery equipment/ equipment at the tip)

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).
©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: (a) Remote installation

No.100[Conceptual design_positioning method / adjustment shaft]No.

Direction①

Alignment mechanism
Delivery equipment

X②① Pivot③④

Rotating unit③

Y

Extension unit④

Zθ

Oscillating unit⑤

Z

Hoisting unit②①

PCV connection sleeve② Rotating unit

④ Axis of oscillation

Z direction⑤③ Extension unit
⑤ Hoisting unit
④ Oscillating unit

(Note) The figure illustrates Unit 3
Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

©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: (a) Remote installation

No.101[Review of remote installation equipment]
The mass of the PCV connection sleeve was calculated. As it turned out to be lighter than the results of the preliminary
review, the target delivery height (height of delivery equipment + jack up) was set at 4000mm which is the height at thetime of access tunnel delivery. The remote installation equipment was reviewed, and it was found out that a height of
4000mm or less can work.
(Frame)HeightreducedTip frame Approx. 27ton
PCV
connection
sleeveRotating unit

Rotating unit

(Rotating unit)
Large rotating
bearing→ Shape of sleeve
Extension unit

Oscillating unit
Hoisting unit
Oscillating unit

Equipment at the tip
during the preliminary review

Extension unit

Hoisting unit

(Hoisting unit)
Guide roller→ Linear guide©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: (a) Remote installation

No.102[Schematic view of remote installation equipment]

Maximum height of equipment

Maximum height of equipment(Approx. 3800)

Before improvement: approx. 4900mm
After improvement: approx. 3800mm©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: (a) Remote installation

No.103[Illustration outlining 3D measurement]
The measuring arm is installed at the tip of the remote installation equipment, and 3D measurement isperformed. Operating instructions are given based on the results of 3D measurement for operating the
remote installation equipment.
Opening

Opening (Front view)

Delivery equipment

Equipment at the tip
Joining part

Equipment hatch door

PCV connection sleeve

Motor control signal, LS signal
Inserted

Measuring arm

Composed of 4 shafts:
rotating, shoulder, elbow
and wrist

Jack NJack 1

Composed of 4 shafts: forrotation, extension, oscillationand hoisting<Measuring arm
specifications (proposed)>
Maximum
reach
2000mmIllustration, laser, mirror control
signals, camera control, lights

Motor control signal, limit switch signal

Scope of movement J1:±180°
J2: -90 to 60°
J3: 0 to 180°
J4: ±180°©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: (a) Remote installation[Camera arrangement plan]◼ Use of cameras / lights• Camera / lights ①② Comprehensive view and for verification at the time of passing through the R/B opening (As there
is no delivery in the case of mock-up, cameras are not installed.)• Camera / lights ③④ Verification of the positional correlation between the opening part in the vicinity of the equipment
hatch opening and the AT sleeve
Verification of the clearance of the opening and AT sleeve at the time of insertion• Camera / lights ⑤ Verification of operation of the lift cylinder at the time of installing the AT sleeve• Camera / lights ⑥⑦ Verification of the status inside the opening part, and verification of the status of the measuringarm• Camera / lights ⑧ 3D measurement, and verification of the joint(Camera ④A)

Camera ③A

Lights ④A

Lights ③A

Camera ⑥

No.104

Lights ⑧
3D sensor
Camera ⑧

Lights ⑥

Camera ⑦
Lights ⑦

Lights ④B

Lights ③B

Camera ④B

Camera ②A(Camera ③B)
Camera ① A

Lights ② A
Lights ①A

Camera ③A(Camera ④A)
Lights ③A

Lights ③B
Camera ⑤

Camera ③A

Camera ①B

Lights ⑤(Camera ③B)

Lights ⑦

Lights ①B

Lights ④A

Lights ④A

Camera ⑥(Camera ④A)

Lights ⑥

Camera ⑦

Lights ③A
Lights ③B

Camera ③B©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: (a) Remote installation

No.105[Arrangement of cameras]
The plan is to perform measurement by means of 3D measurement, but every hold point is planned to
be visually (camera) confirmed as well.
Objective

Outline specifications

Remarks

For comprehensive view and for verification at thetime of passing through the R/B opening

PTZ, Collar

2 to 4 units

Verification of the positional relationship between theequipment hatch opening and the PCV connection
sleevePTZ, Collar

2 to 4 units

Verification of the operation of the hoisting unit

PTZ, Collar

1 units

Verification of the status inside the BSW opening partand the status of the measuring arm

PTZ, Collar

2 units

3D measurement (auxiliary), and verification of theclearance of target position

PT, Monochrome

1 unit(Camera with 3D sensor)(Note)
・PTZ：Pan tilt zoom type, PT: Pan tilt type・ The number of units and specifications are likely to change depending on
the designing progress and test results.
©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: (a) Remote installation[Implementation details]
Step*

Items to be verified

No.106

・This plan is likely to change depending on the progress in designing.
Implementation details

Items to be monitored,measured and recorded

Criteria

Verification through studies and tests

3
4

Verification of visibility of cameras, etc.

The installation location and visibility of the cameras at each step arestudied and verified.

➢ Camera image➢ Remote work should bepossible based on theimages form the camera

3
4

Verification of detailed procedures

The installation procedures are studied in detail, the criteria formoving on to the subsequent step are compiled and verified by tests.

➢ Stroke, etc. of the jack(Details will be studied in
the future)➢ Remote work should bepossible by following theprocedures studied.

➢ Installation accuracy➢ 20mm or less(Target: approx. 7.5mm or
less)Serves as input for thewelding test.

3
4

Installation accuracy

Installation accuracy is verified using a simulated PCV connection
sleeve.
(Verification of stand-alone performance of individual units)

Only studies were conducted for the following

1

Verification of installation target

The method of verifying the current status of the equipment hatchshell and BSW, and the method of reflecting the shape after
verification are studied.

4

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 or less)② Estimating the gap

5

Method of detecting seating

The method of detecting that the PCV connection sleeve has been
seated on the BSW is studied, and verified.

6

Verification of the fixing method

The procedures for fixing the PCV connection sleeve on to the BSW
are studied in detail.

－* Refer to Page No. 98 for the steps.
©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: (a) Remote installation

No.107[Scope of manufacturing for the mock-up test (under planning)]
Scope of excavation

Opening

Scope of excavation

Approx. 27ton x 7

Approx. 19ton x 5

Opening

Approx. 55ton

Center of gravity of the delivery frame
PCV connection sleeve

The test equipment is madeup of the mechanicalequipment within the redframe, BSW opening andequipment hatch.

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

No.108② PCV connection sleeve remote installation and welding: (b) Welding[Implementation details]
Implementation items

Implementation details

Specification of process management

The management items such as the position of the torch while welding, etc. and management method are specified,and verified during the welding test.

Study of welding related equipment

The welding equipment (with improved shieldability), tool box, maintenance equipment (polishing), inspection
equipment (fluorescent PT / inspection of dimensions) are studied.

Designing of welding related equipment
Manufacturing of welding related test equipment
Preliminary tests
Determination of welding test conditions

Implementation of welding test

(Only studied) Study of non-destructive
inspection method

Illustration of PCV connection sleeveremote welding test
(Before equipment installation)

Detailed design of the equipment studied above is developed.

The test equipment is manufactured.
Unit test or performance verification tests are conducted.
The default gap is determined based on the PCV connection sleeve installation test.
The following items are verified.
Welding of detached parts (remote), welding of irregular gaps (remote), inspection of welded part (VT/FluorescentPt)(remote), polishing of welded part (remote), verification of on-site workability (to the extent possible)
Also, process management during welding is carried out and items to be verified at the time of actual implementation
are consolidated.

The non-destructive inspection methods (volume inspection in particular) are investigated and studied.

Illustration of PCV connection sleeveremote welding test
(After equipment installation)

Illustration of welding(Note) The scope of simulation is planned to be
specified in the future.
©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 remote installation and welding: (b) Welding

No.109[Results up to FY2020]
During the element tests conducted in FY2019-20, it was confirmed that a gap of 20mm or less canbe 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 cracks
Cold cracks
Welding of thick plates(Concerns about cold cracks)

Fluorescent PT

These issues were studied and full scale simulation 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]② PCV connection sleeve remote installation and welding: (b) Welding

No.110[FY2021-22 Implementation Details (Issues consolidated in FY2020)]
No.

Source studied and verified(Issues identified during the FY201920 subsidy projects)

Study / verification items

Overview of studies to be conducted in FY2021-22①

Joining defects

Specification of process management

The actual work will be carried out remotely, and the camera visibility will be limited
as well. Hence, the torch positioning and angle, etc. need to be verified by means ofa mock-up. What exactly needs to be verified will be specified.

②

Formation of oxides

Study of small welding head
(Improving shielding capabilities)③－１

Concerns about cold cracks

Study of tests on cold cracks③－２

Concerns about cold cracks

Method of preheating④

Need for remote inspection method

Study of inspection method other than
fluorescent PT⑤

Vertical downward welding(Items that are not issues but need to bestudied 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 wereconsidered verified since vertical downward welding can be substituted by vertical
upward welding. However, it could be possible that the work efficiency is better in thecase of vertical downward welding depending on the welding procedures. Firstly, theneed for vertical downward welding will be clarified by studying the procedures, etc.

⑥

Occurrence of false defects(Items that are not issues but need to bestudied in response to test results)

Applicability of the selected abrasive toactual environment

The applicability will be studied and evaluated based on the data obtained during thissubsidy project.

Formation of oxides was not observed in tests conducted by setting conditions.
Controlling the occurrence of oxides and reducing the frequency of polishing as
much as possible by optimizing the gas nozzle, will be studied.

Method of verifying cold cracks prevention when there is no preheating by means oftests (T shaped coupling, etc.), and the welding method will be studied.

The method of preheating the equipment hatch (partial or full) will be studied.
(Not applicable if ③-1 can be implemented)

Methods for remote inspection will continue to be studied.

©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 remote installation and welding: (b) Welding

No.111[Consolidation of issues, etc. in each step] (Including issues consolidated until FY2020)
Step

1

2

3

4

Items

Advanced preparations

Welding

PolishingInspection

StudiedTested/verified

Method of removing scaffolding considering post-processing (welding)－－

Study of rust removal (blast) equipment－*－

Study of scaffolding seal cover installation equipment－*－(1) Specification of process management〇〇(2) Improving shielding capabilities and downsizing〇〇(3) Study of preheating method and working method〇〇(4) Study of welding procedures (stacking procedures, etc. for irregular
gaps)

〇

〇

Study on polishing machine and on the polishing guidelines〇〇(1) Study of fluorescent PT equipment and on inspection conditions(fluorescent agent blast pressure, etc.)〇〇(2) Study of inspection method other than fluorescent PT (includingorganizing the required inspections)〇〇(3) Verification of the accuracy of dimension measurement (by means of
the touch sensor of a robot)〇〇

Issues or 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 accesstunnel main body)－－Note) The items with “－” will be implemented during actual equipment engineering* Studies conducted up to FY2020.
©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 remote installation and welding: (b) Welding

No.112[Specification of process management]
There were conditions wherein joining defects occurred during the element tests. The actual work is carried out
remotely, and the camera visibility is limited as well. Hence the torch posiioning and angle, etc. are verified by tests.
Guideline for welding Gap G
Equipment
hatch

AT Sleeve

Equipment hatch

Required leg length
Appropriate gap(δ) target② Bridge welding① Underlaying fillet welding① Underlaying fillet welding

Required leg length② Bridge welding③ Leg length welding<Welding steps>③ Leg length welding

Example ofjoining defects① Underlaying fillet welding: Fillet welding for filling gap G② Bridge welding: Welding for joining the underlaying fillet welding and the equipment hatch③ Leg length welding: Fillet welding for meeting the required leg length

Welding position: Vertical upward
Gap: 7.5mm©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 remote installation and welding: (b) Welding

No.113[Specification of process management]
Items to be managed in each process are verified by tests and substantiated.
Underlaying fillet
Gap

SleeveEquipment hatch shell

Bridge welding
SleeveEquipment hatch shellGap

1 layer 1 pass a

Gap
depth

1 pass

1 layer 2 passes b

1 layer 3 passes c・・↓

Note: Same in the case of leg length welding
No.

Management items (proposed)

1

Position of electrode (Target position for
touch start)

2

Target angle of electrode3

Welding trajectory

4

Welding conditions (scope)

Items to be managed in each step are verified bytests and substantiated.
©International Research Institute for Nuclear DecommissioningNo.114
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[Study of small welding head (Improving shielding capabilities)]

Since formation of oxides was observed in some of the tests conducted using a small welding head,
the formation of oxides is controlled by studying the gas nozzle and the secondary shield.

OxidesGas nozzle

Small welding head

Element test results(Vertical upward gap G 20mm)

The gas nozzle and secondary shield are studied and verified by welding tests.

©International Research Institute for Nuclear DecommissioningNo.115

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[Study of welding torch]
The formation of oxides is prevented by creating inert gas atmosphere in the vicinity of the molten
metal on the welded part by installing an outer gas cup (secondary shield) at the distal end of thewelding torch.
Angle adjustment plate

Tool changer
Positioning pin
Shock sensor

Outer gas cup
TIG torch

Wire nozzle
Welding monitoring camera unit
Wire positioning slide©International Research Institute for Nuclear DecommissioningNo.116

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[Study of welding torch]An extension bracket isadded besides the secondary
shield considering accessibility.
Interfering objects are
confirmed by means of 3D
simulation.

Welding head being studied

Studies conducted until FY2020<<Part added>>
Extension bracket(with angle adjustment
functionality)* Added considering
accessibility<Part added>
Secondary shieldConfirming for interfering objects bymeans of 3D simulation©International Research Institute for Nuclear DecommissioningNo.117

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[Study of tests on cold cracks / Study of preheating method]
Since thick plates are welded, there are concerns about cold cracks. Preheating method andworking method are studied.
Welding of thick plates(Concerns about cold cracks)With preheating

Study of the method of partial preheating
Heating using non-fillers
Issue: Study of whether or not sufficient heat can beprovided.
→ Element tests will be conducted and the results will
be reflected in the welding procedures.
Study of the method of partial preheating
Study of high frequency induction heating, burner, etc.
Issue： Study of handling by means of robots, etc.

Without
preheating

Studied(Some element tests are planned
to be implemented.)

Study of working method
Study of temper bead technique or other welding methods
Issue: Discrepancy with standards

Studied and tested.

Acquisition of evidence through tests showing that
there is no breakage
Implementation of tests prescribed in JIS, etc.
Issue: The content of actual material and machinery is
unknown.

Studied as required.

The most appropriate measures are
selected considering on-site workability.
©International Research Institute for Nuclear DecommissioningNo.118

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[Study of preheating equipment]
A small high frequency induction heater that can be mounted on the robot as well, is being considered as the preheating
equipment. A demonstration of the high frequency induction heater was conducted to verify its applicability. The test result
showed that it has sufficient heating capability.
Model
Output capacity
Rated input
voltage3-phase 200/220V

Rated frequency

Small high-frequency induction heater

Rated input

Approx.36kVA

Rated current

Approx.100A

Material used: Thickness 30[mm] (carbon
steel)
Remote operation speed: Approx. 750[mm/min](Specifications of the demo unit)
Power supply used: 30[kW](Actual welding speed: 60 to 100 [mm/min])

INV. Output current
Oscillating frequency
INV. Output
voltage

Control system
Rated utilization
Cooling system

Radiator system, forced water cooling

Cooling capacity
WeightDimensions

Demonstration being
conducted

Approx. 180kg
500mmWx700mmDx1060mmD(including castors)

Issues・The total weight is approx. 35kg including
the weight of the heater which is approx. 7
to 10kg, and the weight of the welding
equipment which is approx. 25kg. The
conveyable weight of the robot is 50kg.
However, considering momentum, theweight needs to be reduced.

Power supply specifications©International Research Institute for Nuclear DecommissioningNo.119

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[Study of inspection method other than fluorescent PT]
The fluorescent PT method is being considered for inspection. Firstly, the inspections that are
required as per standards are consolidated, and desk studies on remotely conducting the required
inspections are carried out.
General welding inspection
Types of general welding inspections

Generally called “Color check”, it is widely used for detecting cracks etc. opened up on the surface of theobject being inspected. It is a method that makes micro defects on the surface, which are difficult to detectby means of visual inspection, visible.

Penetration test
(PT)

Magnetic-particle test
(MT)

Details

Surface
inspection

When a magnetic substance is magnetized, magnetic flux leaks if there are defects on the surface or in thevicinity. This is a method for identifying the location and form of defects by detecting leakage of magnetic
flux using magnetic particles (fine dust of ferromagnetic substances).

Eddy current test
(ET)

This is a method in which the presence of defects or the change in their form is inspected by applying amagnetic field that changes over time to the test piece by means of a coil through which AC current
passes, and using the changes in the excess current generated in the conductor.

Radiographic Test
(RT)

This is a method in which the presence of defects and their form are detected using the ability of radiation
to penetrate substances and the ability to expose camera films, by exposing the test piece to radiation, anddeveloping the difference in intensity of radiation after it has passed through the test piece into a grayscale image.

Volumetricinspection
Ultrasonic Test
(UT)

When there are internal defects in the test piece, the ultrasonic waves (frequency higher than 20,000Hz,
which is the upper limit of the audio-frequency range of humans) incident upon the test piece either get
reflected or scatter depending on the defect. This is a method in which this phenomenon is used to inspect
the presence of internal defects and their form.

Note: Testing methods other that those mentioned above (Alternating current potential drop, etc,) will be studied as required.
©International Research Institute for Nuclear DecommissioningNo.120

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[Study of inspection method other than fluorescent PT]
Design and Construction Standards*1/ Welding Standards*2

Class 3 piping (Overview)
Standard No.

Explanation

Design of the welded part
(Design/Construction Standards:
PPH-4000)

PPD-4010(5)b.

The welded part at the joint of the seal welding should be acontinuous fillet weld.

Groove surface

N-7030

Removal of harmful foreign material

Strength, etc. of the welded partN-7040Equivalent to or more than the strength of the base metal

Non-destructive testing andmechanical testing of the welded part
Finishing of the joints

N-7050/7100
Table N-X050-1
N-7080

MT or PT
Should be smooth.

Post-weld heat treatment

N-7090
Table N-X090-1, 2

Required when the thickness of the base metal is >38mm(Can be substituted with preheating)

Mechanical testingN-7110
Table N-X110-1

Not required (depending on the classification of the joint)

Pressure resistance test

N-7130
Table N-X130-1

Maximum operating pressure ×1.25

Currently, it is considered that the PT alone can be applicable.
*1: JSME's Codes for Nuclear Power Generation Facilities - Rules on Design and Construction for Nuclear Power Plants (JSME S NC1 - 2012)*2: JSME's Codes for Nuclear Power Generation Facilities - Rules on Welding for Nuclear Power Plants (JSME S NC1 - 2012)©International Research Institute for Nuclear DecommissioningNo.121

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[Development Schedule]: Planned: Actual

FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

Interim Report▼

FY2022
12

1

2

3

4

5

Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

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No.122

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: Summary➢ Pre-conditions for remote installation of the sleeve were consolidated, and the results ofstudying the concerned delivery method and equipment were compiled. 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
by tests, etc. were consolidated. 3D measurement, layout of the cameras, etc. are being
studied in detail.
➢ The target height at the time of delivering the PCV connection sleeve was set at 4000mm
which is the same as the height while delivering the access tunnel. The remote
installation equipment was reviewed, and it was found out that a height of 4000mm orless can work.
➢ Actions to be taken in response to the issues concerning remote welding of the sleeve,
compiled during the FY2019-20 subsidy projects, were studied, and issues and items
that need to be verified by tests, etc. were compiled. The testing equipment including
the welding torch and the inspection method are being examined in detail.
➢ Remote installation of the sleeve, remote welding as also the element test plan werestudied and preparations for the test equipment and facility are underway. In the future,
feasibility of procedures and equipment for remote installation and welding of the sleeve
will be verified by element tests.

©International Research Institute for Nuclear DecommissioningNo.123
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]
Solicitation items are listed.
③ 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 area aroundthe structures being installed will be used as the work environment, it is necessary to reduce theradiation dose. Thus, the access equipment becomes a large and heavy object with shielding
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 the structure of the shield of theaccess equipment, and the transportation / installation methods need be studied, and development
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 preconditions required for assessing the shielding functionality
including the state of existence, the type of radiation source, etc. such as the fuel debris retrieved
from inside the PCV, etc. are studied and compiled. Next, studies are carried out including exposure
dose evaluation of 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 and evaluated 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 access equipment will be developed.

©International Research Institute for Nuclear DecommissioningNo.124

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]
Temporary⚫ Some of the conditions for studying the shield thickness were revised and a simple study
building area
Reactor buildingof the shield thickness was conducted.
⚫ Conceptual study of the frame structure was conducted.
Large crane[Issues]
Large ancillary facilities, since the mass to be delivered is large interference during the postprocessing(Access tunnel weight (large) → Delivery weight including CW* (large) → Ancillary facilities (large))
Access tunnel⚫ Feasibility of the method for aditional installation of shield by means of complete remote
operation or partial remote operation.
Counter weight
Approx. 700t
⚫ Structure with minimal defects and assurance of shielding performance (method of verification Multi-axial heavy(Fukushima Daiichi
cart
at completion)
NPS-1)
Total delivery weight at present:⚫ The structure of the access tunnel shield, the transportation and installation method need to be
Approx. 1100 ton (Fukushima
streamlined.
Daiichi NPS-1)*CW: Counter weight⚫ Reduction in weight while maintaining rigidity of the delivery frame
Current
study conditions (Example: Unit 1)
現在の検討条件(例：1号機)
Outer wall of the
増設建屋外壁additionalbuilding

Outer
wall of R/B
R/B外壁

R/B外
Outside
R/B

R/B内
Inside R/B

0.5mSv/h以下
0.5mSv/hor less

アクセストンネル（AT）
Access tunnel (AT)
Weight of the main body of
AT本体重量約425ton
access tunnel approx. 425 ton
BSW

AT loadapprox.
AT荷重
235約235tonton (approx.
45ton/m2)（約45ton/m2）

PCV

AT loadapprox.
AT荷重
215 約215ton
ton (approx.
90 ton/m2)（約90ton/m2）

Debris
UC搬送デブリtransported
100kg
in UC
100kg

150Sv/hR/B load limit
R/B荷重制限
approx.
750 ton/m2
約750ton/m2

Loadcapacity of the entire floor of R/B
R/B1階全体床耐荷重
firstfloor approx. 1.22 to 4.88 ton/m2
約1.22～4.88ton/m2

300[Implementation details]⚫ The preconditions required for assessing the shielding
functionality including the state of existence, the type, etc. of
the radiation source such as the inside of the PCV, theretrieved fuel debris, etc. are studied and compiled.
⚫ The transportation and installation method are studied
including exposure dose evaluation of the procedures andadditional installation of the shielding structure, etc. basedon the strength of the R/B structure and the on-site
workability.
⚫ A simulated test facility of the access tunnel on which theshield will be installed, is manufactured, the elemental planis created, and feasibility such as manufacturing capability,
etc. is verified.

BSW load limit
BSW荷重制限
approx.
750 ton/m2
約750ton/m2[Expected outcome]⚫ Presentation of a reasonable method for
installing the access tunnel shield©International Research Institute for Nuclear DecommissioningNo.125

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Study procedures (policy)]
Consolidation of preconditions
The dose of fuel debris and the dose frominside the PCV, etc. are compiled, and thepreconditions required for calculating shielding
are consolidated.

Consolidation of the delivery methods and loadoutside R/B⚫ Consolidation of the delivery methods (rotation / straightline)⚫ Consolidation of the load outside the R/B⚫ Consolidation of required measures (Are only floor steel
plates sufficient? Does it require piling? etc.)

Setting the target(Setting of target delivery weight)

Shielding assessment(Study of shielding thickness)

The shielding thickness is studied based on
the selected conditions.

Study of the delivery frame

Required shieldradiation〇〇mm

The additional shield installation delivery frame with the
purpose of higher rigidity and reduction in weight is studied,and its structural viability is verified.
Required thickness
during delivery(strength)△ △ mmStudy of additional shielding installation equipment / element tests
Conceptual study of the additional shielding installation method
and installation equipment is conducted. Element tests are
implemented to check the viability of the method.
Additional shielding
thickness
××mm

Review of delivery equipment

Additional shielding
thickness
××mm
Access tunnel
additional shielding
thickness after installation=

Required shieldradiation〇〇mm
Access tunnel
shielding thickness after
completing installation-

Required thickness
during delivery(strength)△ △ mmAccess tunnel
Shielding thickness
during delivery

Small access tunnel delivery weight ⇒ Downsizing the ancillary facilities such as temporary building, etc. ⇒ Shortening of schedule and reduction in cost
©International Research Institute for Nuclear DecommissioningNo.126

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield

Consolidation of preconditions

t=300mmScope of the report

t=300mm

t=300mm[Shielding assessment procedure]

t=110mm(Current state) Cross-section ofaccess tunnel

Assessment of shielding with thecurrent design

Shielding assessment if the wall/ceiling 300mm, floor
110mm

Study of proposal for trimming
down the shielding

Whether or not the wall/ceiling/floor can be trimmed
down uniformly, whether or not neutron shielding isrequired, are studied.

Shielding assessment

Shielding assessment considering the proposal for
trimming down
©International Research Institute for Nuclear DecommissioningNo.127

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Consolidation of preconditions]
The preconditions for calculating the shielding thickness are organized. The radiation source inside the PCV is studied considering its
state of existence (fuel debris, activation, solids, liquids, etc.). The source strength for assessment is calculated by back calculating basedon the actual measured value*.
Further, as the work to be performed inside the R/B is unknown, this study is conducted assuming workers will enter inside the R/B.
Items

Conditions

Target plants

Unit 1, 2, 3 of Fukushima Daiichi
NPS

While transporting fuel debris
inside the access tunnel

No (People are cleared out)

Remarks
In some cases, there are restrictions on the unit
However, shielding thickness is assessed even if this is“Yes”.

Entry inside R/B
During regular times (other thanthose mentioned above)

Yes

Inside PCV

Calculation of source strength forassessment

Back calculated based on actual measured value*(10Sv/h or less inside PCV)

Inside AT

Fuel debris inside the φ200 unit can・Shielding is studied as required
・Quantity of fuel debris transported / dose is assessed
as well.

Concrete2.15 (g/cm3)

Filling factor, etc. is considered.

Iron

7.8 (g/cm3)

Filling factor, etc. is considered.

Inside R/B

1 mSv/h (During regular times)

Outside R/B

0.05 mSv/h

Radiation source

Material density

Target dose rate after
installation of access tunnel(additional part)(Note)
・ The target dose rate is tentatively considered to be 1mSv/h. It is planned 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 is verified by means of the actual measured value. The neutrons at the time of passing through the access tunnel are evaluated.

The shielding thickness and additional shielding thickness of the access tunnel is determined based on the above conditions, and the additional installation method and installation equipment are studied.

* Results of the on-site demonstration test during the investigation on the first floor grating outside the pedestal (B1 investigation) stated under “Development of Technology for Investigation
Inside PCV” on the TEPCO website (4/30/2015): 10Sv/h or less inside the PCV.
©International Research Institute for Nuclear DecommissioningNo.128

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Consolidation of preconditions]Shielding assessment was carried out under the following conditions.
Items

Unit

Unit 1, Fukushima
Daiichi NPS

Unit 2, Fukushima
Daiichi NPS

Unit 3, Fukushima
Daiichi NPS

Shieldingassessment
conditions

Initial concentration

wt%

3.7

Same as on the left

Same as on the left

3.7

Burn-up

GWd/tHM

40.17240.55740.49941

Specific output

MW/tHM

20.0

25.3

Same as on the left

20.0*

Cooling period

Year

20

Same as on the left

Same as on the left

9

Fuel debris composition(Weight)―

UO2(Weight calculated
assuming UO2=1t)

Same as on the left

Same as on the left

UO2
(Weight calculated
assuming UO2=1t)*Studied based on Unit 1, as there is almost no impact.

The following is used for calculating burn-up.
⚫ Calculation code： ORIGEN2.2 UPJ⚫ Cross-sectional area library: BS340J33⚫ DECAY library: JNDECAY33.LIB⚫ Photon library: gxuo2brm.lib©International Research Institute for Nuclear DecommissioningNo.129

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Consolidation of preconditions]
The study conditions and dose rate evaluation points are indicated below.

(Vacuum)(Vacuum)(Vacuum)

Fuel debris

Fuel debris

Fuel debris
Access tunnel (Iron,

Evaluation location： Distance from theside of the access tunnel
Evaluation height: Height from the floor
surface of R/B first floor

Imaginary shielding plate (Prevention of leakage radiation dose)
Floor (Concrete,
Evaluation point©International Research Institute for Nuclear DecommissioningNo.130

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Evaluation result] Shielding thickness: Wall/Ceiling 300mm, Floor 110mm (Quantity of fuel debris 30kg×2)[30kg/can x 2 cans, evaluation height 120cm, keff=0.95]

Neutron beams

Neutron beams

Secondary gamma rays

Secondary gamma rays

Gamma rays

Gamma rays

Gamma rays inside PCVDose rate (mSv/h)

Dose rate (mSv/h)[30kg/can x 2 cans, evaluation height 10cm, keff=0.95]

SurfaceGamma rays inside PCV

Surface
Evaluation location

Evaluation location[30kg/can x 2 cans, evaluation height 120cm]

Dose rate (mSv/h)

Dose rate (mSv/h)[30kg/can x 2 cans, evaluation height 10cm]

・ Source strength forassessment is calculated forthe radiation source frominside the PCV.The dose rate
calculated based on theaccess tunnel shielding
thickness is added.
・10μSv/h is added to theevaluation on this page.

Surface

Surface
Evaluation location

Evaluation location

As the dose of neutron beams is high, neutron shielding needs to be installed for trimming down the shielding thickness. In the vicinity of the floor surface, the dose rate fromgamma rays is high due to reflection.
©International Research Institute for Nuclear DecommissioningNo.131

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Evaluation result] (Reference evaluation) Shielding thickness： Wall/Ceiling 250mm, Floor 110mm

Wall/Ceiling 250mm, Floor 110mm is estimated based on the calculation results Wall/Ceiling 300mm, Floor 110mm.
As a result of rough calculations, it is assumed that the target dose rate is sufficiently satisfied even when the
Wall/Ceiling thickness is 250mm.
(Note) For the evaluation carried out at the evaluation height of 10cm (floor surface) rough calculations are
not performed since there is the effect of reflection.
[30kg/can x 2 cans, evaluation height 120cm][30kg/can x 2 cans, evaluation height 120cm, keff=0.95]

Neutron beams

Dose rate (mSv/h)Gamma rays
Gamma rays inside PCVDose rate (mSv/h)Secondary gamma rays

Surface

Surface
Evaluation location

1mSv/h or less is satisfied even when the shielding thickness is 250mm.

Evaluation location
・ Source strength for assessment is calculated forthe radiation source from inside the PCV.The dose
rate calculated based on the access tunnel
shielding thickness is added.
・28μSv/h is added to the evaluation on this page.

It is assumed that 1mSv/h is satisfied even when neutron shielding is installed resulting in
Wall/Ceiling 200mm and Floor 120mm.
©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.132[Loading conditions of the delivery equipment] Structure of the X-Y jack
In order to study whether or not ground improvement is necessary, the ground pressure of the access tunneldelivery equipment (delivery jack) is studied.
Specifications
Vertical jack

Delivery jackCapability

Capability (Push Pull)

StrokeStrokePressure receiving area

PressureRequired amount of oil approx.

Pressure receiving
area (Push)(Pull)
Pressure (Push)(Pull)
Required amount ofoil approx.

Horizontal adjustment jackCapability
StrokePressure receiving
area (Push)(Pull)
Pressure receiving area
(Push)(Pull)
Required amount ofoil approx.

Horizontal adjustment jack

Pull side pressure oil
inlet
Adjustable installation
K-5 type
Push side pressure oil
inlet
Adjustable installation
K-5 type

Vertical jackVertical pressure Vertical pressure
oil inlet (Return)gauge (Push)

Conditions of the jack⚫
Maximum ground pressure: P= 2,608.9[kN/m 2]⚫
Impact coefficient: i = 0.20⚫
Breadth of the jack: B = 0.950 [m]⚫
Length of the jack: L = 2.200 [m]Conditions of the floor steel plates⚫
Thickness of the floor steel plates: t = 0.030 [m]⚫
Breadth of the floor steel plates: PB = 1.500 [m]⚫
Length of the floor steel plates: PL = 6.000 [m]⚫
Active loading width of the floor steel plates: B’ = 1.500 [m]⚫
Active loading length of the floor steel plates: L’ =2.100 [m]⚫
Modulus of deformation of the floor steel plates: E=2.000E+08 [kN/m2]

Vertical pressure
oil inlet (Push)

Horizontal jackVertical stop valve(Push)
Vertical stop valve(Push)

Horizontal adjustment
support point

StrokeGround pressure of the lower surface of the floor steel plates: Pmax’ = 2,077.2 [kN/m2]©International Research Institute for Nuclear DecommissioningNo.133

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Loading conditions of the delivery equipment] Soil boring log

The load bearing capacity of the area in the vicinity of the Fukushima Daiichi NPS is calculated for the study to determine whether or
not ground improvement needs to be conducted for reference.
Soil boring log (Standard penetration test)(Note) Subsurface exploration of the area where
equipment will be installed needs to be conductedwhen actual equipment is studied.

Ground conditions
Layer thickness

GeologicalstrataUnit weight

Frictional
angle Φ(degrees)

Adhesive force

Poisson’s ratio

First stratum
Second stratum
Third stratum
Fourth stratum

Modulus of deformation of the ground
GeologicalstrataModulus ofdeformation

N valueFirst stratum
Second stratum
Third stratum
Fourth stratum

Allowable bearing capacity qa = 29 (kN/m2)
Ground pressure of the lower surface of the floor steel
plates: Pmax’ > allowable bearing capacity

Ground improvement is required.
©International Research Institute for Nuclear DecommissioningNo.134
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Conceptual study of additionally installed structures]
The shield that will be post installed needs to be selected considering the shielding performance of the access tunnel
and installability. The prospective shielding material and results of comparative studies are provided.

Proposal

Shieldingmaterial

Shielding effect*

Ability to remotely
install the shielding
material

Evaluation of theshielding performanceafter installation

Issues1

Steel (plate)

Major

Acceptable

Good

Method of remote installation(Difficulty level - high)2

Steel (balls)

MediumGood

Acceptable

Method of remote installation,
Filling factor (shielding
performance)

3

Lead (balls)

Major

Good

Acceptable

Method of remote installation,
Filling factor (shielding
performance)

4

Lead (casting)

Maximum

Unacceptable(High temperature,
deformation)

Acceptable

Method of remote installation,
Deformation after casting, specificgravity5

MortarLow

Good

Acceptable

Method of remote installation,
Filling factor (shielding
performance)

Remarks: *Comparative evaluation between the materials

The ability to shield is inadequate depending on the filling factor. Hence in the case of proposals 2, 3, 4 and 5 that areevaluated based on the filling factor, the external dimensions of the access tunnel are likely to increase.
In the future, comparative evaluation will be conducted while referring to the schematic diagram for selecting the proposal
for additional installation of structures.
©International Research Institute for Nuclear DecommissioningNo.135

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Conceptual study of additionally installed structures] Schematic diagram of the push method for the plate-shaped shield(Comparative evaluation with other proposals is planned to be conducted in the future)

Outline⚫ Pushing the plate-shaped shield from outside
the R/B is proposed.
⚫ Guide roller is installed on the shield anddelivered.
⚫ Method of installing the shield at the curved
section is a challenge.
⚫ In the current state, it is rated to be highly
viable.
Shielding thickness
While delivering: Wall/ceiling: 100mm, Floor: 110mm
Additionally installed shielding: Wall/ceiling: 200mm,
Floor: 0mm
Upon completion: Wall/ceiling: 300mm, Floor:
110mm
Additionally installed shield©International Research Institute for Nuclear DecommissioningNo.136

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Conceptual study of additionally installed structures] Schematic diagram of the partitioning method for theplate-shaped shield (Comparative evaluation with other proposals is planned to be conducted in the future)

Outline⚫
Installing the additional shield on the floor surface on
first floor of R/B is proposed. It is evaluated that witha thickness of about 85mm load gets distributed andthus the 4.9ton/m2 load capacity of the R/B floor ismet.
⚫
Method of carrying-in/out and installation of theadditional shielding plate is a challenge.
⚫
Viability needs to be evaluated.

Shielding thickness
While delivering: Wall/ceiling: 215mm, Floor: 110mm
Additionally installed shielding: Wall/ceiling: 85mm, Floor:
0mm
Upon completion: Wall/ceiling: 300mm, Floor: 110mm

Additionally installed shield©International Research Institute for Nuclear DecommissioningNo.137

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield[Conceptual study of additionally installed structures] Schematic diagramof the shielding material filling method (Steel balls/casting)

Additionally installed shield
Outline⚫
Filling shielding material after the access tunnelframe is connected to the PCV connection sleeve is
proposed.
⚫
Steel balls or casting are considered for the fillingmaterial.
⚫
Evaluation of shielding performance is a challenge.
⚫
Feasibility is rated low,
(Note) The figure illustrates 1 unit.

Shielding thickness
While delivering: Wall/ceiling: 100mm (assumed), Floor:
110mm
Additionally installed shielding: Wall/ceiling: 200mm, Floor:
0mm
Upon completion: Wall/ceiling: 300mm, Floor: 110mm©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.138[Course of studies in the future]<Dose evaluation>⚫ Since neutron beams contribute a lot, neutron shielding will be studied. As it is difficult to install the neutron shielding on the main bodyof the access tunnel, overpacking the unit can will be considered.
⚫ Shielding thickness will be evaluated once again considering Wall/ceiling: approx. 200mm, and Floor: 110mm as the target shielding
thickness.
<Ground maintenance>⚫ The method and schedule for ground maintenance will be organized.
⚫ The equipment required for delivery will be organized.
<Additional installation of shielding structures>⚫ Comparative study of the proposals will be conducted, and the appropriate proposal will be selected.
⚫ The structure of the selected proposal will be studied, and element tests will be planned.

<Vision for the study> The shielding thickness will be reduced based on the shielding assessment, and access tunnel
will be installed using the method for additional shield installation.
Unit 1

Current state

Proposal 1 (Slide No. 135)

Proposal 2 (Slide No. 136)

Delivery of unit in
its entirety

Plate-shaped shield push method

Plate-shaped shield partitioning method

MethodUpon completion of
installation

Upon completionof installation

At the time ofdelivery

Additional
installation

Upon completionof installation

At the time ofdelivery

Additional
installation

Wall/ceiling (shielding
capability)

300mm

200mm

50mm

150mm

200mm

115mm

85mm

Floor (shielding capability)

110mm

110mm

110mm

0mm

110mm

110mm

0mm

Weight

425 ton

325 ton170 ton155 ton235 ton235 ton

100 ton(Note) The method of filling shielding material is not mentioned as its viability is low.
©International Research Institute for Nuclear DecommissioningNo.139
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield: Planned: Actual[Development Schedule]
FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

Interim Report▼

FY2022
12

1

2

3

4

5

Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

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No.140

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]③ Installation of shield: Summary➢ The course of study and the preconditions were organized for studying the method for
additional shield installation. As a result of shielding assessment it was found thatneutron shielding needs to be installed for reducing the shielding thickness, as the doseof neutron beams is high.
➢ Considering the shielding performance and installability of the shielding material thatwill be installed later, steel plate delivery, filling of steel balls and casting, mortar filling
method have been studied and their comparative evaluation is underway. In the future,comparative evaluation will be conducted while referring to the schematic diagram forselecting the proposal for additional installation of structures.
➢ In the future, the feasibility of the method for additional shield installation will be verified
by tests.

©International Research Institute for Nuclear DecommissioningNo.141
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]
Solicitation items are listed.
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, blockout) in front of 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 efficient disassembly in confined spaces needs to be studied and developed.
Studies will be conducted on the method of cutting, disassembling and removing the shield plug,etc. safely and with certainty in the confined space inside the R/B, transferring the disassembled
structures and storing them in waste containers by remote operation, considering that this work is
carried out in a high dose environment; and on the procedures considering prevention of dust
dispersion, removal of structures required for strength such as intermediate posts, smoothening thecut 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.142

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 weredeveloped, conceptual study and evaluation of the roughly estimatedexposure dose were carried out.
[Issues]< Common to Units 1 to 3>⚫ As the shield plug is large and heavy and hence difficult to remove,
removal technology needs to be developed.
⚫ Feasibility of the disassembly equipment, etc. considering the load on thefloor surface of the building.
⚫ Method of disassembling considering prevention of dust dispersion undera high dose environment.
⚫ Increase in exposure dose due to increase in the amount of work carriedout on-site for finely cutting large and heavy objects.
<Unit 1>
⚫ Method of pulling out the shield plug considering anchoring, etc. of thedrive 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 block)

Steel plate + Concrete

Reinforcement + Concrete

Illustration of the method of disassembling
Similar examples from overseas (WAK)
Fukushima
Daiichi
NPS Unit 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.143

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 storing them into
waste containers by remote operation. Studying the method
for preventing dust dispersion, method for disassembling andtransferring 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 andimplementing 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

Comprehensive view of
the Unit 1 shield plug

<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 (Removalusing a cantilever)After removing the concrete
block (Fukushima Daiichi
NPS-4 X-1B)
Actuator
Made of steel
CounterweightFrame

Cuttingequipment(horizontal)<Units 2, 3>⚫ Study of remotely operated block-out equipment⚫ Study of method for smoothening the floor surface
Cuttingequipment(vertical)[Expected outcome]⚫ Presentation of the method of removing the shield plug, etc.

Method of finecutting

Method of transferring
unitized structures

Illustration of Unit 1 shield plug removal©International Research Institute for Nuclear DecommissioningNo.144

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 plan

Consolidation 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 development of development plan

©International Research Institute for Nuclear DecommissioningNo.145

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Consolidation of preconditions]
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 the southernside. 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 theblock wall.
Proposal for installaing 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
M
桝
集

１/2号機サービス建屋AsE

New structures
M
Co

M

集
P

集

C

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
R
w/B
Access tunnel

M
扉止P
FSTR建屋(1,2機)

TEL

H.H

M
集

消火設備小屋Exhauststack

LP-G屋外中継盤

M

M

FH

雨集

油分離層

扉止
集

Co

沈殿層

M
M

桝
扉止
集

M

集

扉止

TEL

照

集

桝
M

桝
桝
集

H.H
警備詰め所

Exhaust
stack

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(Sample image)©International Research Institute for Nuclear DecommissioningNo.146

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Implementation details (Overview)]⚫ The preconditions for Units 1 to 3 and the disassembly methods are studied.
⚫ The disassembly of shield plug is studied for Unit 1 and that of the concrete blocks is studied for Units 2 and 3.
⚫ In addition to the method of disassembling the shield plug inside the R/B in Unit 1, the method of transferring unitized
structures is briefly studied as well.
⚫ Either of the disassembly methods are general disassembly methods for Unit 1 and Units 2, 3, however, as the concrete
blocks have an impact* on the installation accuracy of the PCV connection sleeve, element tests on disassembling theconcrete blocks are conducted during this project.
* As the PCV connection sleeve is installed on the floor surface after disassembling the concrete blocks, it⚫ This report focuses on Unit 3.
easily gets affected by uneven floor surface. In the case of the shield plug, even though there is the rail, thesurface is assumed to be comparatively smooth.

Units 2, 3 Concrete blocks

Unit 1 shield plug
Outer plate

2805

Mortar(Filling the gaps)

Liner plate
Intermediate support for thewall (Intermediate posts)

2885

3490
2390

3510

1600

Actuator©International Research Institute for Nuclear DecommissioningNo.147

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

Unit 1 shield plug

Units 2, 3 Concrete blocks

Overview of the target

Mainly entire blocks of concrete that normally travel over therail on electricity.

Blocks are stacked like bricks and some of the gaps are filledwith mortar.

⚫

①

Main procedures(Prior to the accident)⚫

⚫

(Measure 1) Pulling out by moving with the help ofelectricity.
(Measure 2) Pulling out by rotating the shaft (external
drive shaft) connected to a motor, etc. The external drive
shaft was powered, had 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 be used. If it can be used, the shield plug should be pulled
out using the external drive shaft. If it cannot be used, it shouldbe pulled out using a winch.
Removal policy in thisPJ・Before pulling, it should be made sure that there is no foreignmaterial (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. (Themortar between the BSW and the block was 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.
・Prior to the accident, since the blocks (approx. 800 blocks)
were re-used, they were removed carefully to ensure there isno damage, but this time they do not need to be restored.
・Cutting with the help of wire saw was considered, but it wasdetermined that using a wire saw would be difficult because of
the depth.

©International Research Institute for Nuclear DecommissioningNo.148

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Consolidation of preconditions (Unit 3)]➢ Objects to be removed (Concrete blocks) *1➢ Environmental Conditions *1

Concrete blocks (Enlarged view)
Mortar(Filling the gaps)

Items
TargetDimensions
Mass

Liner plate (Outside the scope of removal *2)
Intermediate support for the wall
(Intermediate posts)
Partitioning
steel plate

Composition
Air dose rate
Floor load bearing
capacity

2885

Reinforcement

Specifications
Units 3Concrete blocks
W 3510×D 1600×H 2885(mm)Approx. 36 ton
Concrete wall + band plate + wire torus＋ intermediate support for the wall, mortar finishingof gaps
Approx. 18 mSv/hApprox. 4.9 ton/m2

Carrying-in/out

Western side of R/B (Truck bay door
(W4900×H4900mm))

Height at which workis carried out

Approx. 4m or lessAir dose rate on the southwestern side (work area)of the R/B first floor in Unit 3

3510

1600

Foundation bolts

Band plate,wire torus
BSW

Concrete blocks

T
r
u
c
k
b
a
y
d
0.12
o
o
r

Numbers indicate air doserate(mSv/h)Concrete blocks

0.70: Data collection period: April 1, 2020 to March 31, 2021

*1: The structures and dimensions include those from drawings from other units that wereused as reference and hence include estimates as well.
*2: As it gets embedded into BSW: Measured on November 24, 2021

©International Research Institute for Nuclear DecommissioningNo.149

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Requirements (Unit 3)]➢ Safety requirements
Safetyrequirements

Work requirements / functional
requirements

Worker exposure reduction
Prevention ofexcessive andinternal exposure ofworkers

Prevention of dust dispersion during thework of disassembling concrete blocks

Prevention ofexcessive exposure
to radiation

Shielding of radiation from the BSW
opening

Response policy
The air dose rate should be reduced bydecontaminating the work area to the extent
possible.
The exposure due to work carried out byhumans should be reduced bydisassembling the concrete blocks remotely(crane).
Exposure should be evaluated by studying
disassembling procedures and the required
number of workers should be established.
A work room should be set up to contain
dust dispersion.
Dispersion should be contained by sucking
in dust using a ventilation system.
After disassembling, a remotely operated
temporary shield should be installed.

©International Research Institute for Nuclear DecommissioningNo.150
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Study of disassembling method (Unit 3)] Selection of a craneExample of 3 to 4 ton class

Example of 6 to 8 ton class
Hitachi Construction
Machinery Co. Ltd.
ZAXS75US-5B
Short reachspecifications
K cab

Hitachi Construction
Machinery Co. Ltd.
ZAXS35U-5B
Short reach specifications

Photograph*

Dimensions

Specifications

To beprocessed

W 1650×D 4050×H 2540(mm)W 2320×D 4820×H 2820(mm)Mass of machinery: 3840kg

Mass of machinery: 7430kg

Mountable attachment mass: 450kg

Mountable attachment mass: 1430kg

Maximum height at which work is carried out：
4240mmMaximum height at which work is carried out： 5590mm

Average ground contact weight: 3.0ton/m2

Average ground contact weight: 3.8ton/m2

Disassembling and removing concrete blocks,
band plate, wire torus, mortar

Disassembling and removing the intermediate support for thewall*： External dimensions when the crane is set down are assumed.
©International Research Institute for Nuclear DecommissioningNo.151

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Study of disassembling method (Unit 3)] Selection of processing and finishing tools
No.

Tools

Sample image

Generally used for

To be processed

Outline specifications [Crane used]1

Breaker(Product with a model
number)For crushing concrete

Concrete blocks,
BSW (Floor)[3 to 4 ton class]
To be processed: Concrete, bedrock,hard floor, road work

2

Grabbing equipment(Product with a model
number)For grabbing andcollecting pieces ofconcrete3

Bucket(Product with a model
number)For collecting pieces,[3 to 4 ton class]Concrete block debris
etc. of concrete
Capacity (m3): 0.11

Concrete blockdebris, band plate,[3 to 4 ton class]wire torus,
Weight that can be held (kg)*: 280
intermediate support
for the wall*: Calculated by subtracting the tool mass from the mountable attachment mass of the crane©International Research Institute for Nuclear DecommissioningNo.152

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Study of disassembling method (Unit 3)] Selection of processing and finishing tools
No.

Use

To be processed

Outline specifications [Crane used]

4

Cutting equipment(Guzzilla cutter)(Product with a model
number)For cutting, grabbing
and collecting wire
torus, reinforcement,
partitioning steel plates

Wire torus,
reinforcement(L100×100×7),
partitioning steel plate(PL6)

Target: Iron frame, reinforced concrete[3 to 4 ton class*2]
Major cutting of H type beam: Refer to A
in the table below[6 to 8 ton class]
Major cutting of H type beam: Refer to B
in the table below

5

Circular saw
Cutting equipment

For cutting partitioning
steel plates, foundationbolts (ceiling)

Partitioning steel plate [6 to 8 ton class](PL6)
Cutting depth (cm): 27
Foundation bolts (φ19) (Reinforced concrete)

Smoothening tools

For smoothening BSW(floor)(Smoothening after
removing reinforcement(floor), and foundationbolts *1)

6

Tools

Sample image*1: Floor smoothening for installation of PCV connection sleeve*2: Assuming wire torus (4.5mm copper wire) is cut.

It is assumed that regular floor hardpacking tools will be attached to thecrane.

Poured mortar

H type beam (broad)(mm)

H type beam (narrow/medium
width)(mm)

H

B

t1

t2

H

B

t1

t2

A

125

125

6.5

9

200

100

5.5

8

B

200

200

8

12

350

175

7

11

H type beamdimensional drawing©International Research Institute for Nuclear DecommissioningNo.153

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Study of disassembling method (Unit 3)] Study of disassembly procedures (1/2)
1. Work of carrying-in the equipment
Ventilation
system

2. Disassembly of concrete blocks from the front side

Concrete blocks

Work room

3. Collection of concrete blocks
Ventilation
systemConcrete blocks

Concrete blocks

Work room

Breaker

Door

Door
Crane

Crane

Truck bay door
Remotely operated
temporary shieldTemporary building
Image

Truck bay door
Receptacle fordisassembled pieces

Temporary building
Image

Front (depth approx. 800mm)

Transportation
cart

Remotely operated
temporary shield

Additional information: Interfering objects removed,
temporary building set up completed

Additional information: Wire torus cut with the cutting
equipment

Additional information: If collecting with the bucket is not possible,
collection is done using the grabbing equipment

4. Installation of preventing member

5. Disassembly of concrete blocks from the back side

6. Removal of reinforcement (front, middle, back)Ventilation system

Concrete blocks
Preventing
memberWork room

Concrete blocks
Back (depth approx. 800mm)

Ventilation system
Work room: Site to be cut
Cutting equipment

Intermediate support
for the wall
Reinforcement (front)

Preventing
memberPreventing
member

Door

Door
Crane
Truck bay door

Temporary building
Image

Transportation
cart
Remotely operated temporary
shieldAdditional information: Being planned for preventing debris from falling inside theequipment hatch

Truck bay door

Transportation
cart

Crane
Preventing

Receptacle for
Reinforcement
Reinforcement
Reinforcement member(Front)(Middle)(Back)
disassembled pieces
Remotely
operated
temporaryTemporary building
Additional information: Disassembled and removed in the order ofshieldImage
Reinforcement (front) ⇒ Partitioning steel plates ⇒ Reinforcement
Additional information: Implemented in the same manner as(middle) ⇒ Partitioning steel plates ⇒ Reinforcement (back)No. 2 and 3

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.154
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Study of disassembling method (Unit 3)] Study of disassembly procedures (2/2)
7. Removal of partitioning steel platesIntermediate support

8. Removal of foundation bolts (ceiling): Site to be cut

for the wall
Circular saw
steel
Cutting equipment Partitioning
plate

Preventing
memberCircular saw
Cutting equipment Foundation bolt

Foundation bolts (ceiling)

Partitioning steel
plate

Additional information: Disassembled and removed in the order of Reinforcement(front) ⇒ Partitioning steel plates ⇒ Reinforcement (middle) ⇒ Partitioning steel
plates ⇒ Reinforcement (back)Foundation bolts (floor)
Additional information:Foundation bolts (floor) and reinforcement (floor) can beremoved after the floor surface is shaved

Smoothening tools

12. Clearing

Filling with mortar, etc.

Preventing
memberMortar pouring
equipment

Traces of disassemblyof BSW (floor)

Preventing
member

11. Smoothening

Filling with mortar, etc.

Cart

Additional information: BSW (floor) is disassembled up to the same depth as No. 9and then mortar is poured.

Ventilation
systemPreventing
memberPreventing
memberMortarPreventing
memberIllustration of [Illegible]
for removing
foundation bolts

BreakerPreventing
memberAdditional information: Reinforcement (ceiling) can be removed along with theremoval of foundation bolts (ceiling)

10. Pouring of mortar

Mortar pouring
equipment

Foundation bolt

Preventing
memberPreventing
memberReceptacle fordisassembled
pieces

9. Removal of foundation bolts (floor)

Door

Traces of disassemblyof BSW (floor)

Truck bay door

MortarRemotely operated
temporary shieldTemporary building image
Additional information: Mortar poured in No. 10 is leveled and smoothened

Additional information: Removing the equipment and moving the remotely
operated temporary shield・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.155
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug
[Exposure assessment (Unit 3)]
Disassembly
procedures
No.

Assumed human work

Work place

Total time required
for work

Environmental
radiation dose

Exposure dose(hr)(mSv/h)(mSv/person)

21

11 to 18350

4 to 51462

Number of persons

Exposure dose

(mSv)

1

Carrying-in and assembling the ventilation equipment and workroom, carrying-in the remotely operated temporary shield2

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

Inside R/B

Temporary building

Total1477.12Since the dose rate inside the R/B is high, the exposure dose during the disassembling procedure 1 is high, and as a result 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No.156

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Identification of issues (Unit 3)]
Issues / items that need to be studied
Disassemblingprocedures

Item
Work environment

Work ofcarrying-in theequipment

Suction performance conditions of
the ventilation equipment

Human work /Remoteoperation

Details
Decontamination is required as the work is carried out under high dose environment.
Ventilation equipment that can collect the dust resulting from disassembling of concrete blocks is required.

Human work-

Structure of cart for moving the air
inlet

Structure that enables moving (including handling of the hose) by remote operation needs to be considered.

Transfer conditions

The conditions for transferring from inside the R/B need to be set and work needs to be carried out inaccordance with the transfer standards.

Remoteoperation
Remoteoperation
RemoteoperationWork room structure

The structure of the work room (air-tightness, reducing the installation time) needs to be studied.

Human work

Work environment

The method of monitoring the environment (dose, dust, etc.) depending on the progress of work needs to bestudied.

Human work

As the air dose rate at the work site is approx. 18mSv/h, crane specifications that enable disassembly by remote
operation need to be studied (including wired and wireless / utility supply).

Remoteoperation

Collection method when there is a failure, and measures to be taken if the crane becomes an object with highdose rate, (installation of dust cover) are required.

Remoteoperation

Feasibility of work with the equipment meeting the following conditions based on the work environment⚫ Selection of crane depending on the work space⚫ Floor load bearing capacity 4.9 ton/m 2⚫ Carrying-in/out from the truck bay door (W4900×H4900mm)⚫ Height at which work is carried out: approx. 4m or lessRemoteoperation

As the air dose rate at the work site is approx. 18mSv/h, a transportation cart for collecting the remotely
disassembled concrete blocks needs to be considered.

Remoteoperation

Disassembly
and removal of Crane specifications
concreteblocksTransportation cart specifications

A structure that enables filter replacement by remote operation needs to be considered.

©International Research Institute for Nuclear DecommissioningNo.157
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Identification of issues (Unit 3)]
Issues / items that need to be studied
Details

Humanwork /
Remoteoperation

Processing and finishingtools(Processing work)⚫ Processing and finishing tools (processing) need to be studied considering the working
position and work space (Basically a product with a model number is used).
⚫ Measures against dust generated during processing (Prevention of it adhering to thecrane and processing tools / decontamination efficiency, etc.)⚫ Exposure reduction during tool replacement

Remoteoperation

Processing and finishing
tools(Collection work)⚫ Processing and finishing tools (collection) need to be studied considering the working
position and work space (Basically a product with a model number is used).
⚫ Collection of disassembled pieces that have scattered (particularly disassembled pieces
that are small / in powdered form)

Remoteoperation

Installation ofPreventing member
preventing
specifications
memberBeing studied along with the need for measures to prevent debris from falling inside theequipment hatch

Remoteoperation

Smoothening Smoothening conditions

Smoothening conditions required for installing the PCV connection sleeve need to be set
and the feasibility of smoothening work by remote operation needs to be verified.

Remoteoperation

Disassemblingprocedures

Items

Disassembly
and removalof concrete
blocks©International Research Institute for Nuclear DecommissioningNo.158

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Element test plan]No.

1

To be processed

Concrete blocks

Direction ofprocessing

In alldirections

Processing andfinishing tools

To betestedVerification contents

Criteria (Measurement and confirmation items)〇① Verifying whether or not it is possible to smoothen
the mortar stuck on the lining plate

The mortar should not be significantly stuck on to thewall surface. (Height at which it is stuck, and area overwhich it is stuck)〇② Verifying the impact when the breaker collides withthe partitioning steel plates or reinforcement

There should not be any significant deformation.
(Condition of damage/deformation)

Breaker2

Reinforcement (front, middle,
back)(L100x100x7)

Horizontal

Cutting equipment-

Cutting is believed to be possible.

－

3

Reinforcement (ceiling)(L100x100x7)

Horizontal

Circular saw
cutting equipment-

Cutting is believed to be possible.

－

4

Reinforcement (floor)(L100x100x7)

Downwards

Breaker〇

Confirming the status after shaving* It is believed thatshaving is possible, but it is performed considering
subsequent processes.

Cutting equipment-

Cutting is believed to be possible.

－

Partitioning steel plate (PL6)

Horizontal
Upwards
Downwards

Circular saw
cutting equipment-

Cutting is believed to be possible.

－

Upwards

Circular saw
cutting equipment-

Cutting is believed to be possible.

－

Downwards

Breaker〇

Confirming the status after shaving* It is believed thatshaving is possible, but it is performed considering
subsequent processes.

There should not be any remnants (foundation bolts)
and shaving should be possible. (Maximum depth,
maximum width)

Downwards

Smoothening tools〇

Verifying the extent of smoothening possible by meansof a crane.

There should not be any significant unevenness anddips. (Dip, height)

5

6

7

There should not be any remnants (L type beam) andshaving should be possible. (Maximum depth,
maximum width)

Foundation bolts (φ19)

Poured mortar* Considering the installation of the PCV connection sleeve in subsequent processes, the plan is toimplement the test focusing on the lower part (floor).
©International Research Institute for Nuclear DecommissioningNo.159
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Scope of simulation]
Intermediate post

Wall
(High strength mortar)

288
5Foundation bolts

160
0

351
0

Fukushima Daiichi NPS-3
Concrete blocks
Scope of simulation (section
marked with the red line)

Floor(High strength mortar)
Floor slab
(High strength reinforcing concrete /approx. 3000kg

Scope of simulation(section marked withthe red line)©International Research Institute for Nuclear DecommissioningNo.160

6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug

[Development Schedule]: Planned: Actual

FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

Interim Report▼

FY2022
12

1

2

3

4

5

Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

12

1

2

3

Final report▼

1. Conceptual study
2. Element testplanning
3. Test preparation /Testmanufacturing oftest equipment
4. Element tests
5. Summary

Remarks©International Research Institute for Nuclear DecommissioningNo.161
6. Implementation Items of This Project [1) (1) Development of the Method for Installing Access Equipment]④ Disassembly of shield plug: Summary➢ The course of study and preconditions pertaining to the method of transferring the Unit 1
shield plug in its entirety, were consolidated, and the removal procedures were studied
briefly. The disassembling procedures were organized.
➢ The course of study and preconditions pertaining to the method of disassembling theconcrete blocks in Unit 2, 3 were consolidated, and the disassembly and removal
procedures were studied briefly. The disassembling procedures were organized➢ Issues in the procedures for disassembling and removing the shield plug in Unit 1 andthe concrete blocks in Units 2 and 3 were identified, and the roughly estimated radiationdose was assessed. Although either of the disassembly methods are general
disassembly methods, as the concrete blocks have an impact on the installation
accuracy of the PCV connection sleeve, element tests on disassembling the concrete
blocks will be conducted in the future.
➢ In future, processing tools will be evaluated and the feasibility of the methods will beverified by element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This ProjectNo.162

1) Development of the side access method(2) Development of disassembly and removal technology
Solicitation items are listed.
① HVH disassembly
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 pipes, installing
utilities (hose, etc.), etc. which is carried out outside the pedestal inside the PCV using remotecontrolled equipment, was developed so far.
This development will enhance fuel debris retrieval throughput by securing a work area by
removing large HVH from among the equipment installed outside the pedestal, as also will
enhance the work efficiency of removing fuel debris and deposits from the basement floor of
the pedestal. Also, as heavy mortar (several hundred kilos) is placed on top of the HVH,
technology for disassembling while ensuring it does not fall, is required. Upon studying andorganizing the requirements 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 and devices
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 removal technology]① ＨＶＨ disassembly

No.163Development 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
equipment can be carried in
About 700mm opening

Positioning
移動アーム
arm

Fundamental technology upgrade (Implemented in FY2017-18)[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 (The method of setting up
dikes was selected)

Assembly typebeam

Task arm
作業アーム

Further Increasing the Scale of Retrieval (Implemented in FY2019- 20)

Flexible taskarmInterference removal
equipment

CRD
opening

Hose[Study of response measures based on the issues]➢
Method of establishing 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)

Flexibletask arm
Positioningarm

Formwork

Platform beam
Flexible task arm

Positioningarm

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 inside the pedestal (CRDchanger)➢
Method of removing interfering objects from inside the pump pit

Outsourced to TEOCO HD (Implemented in FY2020-21)[Conceptual study of HVH disassembly]➢
Consolidation of preconditions➢
Conceptual study of HVH disassembly
methods➢
Identification of issues

Positioningarm
CRD carry-in
entrance

Platform

CRD supporting
structures

CRD
changer

Items to be studied in the future➢

Study of developmental challenges identified during engineering andtechnical development
Etc.

Middle work
frame

Portion embedded at
the pedestal bottom©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]① HVH disassembly

No.164The correlation between the development of HVH disassembly and removal technology outsourced to TEPCO HD and thisproject is shown below.

1. Conceptual study

Identification of element test items
Detailed study of element test contents

2. Element test planning

Unit test on cutting using existing robots
Designing & manufacturing equipment

3. Test preparation / Test
manufacturing of test
equipment

Basic test on cutting
Unit test on cutting by one arm of the HVH disassembly robot

Unit test on cutting using HVH disassembly robot
4. Element test

Element test
5. Summary: Being started: Completed: Results of outsourced operations

This project will be appropriately implemented based on the results of outsourced operations.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.165① HVH disassembly◼
Equipment limitations and dimensions (1/2)➢ The equipment, etc. will be inserted inside the PCV through the access tunnel connection sleeve equipment hatch.
The dimensional conditions that would enable passage through the route mentioned above are provided below.
Note that, the PLR pump is installed in front of the equipment hatch (315°) in Units 2/3. Hence in order to insert large equipment, the
PLR pump terminal box will be removed.
(The PLR pump and motor will not be removed)➢ It was assumed that HVH disassembly and removal will be possible by means of robots and equipment that fit the maximum
dimensions for being able to pass through.
Hence it was decided that the PLR pump will not need to be removed.
2550
1300
PLR pump terminal box

1000

PLR motor
By removing the PLR pump terminal box
equipment of length up to 2,400mm can be rotated.

UtilityA
B
2045

Removal

2400

1,500

Φ3,050

RemovalA

Access tunnel
Transportation cart (Lift section)

B

□150

Equipment hatch

B-B

Connection sleeve

Maximum dimensions for being
able to pass through (mm)Turning around(Rotating 90°)

A-A

Results of the study on dimensions related to inserting the equipment inside the PCV

The dimensional constraints for the equipment to pass through the route (access tunnel connection
sleeve equipment hatch) for entering inside the PCV from outside the building are considered to beaccording to the table on the right.

Width

1000

Length2400

Height1500©International Research Institute for Nuclear Decommissioning

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.166① HVH disassembly◼
Equipment limitations and dimensions (2/2)➢ On comparing with the access route from the front of the equipment hatch (inside PCV) to the HVH, it was found that HVH-C was themost cramped in Units 1, 2 as well as 3. The access location of the equipment at the time of HVH disassembly is indicated below.
➢ The width of the grating in front of the PLR pump in Unit 1 is approx. 1000mm. The grating between the bases in front of the PLR pump in
Units 2/3 is approx. 860mm. These become the main dimensional constraints in the lateral direction.
➢ The terminal box of the PLR pump in Unit 1 will be removed as required considering the space for the HVH disassembly work.
➢ The width of the grating in front of the PLR pump in Units 2/3 is considered to be a constraint. However, as the height of the bases andgrating is almost the same, a crawler unit is expected to be able to cross over, and thus with a width of approx. 860mm the dimensional
constraint is expected to have some margin.
PLR pump terminal box(Removed in some cases)

Base(Same height as the grating)
Motor

Motor

BlowerBlowerAccess location of the equipment

Maximum dimensions of
the equipment (mm)
Access location of the equipment at thetime of disassembling HVH-C in Unit 1

Access location of the equipment at the timeof disassembling HVH-C in Unit 3

Based on the width limitations, the dimensional constraints of the HVH disassembly equipment areconsidered to be according to the table on the right.

Width

800

Length2400

Height1500©International Research Institute for Nuclear Decommissioning

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.167① HVH disassembly◼ Dimensions of the disassembled pieces and the container in which the pieces are transported➢ The container and equipment for transferring the disassembled pieces generated when the HVH is disassembled
outside the PCV are given below.

External
dimensions

Internal
dimensions

Details

Carrying-in/out equipment

Waste collection container

Width: 800mm
Length: 1000mm
Height: 1500mm (or less)
The width and height are kept such that the equipment canaccess up to the HVH from the front of the equipment hatch
and the length is kept the same as the waste collection
container.

Width: 800mm
Length: 1000mm
Height: 800mm
Dimensions are determined considering the specifications of
the work cell in the additional building and making sure it canbe enclosed in the waste storage container.

Width: 760mm
Length: 960mm
Height: 250mm (or more)

Width: 760mm
Length: 960mm
Height: 780mm

The disassembled pieces generated when the HVH is cut,will be stacked in the disassembly work space, andtransported remotely to the front of the equipment hatch bymeans of a crawler, etc.

The pieces will be transported from the additional building to
the equipment hatch by means of the access tunnel
transportation cart that travels inside the access tunnel. The
disassembled pieces will be received from the transfer
equipment at the front of the equipment hatch and stored.

Based on this, it was decided to keep the dimensions such that the disassembled pieces can be transported in
760x960x250 (or more) mm containers.
©International Research Institute for Nuclear Decommissioning

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]① HVH disassembly◼ Preconditions [Selecting the HVH to be disassembled]➢ Results of evaluating HVH-A to E in Units 1, 2, 3 are given below.
Accessibility up to HVH
U
ni
t

HVH
No.

Length of the route

Number of bends

1

HVH-A

Approx. 21 m [x]

2

HVH-B

No.168[Legend] Level of difficulty:
Difficult (×), Easy (○)

Work space

Viability of transfer work

Number of level
differences or slopesthat will have an
adverse impact ontransfer

Comprehensive evaluation
Difficulty level: High /Medium / Low(Number of instances
evaluated as x) (*)

Number ofinterfering objects
that are difficult toremoveWork locationof the robot(*)

Ratio to the φ800 work
space at the time ofdisassembling HVH

Ratio to the φ800 work
space at the time ofremoving HVH

3 locations [x]0 location [〇]Long [○]

2.2 [〇]

2.2 [〇]

0 location [〇]Level of difficulty: High (x:2)

Approx. 18m [〇]2 locations [x]0 location [〇]Long [○]

1.8 [〇]

1.8 [〇]

0 location [〇]Level of difficulty: Medium(x: 1)

HVH -CApprox. 13 m [〇]1 location [x]0 location [〇]Short [×]1.5 [〇]

1.5 [〇]

0 location [〇]Level of difficulty: High(×: 2)

4

HVH-D

Approx. 4m [〇]0 location [〇]0 location [〇]Long [○]

3.0 [〇]

3.0 [〇]

0 location [〇]Level of difficulty: Low (x:
0)

5

HVH-E

Approx. 7 m [〇]0 location [〇]0 location [〇]Long [○]

2.0 [〇]

2.0 [〇]

0 location [〇]Level of difficulty: Low (x:
0)

6

HVH-A

Approx. 12 m [〇]0 location [〇]0 location [〇]Long [○]

2.6 [〇]

2.6 [〇]

0 location [〇]Level of difficulty: Low (x:
0)

7

HVH-B

Approx. 10 m [〇]0 location [〇]0 location [〇]Long [○]

1.9 [〇]

1.9 [〇]

0 location [〇]Level of difficulty: Low (x:0)

HVH -CApprox. 5 m [〇]0 location [〇]0 location [〇]Long [○]

1.2 [×]1.2 [×]0 location [〇]Level of difficulty: High (x:
2)

9

HVH-D

Approx. 15 m [〇]1 location [×]0 location [〇]Long [○]

2.0 [〇]

2.0 [〇]

0 location [〇]Level of difficulty: Medium(x: 1)10

HVH-E

Approx. 18 m [〇]2 locations [×]0 location [〇]Long [○]

1.9 [〇]

1.9 [〇]

0 location [〇]Level of difficulty: Medium(x: 1)

Approx. 20 m

0.9 location

0 location

―

1.5

1.5

0 location

―

No.

3

8

1

2
3

Reference value oraverage 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 are highlighted yellow in the table.
As the level of difficulty is evaluated as 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：Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).
(*) The work location of the robot was added to the line items for evaluating the level of difficulty of disassembling HVH in Units 1, 2/3.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.169① HVH disassembly◼ Issues at the time of disassembling HVH➢ The structure of HVH and the sites that need to be cut for removal are given below.

Duct

Cold air

Bolt

Damper

Motor

Electrical wire

Welding
Cooling
water pipe

Blower

Welding(Beam)

Filter

Cooling coil

Illustration of fixing
memberMember for fixing
to the beam

Hot air

Cooling water

Drainage pipe

Fixing member
Beam

DamperDrainage

Grating

Sites that need to be cut for removal(Structures such as fixing members, etc. that are not shownin the outline drawing are assumed based on Unit 1.)

For disassembling and removing the HVH, in addition to cutting the damper, connecting pipes, electrical wires and fixing members,
heavy weight motors and blowers installed at high altitudes need to be removed, and heavy weight cooling coils that have a complex
structure need to be removed as well.
HVH disassembling work steps are studied based on this.
©International Research Institute for Nuclear Decommissioning

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

No.170

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]① HVH disassembly◼
Status after disassembling HVH➢ It is assumed that the HVH is installed on the grating and is affixed to the radial beam by fastening bolts or
fixing members.
➢ It is assumed that the fixing member is welded to the beam. So the fixing member will be cut at the surfaceof the grating.
➢ It is assumed that the bolt hole made in the shim welded on the beam and the frame are fastened with abolt. Hence the bolt head will be cut. Also, the frame will be cut if required to secure work space for cutting
the bolt.
➢ Since the work of removing the fixing member or the bolt will be carried out after removing the main HVH,
work space can be secured and thus the level of difficulty is low. Hence this work is assumed to be easier ascompared to the work of removing the main HVH.

Frame
Robot arm

Illustration of the cutting of the clamp(In the case of fixing member)

Beam

Grating

Cutting position
Bolt (M18)

Illustration of the cutting of the bolt
(In the case of fastening with bolts)

Shim and bolt hole

Beam

After disassembling and removing HVH, there will be remnants of about 10mm on the grating.
The robots and equipment are assumed to have a crawling functionality and are expected to cover the entire distance.
©International Research Institute for Nuclear Decommissioning

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

About 10mm

About 10mm

Cutting position

Cutting position

About 32mm

Removed if it interferes
when the bolt is cut

109mm
Grating

Robot arm

Circular saw

Circular saw

Bolt (M16)

Removed if it interferes
when the bolt is cut

Frame

150mm

Fixing member

Illustration before
cutting the HVH

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.171① HVH disassembly◼ Definition of tests

Unit test

Element test

Cut with the arm extended.
FixingFixingTest image

To be cut•

Surrounding
environment

•
•

•

Frame

The cutting test is conducted in a brightenvironment without using simulated PCV.
Only the HVH disassembly robot is used
Cutting is performed under rigid conditions with thearm of the HVH disassembly robot extended.
The robot is operated while visually confirming.

•••

Cutting
Target

The cutting test is conducted by affixing members thatare equivalent to the structural components of HVH, on
to the frame.

The cutting test is conducted in an environment simulating
the surrounding interfering objects or darkness, inside thesimulated PCV where the on-site decommissioning
environment is simulated.
The HVH disassembly robot, the assist robot, carrying-in/out
equipment and the crane are linked and the operation is
performed.
Cameras and lights are placed, and they are operated
remotely.

The cutting test is conducted using simulated HVH in which thedimensions and material of the main components are simulated.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.172① ＨＶＨ disassembly◼ Element test items (1/3)➢ The test items for the unit tests and the element tests are selected from the work steps in disassembling HVH, which were studied.
The test items selected and the reason for selection are given below.
Work
Step

Unit test
Details

Element test

Necessity

ReasonNecessity

ReasonNot
requiredThis test is not required as traveling is assumed to be bymeans of a crawler, and the traveling test has been
conducted during the development of the robot to be
used outside the pedestal inside the PCV in the past.

Not
requiredThis is similar to ⑥ and ⑦. As it will be verified in ⑥ and⑦, this test is not required.

RequiredThis test is required for verifying the viability of the
cutting work and work of collecting disassembled pieces
carried out at high altitudes using the HVH disassembly
robot, and the access for the cutting tools.

① Access for the cutting
equipment

Traveling of robot

Not
requiredThis test is not required as traveling is assumed to
be by means of a crawler, and the traveling test has
been conducted during the development of therobot to be used outside the pedestal inside thePCV in the past.

② Cutting of connecting
pipes

Cutting the pipes

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

RequiredThis test is required for verifying the conditions inwhich cutting is possible by means of mechanicalcutting method using a circular saw, wire saw, etc.

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

RequiredThis test is required for verifying the viability of the
cutting work and work of collecting disassembled pieces
carried out at high altitudes using the HVH disassembly
robot, and the access for the cutting tools.

NotrequiredThis is similar to the work carried out in ④. As it will
be verified in ④, this test is not required.

Required(Addition)

This test is required for verifying the viability of the
cutting work and work of collecting disassembled pieces
carried out at high altitudes using the HVH disassembly
robot, and the access for the cutting tools.

Cutting the eye bolt
Cutting the terminal box

Not
requiredThis is similar to the work carried out in ④. As it will
be verified in ④, this test is not required.

Not
requiredThis is similar to the work carried out in ④. As it will beverified in ④, this test is not required.

Cutting the electrical wireNot
requiredThis test is not required as there is a proven trackrecord of cutting from tests in the past.

Not
requiredThis test is not required as there is a proven trackrecord of cutting from tests in the past.

③ Cutting of the damper

Cutting the damper④ Cutting of the panels of
the blower unit

Cutting the cutting frame([100) of the panel
Cutting the cutting frame([100) of the panel⑤ Cutting of the counter top

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.173① ＨＶＨ disassembly◼ Element test items (2/3)
Work

Step

Unit test

Details⑥ Slinging of heavy objects

Slinging using a motor

Necessity

Not
required

ReasonThis test is not required as there is a proven trackrecord of slinging from tests in the past.

Element test

Necessity

ReasonThis test is required for verifying the viability of slinging
work carried out by combining HVH disassembly robot
and hoisting equipment for the HVH-C in Units 2/3.

RequiredThis test is required for verifying the viability of slinging
work carried out by combining the assist robot andhoisting equipment for the HVH-C in Unit 1.
This test is required for verifying the viability of cutting
work carried out by combining HVH disassembly robot
and hoisting equipment for the HVH-C in Units 2/3.
This test is required for verifying the viability of accessfor the cutting tools.

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc. This test is required formaking sure that the blade of the cutting equipment
does not get caught while cutting.

Delivering heavy objects tothe transfer equipment

RequiredThis test is required for verifying whether or not theheavy object can be hoisted by means of the
hoisting equipment.

RequiredThis test is required for verifying whether or not theheavy object can be hoisted by means of the hoisting
equipment without interfering with surrounding
structures in confined spaces.

Cutting the blower caseCutting the impeller shaft
Cutting the shaft bearing

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

RequiredThis test is required for verifying the viability of the
cutting work and work of collecting disassembled pieces
carried out at high altitudes using the HVH disassembly
robot, and the access for the cutting tools.

⑦ Cutting of the base ofheavy objects

Cutting the base of the
motor ([125)Cutting the motor shaft⑧ Hoisting and delivery ofheavy objects⑨ Cutting of heavy objects(blower)

RequiredNote: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

This test is required for verifying the viability of cutting
work carried out by combining the assist robot andhoisting equipment for the HVH-C in Unit 1.
This test is required for verifying the viability of accessfor the cutting tools.
Also, as the structure of the HVH-C in Units 2/3 and the
motor base is different, this test is required for verifying
whether the cutting equipment can access in the samemanner.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.174① HVH disassembly◼ Element test items (3/3)
Work
Step

Unit test
Details⑩ Cutting and removal of theblower unit

⑪ Cutting and removal of thecoil unit

Element test

Necessity

ReasonNecessity

ReasonCutting the frame ([150)
Cutting the bolt (M12)RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

Not
requiredThis is similar to the work carried out in ④. As it will beverified in ④, this test is not required.

Cutting the panel
Cutting the frame([125,100)

Not
requiredThis is similar to ④ and ⑦. As it will be verified in④ and ⑦, this test is not required.

Not
requiredThis is similar to ④ and ⑦. As it will be verified in ④ and⑦, this test is not required.

Cutting the cooling coil

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

RequiredThis test is required for verifying the viability of the
cutting work and work of collecting disassembled pieces
carried out in confined spaces using the HVH
disassembly robot, and the access for the cutting tools.

Cutting the filter and wire
mesh

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

Not
requiredThis is similar to the work carried out in ④. As it will beverified in ④, this test is not required.

Cutting the pipes and flange

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

Not
requiredThis is similar to ⑦ and ⑨. As it will be verified in ⑦ and⑨, this test is not required.

Cutting the panel
Cutting the frame ([150),
[100)

Not
requiredThis is similar to ④ and ⑩. As it will be verified in④ and ⑩, this test is not required.

Not
requiredThis is similar to the work carried out in ④. As it will beverified in ④, this test is not required.

Cutting the drain pan

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

Not
requiredThis is similar to the work carried out in ④. As it will beverified in ④, this test is not required.

Cutting the clamp

RequiredThis test is required for verifying the conditions inwhich cutting is possible using a circular saw,
reciprocating saw, etc.

Not
requiredThis is similar to the work carried out in ④. As it will beverified in ④, this test is not required.

A test plan will be drafted for the unit tests and element tests that are determined to be required.

Note: Cited from the results of the studies outsourced to TEOCO HD (Implemented in FY2020-21).

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.175① HVH disassembly◼
Scope of simulation in element tests (Test equipment)➢ Access for the equipment: It is assumed that the HVH disassembly robot, the crane and the carrying-in/out equipment have alreadyaccessed the HVH from the equipment hatch.
➢ Structure of the crane: A jib crane that can simulate the scope of movement of the roughter crane that will be used for the actual HVH.
➢ Environment inside the PCV: From among the structures that lie in the work area, the external form of the PLR motor that cannot be
removed is simulated.
From among the structures that lie in the work area, the MS drain pipes, support, etc. are assumed tohave already been removed.
The area where the grating is laid is simulated, and the placement locations of the robot and equipment
are simulated.
Black-out curtain is used to simulate darkness similar to the actual conditions.
Simulated
HVH

PLR motor
PLR motor(Only external
form is simulated)

HVH
disassembly
robot

HVH

Crane
(For the test)

Actual layout of the HVH and PLR pump in Unit 3
Structures for which external form
is partially simulated

HVH

Illustration of the simulation for the element test
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.176① HVH disassembly◼
Scope of simulation in element tests (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 tothe damper, upper panel, upper frame, etc. Hence the lower surface of the duct is simulated.
Note that the dimensions of the area between the top of the HVH and the lower surface of the duct issimulated 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
equipment.
In order to verify repetitive works, approx. 1/6th of the main body is simulated for verifying typical work.

Lower surfaceof the duct
DamperUpper frame
BlowerUpper panel

Motor

Frame
Panel

Cooling coil

Actual HVH (assumed)

Simulated HVH

Simulated HVH (without the panels)©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.177① HVH disassembly◼ Main robot used: HVH disassembly robot

GripperArm
fixtureOverview of HVH disassembly robot

Parts of the arm that can move

Arm being test manufactured (one arm)

Specifications

Functions and remarks

L1480×W740×H1350mm(while moving)

Dimensional constraints from the access tunnel to the equipment hatch: Dimensions such that the equipment can passthrough D1000×H1500×L2400mm
The scope of movement of the arm is such that it can cut and remove structures installed on top of the HVH (H2500mm).

Work arm with 10 shafts x 2

One arm grabs and operates the cutting tools. 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.

Portable weight of the workarm

Approx. 20kg/arm

Weight with which the cutting tools and disassembled pieces can be grabbed, moved and operated.

Weight of the equipment

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

Selected considering radiation resistance.

Equipment dimensions

Structure

Use

Power

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.178① 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)

Overview
diagramLegs for moving(detached)Specifications

Explanation

Power: hydraulic pressure
External dimensions: L1503×W463×H575mm
Mass: approx. 100kg

Power: Electric power
External dimensions: L3750×W920×3148mm
Mass: 490kg

Power: None
Internal dimensions: L960×W760×H330mm
External dimensions: L1000×W800×H732mm
Mass： approx. 90kg
Loaded： 400kg or more

A multi-legged assist robot developed in the past isused. It assists in removing hoisting equipment,
handling the cable hose, etc. with both work arms.

It is installed on the grating or the beam of thesimulated PCV. During the element test, the scope of
movement of the roughter crane that is planned to be
used on the actual site, is simulated and the work ofhoisting and delivering is verified.

The disassembled pieces of HVH will be received andtransported up to the equipment hatch. As the driving
test is not to be conducted during the element test,
the external form of the portion that will be collected
and the portion that will be driven is simulated and thework up to collection is verified.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.179① HVH disassembly◼ Cutting tools associated with the work of disassembling and removing the HVH
Tip saw

HydrauliccylinderMotor

Centerless tip saw

Blade

Grindstone grinder

Motor

Verticaldirection
垂直方向

Grindstone

Motor

Overview
diagram

Vertical direction
垂直方向
HydrauliccylinderSpecifications

TargetExplanation

Horizontal
direction
水平方向
Blade

HydrauliccylinderHydrauliccylinderVertical direction
垂直方向

Power: Electric power / hydraulic pressure (stroke)
External dimensions: 323×214mm
Stroke*1: Vertical 75, Horizontal 200mm
Mass: 12kg
Portable Weight: Approx. 20kg/arm

Power: Electric power / hydraulic pressure (stroke)
External dimensions: 248×144×586.5mm
Stroke*1: Vertical 200mm
Mass: 14kg

Power: Electric power / hydraulic pressure (stroke)
External dimensions: 38.2×150×548mm
Stroke*1: Vertical 175mm
Mass: 14kg

Damper, panel,casing (blower)

Frame, cooling coil

Motor shaft, blower shaft, motor base

The tip saw is operated with 2 strokes, and cutting is
performed in a straight line.

The blade of the tip is processed so that there is no
center shaft, and the distance over which the object tobe cut can be pushed in is increased. It is used to cut[150 channels or block shaped cooling coils that
require a long stroke.

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.

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6. Implementation items of this project [1) (2) Development of disassembly and removal technology]① HVH disassembly◼ Cutting procedure of the cutting tool (Tip saw)
➢ The tip saw cuts with a horizontal and vertical stroke.
As one side of the duct or panel cannot be cut in the 1st round of work, it
is cut in the 2nd round of work.
And, this is repeated for each side to cut one surface of the duct or
panel.
➢ The HVH disassembly robot pushes the cutting tool against the object
to be cut to position it, and object is cut when the cutting tool operates(rotation, stroke).

Horizontal stroke
Cuttingline 1

To be cut

Vertical stroke(Cutting)

Cuttingline 2Cuttingline 3Cuttingline 5

Cuttingline 6

Cuttingline 4

Cuttingline 7

Alignment

No.180

Horizontal stroke(Cutting)

Cuttingline 8

Vertical stroke(End of cutting)Blade

Tip saw
Component for
pushing the tool
against the object
to be cutCuttingline 1

Repeating theprocedure fromalignment©International Research Institute for Nuclear DecommissioningNo.181

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]① HVH disassembly◼ Cutting procedure of the cutting tool (Centerless tip saw and grindstone grinder)➢ The centerless tip saw and the grinstone grinder cut with a vertical stroke.
As the horizontal stroke is not used, and cutting is carried out only with a verticalstroke, these tools are used for cutting frames, shafts, etc. that are thick.

Vertical stroke
Width of the cut
Blade➢ The HVH disassembly robot pushes the cutting tool against the object to be cut toposition it, and object is cut when the cutting tool operates (rotation, stroke).

Blade(After the stroke)

Alignment

Vertical stroke(Cutting)

Horizontal stroke(Cutting)

HandleVertical stroke(End of cutting)

To be cutCenterless tip saw
Grindstone grinder―Component for
pushing the tool
against the object
to be cut

Blade©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.182① HVH disassembly◼ Jigs associated with the work of disassembling and removing the HVH
Motor hoisting jig

Impeller hoisting jig

Sliding unit

Hoisting jig : 20kg

Overview
diagram

Impeller: 110kg

Sling wire

Motor pad

Specifications

TargetExplanation

Power: None
External dimensions： (Detailed study
underway)
Mass： (Detailed study underway)

Power: None
External dimensions： (Detailed study
underway)
Mass： (Detailed study underway)

Motor

Impeller

Used for slinging the motor when it cannot behung on the hook of the crane or when there
is no eye bolt on the motor.

Used for slinging the impeller.

©International Research Institute for Nuclear DecommissioningNo.183

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]① HVH disassembly◼
Dimensional constraints associated with disassembly and removal work
➢ Dimensional constraints and the movement of the disassembled pieces is shown in the figure below (The figure below illustrates
Unit 3 HVH-C, but work pertaining to other HVH is also the same).
Dimensional constraints
on the access route:
W 800
H1500

Dimensional constraints of theequipment hatch and access tunnel:
W1000
L2400
H1500

Carrying-in/out
equipment

HVH

Disassembled
piecesDisassembled
piecesEquipment
hatch

Waste collection container:
External
Internal
W800
W760
L1000
L960
H800
H780
Access tunnel

Dimensions ofdisassembled pieces：
W760 or less
L960 or less
H780 or less

Bird’s eye camera

Disassembled
piecesDisassembled
piecesUtility line bird’s eye camera
Carrying-in/out
equipment
Waste collection
container

Layout drawing of Unit 3
HVH-C

Large robot

HVH
disassembly
robot

Carrying-in/out equipment
dimensions:
External
Internal
W800
W760
L1000
L960
H732
H330

Unit： mm©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.184① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the damper
DamperStep
figureDetails

The cutting tool will access the damper, cut the damper, grab the disassembled pieces and deliver them to the carrying-in/out equipment using the
HVH disassembly robot.
As cutting and removal will be carried out sequentially starting from right in front of the HVH disassembly robot, the damper will be removed.
The stroke of the tip saw is not sufficient for the length of 1 side of the disassembled pieces. Hence cutting is performed by overlapping cutting lines.

Cutting
tools

Tip saw

Issues•••Cutting work at high altitude locations
Grabbing the disassembled pieces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.185① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the panel
Cuttingline 1
Cuttingline 2

Step
figureTip saw
Panel

Details

The cutting tool will access the panel, cut the panel, grab the disassembled pieces and deliver them to the carrying-in/out equipmentusing the HVH disassembly robot.
The stroke of the tip saw is not sufficient for the length of 1 side of the disassembled pieces. Hence cutting is performed by overlapping
cutting lines.

Cutting
tools

Tip saw

Issues•••Cutting work at high altitude locations
Grabbing the disassembled pieces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.186① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the frame
Cuttingline 1

Step
figureCenterless tip saw

Frame
Frame
Cuttingline 2

Details

The cutting tool will access the frame, cut the frame, grab the disassembled pieces and deliver them to the carrying-in/out equipment using the HVH disassembly
robot.
Both ends of the frame will be cut and disassembled with a centerless tip saw.

Cutting
tools

Centerless tip saw

Issues•••Cutting work at high altitude locations
Grabbing the disassembled pieces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.187① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the upper panel
Upper
panel

Cuttingline 2

Step
figureTip saw

Cuttingline 1

Details

The cutting tool will access the upper panel, cut the upper panel, grab the disassembled pieces and deliver them to the carrying-in/out
equipment using the HVH disassembly robot.
The stroke of the tip saw is not sufficient for the length of 1 side of the disassembled pieces. Hence cutting is performed by overlapping
cutting lines.

Cutting
tools

Tip saw

Issues•••Cutting work at high altitude locations
Grabbing the disassembled pieces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.188① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the upper frame
Centerless tip saw
Frame

Step
figure

Frame

Frame

Details

The cutting tool will access the frame, cut the frame, grab the disassembled pieces and deliver them to the carrying-in/out equipmentusing the HVH disassembly robot.
Both ends of the frame will be cut and disassembled with a centerless tip saw.

Cutting
tools

Centerless tip saw

Issues•••Cutting work at high altitude locations
Grabbing the disassembled pieces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.189① HVH disassembly◼ Element test plan (Test items)
Work
step

Installing the motor hoisting jig
Simulated PLR
motor(Only external
form is simulated)

Hoisting
jig

Sliding unit

Step
figureSling wire
Crane
(For the test)

Motor

Motor pad

Details

The motor hoisting jig that is lifted up with the hook of the crane will be slung using the HVH disassembly robot.

Cutting
tools

―
•
•

Coordination of the work of the HVH disassembly robot and the crane in a confined space
Placement of the lights and camera for monitoring work

Issues©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.190① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the motor shaft / base
Grindstone
grinder

Grindstone
grinder

Grindstone
grinderStep
figureHoist(For the test)

Motor

Motor
shaft

Motor baseMotor baseDetails

The cutting tool will access the motor shaft and base and cut them using the HVH disassembly robot.
The motor shaft will be cut before the previous step of “Installing the motor hoisting jig”, but for the sake of explanation it has
been included in this step.

Cutting
tools

Grindstone grinder

Issues•••Cutting work in confined spaces
Interference in the work of the crane and hoisting jig
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.191① HVH disassembly◼ Element test plan (Test items)
Work
step

Lifting up / delivering the motor
Motor
delivery location

Travel
route

Motor

Motor
deliverylocationStep
figureCarrying-in/out
equipment
Hoist(For the test)

Hoist(For the test)

HVH disassembly
robot

Details

The motor will be lifted up and delivered to the carrying-in/out equipment using a crane, and will be released from the hook of the
hoisting jig using the assist robot.

Cutting
tools―

Issues••••Interference with the remnant structures of the HVH
Interference with the structures in the surrounding (PLR motor)
Whether or not the work can be carried out using the assist robot
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.192① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the casing (blower)

Step
figureImpeller
BlowerDetails

The cutting tool will access the casing, cut the casing, grab the disassembled pieces and deliver them to the carrying-in/out equipmentusing the HVH disassembly robot.

Cutting
tools

Tip saw

Issues•••Cutting work at high altitude locations
Grabbing the disassembled pieces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.193① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting of impeller (blower)
Hoisting jig(Sling, etc. is assumed)

Step
figureImpeller
Hoist(For the test)

Details

The cutting tool will access the impeller using the HVH disassembly robot, the impeller hoisting jig that is lifted up with thecrane will be slung using the HVH disassembly robot and the impeller shaft will be cut.

Cutting
Tools

Grindstone grinder

Issues•••Coordination of the work of the HVH disassembly robot and the crane in a confined space
Cutting work in confined spaces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear DecommissioningNo.194

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]① HVH disassembly◼ Element test plan (Test items)
Work
step

Lifting up and delivering the impeller (blower)
Impeller
Impeller

Hoist(For the test)

Impellerdelivery location

Travelroute

Impellerdelivery location

Step
figureCarrying-in/out
equipment

Hoist(For the test)

HVH disassembly
robot

Details

The impeller will be lifted up and delivered to the carrying-in/out equipment using a crane, and will be released from the hook of the
hoisting jig using the assist robot.

Cutting
Tools―

Issues••••Interference with the remnant structures of the HVH
Interference with the structures in the surrounding (PLR motor)
Whether or not the work can be carried out using the assist robot
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.195① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the cooling coil
Divided into
blocksCenterless tip saw

StepfigureCoolingcoil
Coolingcoil

Details

The cutting tool will access the cooling coil, cut it, grab the disassembled pieces and deliver them to the carrying-in/out equipment using
the HVH disassembly robot.

Cutting
tools

Centerless tip saw

Issues•••Cutting of complex structures
Grabbing the disassembled pieces
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.196① HVH disassembly◼ Element test plan (Test items)
Work
step

Cutting the motor shaft / base (Unit 1)
Simulated PLR
motor(Layout in Unit 1)

Hoist(For the test)

Simulated HVH(Common with
Unit 3)

Area with restrictedmovement(Area in Unit 1 is simulated)

IssuesTravel
route

Motor

Motor
delivery location

Step
figureDetails

Motor
delivery location

Carrying-in/out
equipment

Hoist(For the test)

The motor will be lifted up and delivered to the carrying-in/out equipment using a crane, and will be released from the hook of the
hoisting jig using the assist robot.
••••

Interference with the remnant structures of the HVH
Interference with the structures in the surrounding (PLR motor)
Whether or not the work can be carried out using the assist robot
Placement of the lights and camera for monitoring work

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.197① HVH disassembly◼ Element test plan (Test items)
Work
step

Arrangement of cameras and lights (example of cutting the damper)
CameraCamerainstallation
installation location
location

HVH

Camer
Camera
a

View
angle

CameraStep
figureView
angle

Details

Large
robot

Camerainstallation
location

Extensionpole

It will be verified whether or not the visibility required for work can be secured with the arrangement of cameras and lights considered
beforehand, at each work step.
The placement of the cameras will be moved or cameras will be added as required upon consultation with the operator.
••

IssuesCarrying-in/out
equipment•

Capturing of images that can facilitate work
Verification of whether or not surrounding structures interfere with the HVH disassembly robot and equipment using a bird's eye
cameraSecuring of the visibility required for the operator to carry out work by means of the cameras mounted on the HVH disassembly
robot and other local cameras.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.198① HVH disassembly◼ Element test plan (Test items)
Work
step

Arrangement of cameras and lights (example of lifting up and delivering the motor)
Small
robot

Camerainstallation location

HVH

Extension
pole

CameraView
angle

CameraStep
figureCamerainstallation location

Details

Hoist

Large
robot

Camerainstallation location

It will be verified whether or not the visibility required for work can be secured with the arrangement of cameras and lights considered
beforehand, at each work step.
The placement of the cameras will be moved or cameras will be added as required upon consultation with the operator.
••

IssuesCarryingin/out
equipment•

Capturing of images that can facilitate work
Verification of whether or not surrounding structures interfere with the HVH disassembly robot and equipment using a bird's eye
cameraSecuring of the visibility required for the operator to carry out work by means of the cameras mounted on the HVH disassembly
robot and other local cameras.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.199① HVH disassembly◼ Element test items and judgment criteria
No.

1

2

3

4

5

6

Test Item

Cutting the damper

Cutting the panel

Cutting the frame

Cutting the upper panel

Motor removal

Removal of the casing
part

Test details
Target cutting work will be performed using the HVH
disassembly robot to verify whether or not the work
can be performed remotely.

Target cutting work will be performed using the HVH
disassembly robot to verify whether or not the work
can be performed remotely.

Target cutting work will be performed using the HVH
disassembly robot to verify whether or not the work
can be performed remotely.

Target cutting work will be performed using the HVH
disassembly robot to verify whether or not the work
can be performed remotely.

Target cutting work will be performed using the HVH
disassembly robot to verify whether or not the work
can be performed remotely.
It will be verified whether or not the work of lifting up
and delivering by means of a crane can be
performed remotely.

Target cutting work will be performed using the HVH
disassembly robot to verify whether or not the work
can be performed remotely.

Judgment criteria
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫
⚫

The cutting tools should be able to access the target and perform cutting.
It should be possible to grab and deliver the disassembled pieces to the carrying-in/out
equipment.
The HVH disassembly robot should not get turned over.
Time required for work should be recorded.
The cutting tools should be able to access the target and perform cutting.
It should be possible to grab and deliver the disassembled pieces to the carrying-in/out
equipment.
The HVH disassembly robot should not get turned over.
Time required for work should be recorded.
The cutting tools should be able to access the target and perform cutting.
It should be possible to grab and deliver the disassembled pieces to the carrying-in/out
equipment.
The HVH disassembly robot should not get turned over.
Time required for work should be recorded.
The cutting tools should be able to access the target and perform cutting.
It should be possible to grab and deliver the disassembled pieces to the carrying-in/out
equipment.
The HVH disassembly robot should not get turned over.
Time required for work should be recorded.
The cutting tools should be able to access the target and perform cutting.
It should be possible to grab and deliver the disassembled pieces to the carrying-in/out
equipment.
It should be possible to sling the motor to the hoisting jig by means of the HVH disassembly
robot.
The structures in the surrounding should not come in contact when the motor is lifted up.
It should be possible to remove the hoisting jig from the hook of the crane using an assist
robot.
The HVH disassembly robot and assist robot should not get turned over.
Time required for work should be recorded.
The cutting tools should be able to access the target and perform cutting.
It should be possible to grab and deliver the disassembled pieces to the carrying-in/out
equipment.
The HVH disassembly robot should not get turned over.
Time required for work should be recorded.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.200① HVH disassembly◼ Element test items and judgment criteria
No.

Test Item

7

Impeller removal

8

9

10

Removal of cooling
coil

Installation ofcameras andverification of visibility

Installation of lights
and verification ofvisibility

Test details
Target cutting work will be performed using the
HVH disassembly robot to verify whether or not
the work can be performed remotely.
It will be verified whether or not the work oflifting up and delivering by means of a crane
can be performed remotely.

Target cutting work will be performed using the
HVH disassembly robot to verify whether or not
the work can be performed remotely.

Cameras will be installed using the HVH
disassembly robot and the obtained images will
be verified.

Lights will be installed (lights integrated with thecamera are assumed) using the HVH
disassembly robot, and the camera images
captured when the lights are put on will beverified.

Judgment criteria⚫
The cutting tools should be able to access the target and perform cutting.
⚫
It should be possible to grab and deliver the disassembled pieces to the carryingin/out equipment.
⚫
It should be possible to sling the impeller to the hoisting jig by means of the HVH
disassembly robot.
⚫
The structures in the surrounding should not come in contact when the impeller islifted up.
⚫
It should be possible to remove the hoisting jig from the hook of the crane using an
assist robot.
⚫
The HVH disassembly robot and assist robot should not get turned over.
⚫
Time required for work should be recorded.
⚫
The cutting tools should be able to access the target and perform cutting.
⚫
It should be possible to grab and deliver the disassembled pieces to the carryingin/out equipment.
⚫
The HVH disassembly robot should not get turned over.
⚫
Time required for work should be recorded.
⚫
It should be possible to capture images that can facilitate work.
⚫
The bird's eye camera should be able to verify whether or not surrounding
structures interfere with the HVH disassembly robot and equipment.
⚫
Cameras mounted on the HVH disassembly robot and other local cameras shouldbe able to secure the visibility required for the operator to carry out work.
⚫
Remote installation should be possible.
⚫
Time required for work should be recorded.
⚫
It should be possible to capture images that can facilitate work.
⚫
Remote installation should be possible.
⚫
Time required for work should be recorded.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly
and removal technology]

No.201① HVH disassembly: 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▼

45Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

12

1

2

Final report▼

1. Conceptual study
2. Element test
planing
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.

3©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly andremoval technology]① HVH disassembly: Summary

No.202➢Results of studies conducted on HVH disassembly concerning the selectionof items to be tested based on the level of difficulty of disassembly, selectionof circular saw and reciprocating saw as the cutting technology, andidentification of element test items based on the disassembly work steps
have been compiled.

➢The work steps were examined in detail, and issues in each of the steps wereorganized.
➢The test equipment such as HVH disassembly robot, crane, etc., and thecutting tools such as tip saw, etc. were studied, and their specifications wereconsolidated.
➢Based on the results of above mentioned studies, the element test plan wasdeveloped, and element test items, judgment criteria, etc. were studied. In the
future, the feasibility of the method of disassembling and removing the HVH
will be verified by element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly
and removal technology]

No.203

Solicitation items are listed.
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 pipesby 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 carrying out 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 and devices will enter inside thepedestal is small, the equipment and devices need to be able to operate in a small anduncertain on-site environment. Moreover, any interference with the CRD housing, etc. which isfound 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 fromfalling. During the development concerning this, upon studying and consolidating therequirements 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.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.204② 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(in-core monitor) housing, etc. were studied, and prospects of these methods being feasible were seen throughelement 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 removal
干渉物撤去装置
equipment

CRD
opening
CRD開口Interfering
干渉物
objectInterfering
干渉物
objectProcessing
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 fueldebris 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6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.205② 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 3Structuresat the top

Structures at the top

Platform (P/F)

Illustration
showing thestatus inside thepedestal

CRD
exchanger

Actual status unknown(Damage over and above that in Unit 3
is estimated)

Intermediate
work stand
Platform (P/F)

Results of
estimation•••

Structures at the
top that havefallen off(CR guide tube)

The inside of the pedestal has not been
investigated.
(The above figure shows sound conditions.)

Deposits
Deposits

The following is 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 the deposits)

The following is 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6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.206② Disassembly of CRD exchanger◼Issues•••••

Ensuring that the disassembly and removal equipment is able to access the area aroundthe CRD exchanger.
Disassembling and removing the CRD exchanger, which is a large structure, using a small
equipment that can be carried in through the CRD opening.
Disassembling and removing the CRD exchanger, which is a large structure, into as large
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 otherstructures) that has fallen and gotten entangled.

◼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 will be designed and test manufactured.
Element tests are planned considering remote operation in limited space.
Simulated test pieces and full scale testing equipment is designed and manufactured
for conducting the tests.
Feasibility of specific disassembly and removal are verified by element tests.

◼Expected outcome•

Presentation of the method of disassembling and removing the CRD exchanger

CRD
opening

Structuresat 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 that havefallen off(CR guide tube)
Deposits

Platform (P/F)

CRD exchanger(Buried under
the deposits)

Figure illustrating the estimated conditions
inside the pedestal (Units 1/3)
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]② Disassembly of CRD exchanger◼ Implementation details (Flow)

No.207

Scope of this report•
Test manufacturing of the transportation equipment equipped with a jib, required in common for Units 1 - 3.
•
Results of verifying whether or not the equipment can be carried in, and the disassembled pieces can be lifted,
loaded and transferred in the simulated Unit 2 environment (Basic test)•
Results of verifying viability of “the rail for the equipment to access target object” and “fall prevention by
fastening with the upper CRD exchanger” required for disassembling and removing the Unit 2 CRD exchanger(Element test)

The flow of the implementation details mentioned on the previous page is indicated below.

Based on Unit 2

Based on Units 1/3

Compilation of various preconditions (including the dimensions etc. of the structures)
Study and compilation of requirements

Study and compilation of requirements

Study of the method of disassembly and removal

Study of the method of disassembly and removal

Identification of common technologies that must be developed
Basic test plan
Designing and test manufacturing of the disassembly and removal equipment (for basic tests), implementation of tests
Designing and test manufacturing of disassembly and removal
equipment (unit specific)

Designing and manufacturing of the disassembly and removal
equipment (unit specific)

Element test planning

Element test planning

Designing and manufacturing of simulated test pieces and full scale
simulated equipment

Designing and manufacturing of simulated test pieces and full scale
simulated equipment

Conducting of element tests, and feasibility verification

Conducting of element tests, and feasibility verification©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.208② Disassembly of CRD exchanger◼Compilation of preconditions (1/10)➢ The preconditions at the time of studing the method of disassembling have been compiled under
the following 6 items based on the site status and information in the drawings.

①
②
③
④
⑤
⑥

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
Specifications of the access route up to the CRD opening and of the interfering objects©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.209② Disassembly of CRD exchanger◼ Compilation of preconditions (2/10) [Specifications of the CRD exchanger [1/3]]

Platform (P/F)
CRD opening

No.

Items

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 the
hoisting carriage

Specifications[Dimensions], [Material][Thickness], [Mass]: Acquired at the stage of designing theactual equipment

Remarks

Intermediate work stand

CRD support structures
CRD exchanger

Buried part of thepedestal bottom

4

1[Dimensions],[Material], [Mass]: Acquired at the stage of designing theactual equipment

2©International Research Institute for Nuclear Decommissioning36. Implementation items of this project [1) (2) Development of disassembly and removal technology]② Disassembly of CRD exchanger

Platform (P/F)◼ Compilation of preconditions (3/10) [Specifications of the CRD exchanger [2/3]]
No.

Items

Specifications

Remarks

5

Rotating
frame[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]• The plate thickness is an
estimate.
• Mass is a rough value.

6

Frame
rotating
equipment[Dimensions], [Material],[Thickness], [Mass]: Acquired at the stage ofdesigning the actual equipment

7

Grabbing
arm[Dimensions], [Material],[Thickness], [Mass]: Acquired at the stage ofdesigning the actual equipment

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]No.210

CRD support structures

CRD opening
CRD exchanger

Intermediate work stand

6

Buried part of thepedestal bottom

7• Dimensions and plate
thickness are estimates.
• Mass is a rough value.

58* Unit 1: Approx. 10 to 20mm.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]② Disassembly of CRD exchanger

Platform (P/F)◼ Compilation of preconditions (4/10) [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 equipment

10

Power supply unit
(Cable bear)[Cable size]: φ25 [mm][Dimensions of connecting plate]
175×50×10t [mm] (U-shaped steel), Length: 540[mm][Material]:
SUS304 (Connecting plate, cable bear)
Aluminum alloy (Cables)[Thickness]: 10 [mm] (Thickness of the connecting
plate)[Mass]:
Cable bear (including the connecting plate): Approx.
about 260 [kg]Cables (on the F/P): Approx. about 20 [kg] per cable• Estimate• There are 10 cable(estimated)• Embedded inside the rotating
frame

11

Other drive units[Dimensions], [Material],[Thickness], [Mass]: Acquired at the stage of designing
the actual equipment

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])No.211

CRD support structures

CRD opening
CRD exchanger

Remarks

Intermediate work standBuried part of thepedestal bottom

9

10

11

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]② Disassembly of CRD exchanger

Platform (P/F)◼ Compilation of preconditions (5/10) [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.

4

Grating[Height]: Maximum 38 [mm]• Estimate• Acceptable maximum load of the grating isassumed to be
250 [kg/m2](This is 50 [%]* of the general strength
indicator specified by the grating
manufacturer.)5

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

No.212

CRD support structures
CRD changer

Remarks

Intermediate work standBuried part of thepedestal bottom

2

1• Estimated from Unit 4
It is assumed that the P/F cannot rotate due
to damage.
• The acceptable maximum load of the P/F isassumed to be the same as that of the grating.
• The P/F and CRD exchanger are assumed
to be fixed. However, the fixation of the P/F isassumed to be unstable (is likely to get
detached due to impact, etc.).

3

4*There are no grounds for 50%. It will be revised if it
is found to be difficult to work with.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]② Disassembly of CRD exchanger

Platform (P/F)

Items

Specifications

1

Opening
G2[Dimensions (as per thedrawings)]
Width: 800 [mm], Depth: 915[mm]•Estimated value

2

Opening
H2[Dimensions (as per thedrawings)]
Width: 800 [mm], Depth: 1,090[mm]•Estimated value

CRD exchanger

Remarks

Intermediate work stand3

Grating

CRD support structures

CRD opening◼ Compilation of preconditions (6/10) [Specifications of the intermediate work stand]No.

No.213[Height]: Acquired at the stage ofdesigning the actual equipment

2

Buried part of thepedestal bottom

14

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6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.214② Disassembly of CRD exchanger◼ Compilation of preconditions (7/10) [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 are listed below.

No.

Interfering
objects

1

TIP guidetube

2

TIP guidetube support

Specifications

Remarks[Outer diameter]:
Φ9.525 [mm][Number of tubes]: 31 tubes[Material]: SUS304-TP•(Unit 4)[Dimensions]:
Height: 75× 75 × t9 [mm](U- shaped steel)
Length: approx. 1,600 [mm](From the top of P/F to the bottom
end: 632.2 [mm])[Mass]: Approx. 25 [kg]
[Number of supports]: 10 - 20
(assumed)[Material]: SUS304 (estimated)•Used only in Unit 2

1
2

Vertical cross section of the CRD exchanger andother structures inside the pedestal©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.215② Disassembly of CRD exchanger◼ Compilation of preconditions (8/10) [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 cutting tools, theCRD exchanger left behind is assumed to be at a height of 360mm* from the surface of the deposits.
If cutting the said site is difficult with the cutting tool specifications, the cutting position will be reviewed separately. But as far as
possible the height from the deposits will be controlled.

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)*Estimate©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.216② Disassembly of CRD exchanger◼ Compilation of preconditions (9/10) [Specifications of the access route up to the CRD opening and of the interfering objects [1/2]]
Equipmenthatch(X-1) 45°

90
°

CRD
opening
37°

180°

0°

90
°

180°

0°

CRD
opening
250°

Equipmenthatch(X-1) 315°

270°

Access route in Unit 1
•
•

270°

Access route in Units 2 and 3

Various equipment will be installed inside the PCV from the equipment hatch, the outer periphery of the pedestal will be traveled using the shortest route (In thelayout drawing, for Unit 1: anti-clockwise, for Units 2/3: clock-wise), to access the CRD opening. This approach will be common for all units.
The opposite sequence of the procedures will be followed for transferring disassembled pieces of the CRD exchanger to the outside of the pedestal through the
CRD opening and to the outside of the PCV through the equipment hatch.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.217② Disassembly of CRD exchanger◼ Compilation of preconditions (10/10) [Specifications of the access route up to the CRD opening and of the interfering objects [2/2]]
No.

Interfering
objectsclassification

Typical dimensions[mm]

Evaluation oflevel of difficulty
in removal

1

Ladder

75×75

Easy

2

Valve

Φ125.7

Cannot beremovedAs it is for RCW piping, based on future usage plan, it is determined that the valve cannot be removed.

3

Supports

150×150×t10 (H steel)

Difficult

As these are supports (legs) for the operation floor, it needs to be examined whether only the supports can be partially removed or theentire operation floor needs to be removed.
If the entire operation floor needs to be removed, as there is large amount of material, the level of difficulty of removing is determined
to be high.

4

Support

150×150×t10 (H steel)

DifficultSame as No. 3.

5

Support

150×150×t10 (H steel)

DifficultSame as No. 3.

6Operation panel

H1, 250×900×200

Easy

Although the thickness of the component material, the fixing method and the overall weight of the panel are unknown, it is assumed
that the panel is comparatively thin. If the overall weight is 400 kg or less, it is assumed that the equipment used for disassemblingand removing the HVH can be used as well.

7

Piping support

200×200×t12 (H steel)

Difficult

As the thickness is more than the [150 channel steel (t6.5), which is the component material of HVH, whether or not the piping support
can be cut and removed needs to be examined separately.

8

Piping support□120

Difficult

Details such as whether the piping support is solid or hollow, its thickness, etc, are unknown. If it is solid, it will be difficult to cut andremove it with a pipe saw, and hence it is determined that equipment exclusively for cutting and removing the piping support will be
required.

9

Support

125×125×t9 (H steel)

DifficultSame as No. 3.

10Support

125×125×t9 (H steel)

DifficultSame as No. 3.

11

Piping support□75

DifficultSame as No. 8.

12Support200×200×t12 (H steel)

DifficultSame as No. 7.

13

Support

150×150×t10 (H steel)

DifficultSame as No. 3.

14

Railing, handrail

30×30

Easy

As the size is comparatively small, it is determined to be easy to remove.

Reason for determining that level of difficulty

It is assumed that a ladder is not planned to be used. As the details of the connection structure at the top end of the ladder are
unknown, it needs to be examined whether the ladder can be partially removed or the entire ladder needs to be removed. As the size
is comparatively small, it is determined to be easy to remove.

The specifications of interfering objects up to the CRD opening are being investigated similarly for Units 1/3 as well.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.218② Disassembly of CRD exchanger◼ Study and compilation of requirements
(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
Platformintermediate work stand beforehand.)(P/F)[Specific to Units 1/3] Structures in the vicinity of the CRD opening must be removed CRD opening
sequentially.
It must be possible to transfer large structures through the CRD opening, and thestructures must be cut into pieces that are as large as possible and then transferred.
(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 tothe 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 thepedestal.
As the integrity of the structures at the top (CRD support structures) inside the pedestal isunknown, 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 useof the wall surface on the left, right and upper side inside the CRD transfer outlet ispossible.)

Requirements with respect to the equipment and tools used
The equipment and tools must be usable under the environmental conditions inside thepedestal (rainfall from the top of the pedestal, darkness, dose rate: 43Gy/h*1 or more).
• Complicated assembly work must not be required to be performed inside the pedestal.
• Cameras and lights must be installed for better visibility during work.

CRD support structures•

Intermediate work standCRD exchanger

Buried part of thepedestal bottom

Illustration showing an overview of theinside of the pedestal (Example of Unit 2)*1) Maximum dose rate outside the pedestal in Unit 2.
(Source: TEPCO website, Results of Internal Investigation of Unit 2 PCV [02/28/2019])©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.219② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal (1/6)
The method and policy for disassembly and removal of the CRD exchanger in Unit 2 and Units 1 and 3 are indicated below.
Unit 2Illustration showing
the status inside thepedestal

Units 1/3

Equipmentat the top

Equipmentat the top

CRDchangerIntermediate
work standDeposits

CR guide tube

CRD exchanger(Buried under thedeposits)

Intermediate work stand
Platform (P/F)

Deposits

Platform (P/F)

The structures in the vicinity of the CRD opening (P/F,intermediate work stand, etc.) will be sequentially removed tosecure work space, and then the CRD exchanger will be
removed.

Disassembly
methodThe 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 toremove the P/F and the intermediate work stand beforehand.)Disassembly policy

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 and 3 are different, but the disassembly policy is the same for all units, in that 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, 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 and 3 are described on the following pages.
In the case of Units 1 and 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.220

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 (2/6) [Unit 2 CRD exchanger disassembly and removal method [1/3])
The work steps (overview) involved in the Unit 2 CRD exchanger disassembly and removal method, which are to be performed inside
the pedestal, are indicated below.

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.)©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.221② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal (3/6) [Unit 2 CRD exchanger disassembly and removal method [2/3])
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.
[Removal ofupper part][Removal oflower part][Removal of upper part]

Transferroute
Fallprevention
tool[Removal ofupper part]

•
•
•
•

The small components (chain, hoisting carriage, etc.) exposed on the surface will be grabbed, cut and removed beforehand by means of a robot, andthereafter, the remaining components will be cut in large pieces that can be transferred through the CRD opening, and removed.
The procedures shown in the above schematic diagram are an example. Considering removal of the cut pieces, securing work space for installing the fall
prevention tool, and reducing the weight of the components that must be prevented from falling, it is desirable to remove the upper CRD exchanger (in theorder of upper part → lower part → upper part) first.
However, it was verified whether or not work can be performed in a confined space (lower part → upper part) during the basic test described later.
The cutting location and removal procedures will be reviewed once the details of the internal structure of the CRD exchanger (dimensions, weight,
whether or not small components will fall during cutting) are clear.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.222② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal (4/6) [Unit 2 CRD exchanger disassembly and removal method [3/3])
The overall work steps (overview) involved in the Unit 2 CRD exchanger disassembly and removal are indicated below.

⑦⑪

⑧⑫
③

90
°

CRD opening
37°

⑥
⑤
⑩

180°

0°

⑨

①
②

④

Equipmenthatch(X-1) 315°

270°

<Overview of work steps>①⑤

Installation of ancillaryequipment outside thepedestal (1/2)②

Installation of ancillary equipment
inside the pedestal(camera, lights, rail, etc.)⑨Preparation forremoval of lower
CRD exchanger(rotating frame) *1⑩

Interference removal
outside the pedestal⑥③

Removal andtransfer ofinterfering objects
inside the pedestal

Lower CRD exchanger(rotating frame)
removal and transfer⑪

Installation of ancillaryequipment outside thepedestal (2/2)⑦

Preparation forremoval of upper CRD
exchanger(2/2)*1) Fall prevention is included in the preparation for removal.

④

Preparation for upper
CRD exchanger
removal(1/2)⑫

Investigation insidepedestal(verification of the statusof damage)⑧

Upper CRD exchanger
removal and transfer(2/2)

Upper CRD
exchanger removal
and transfer(1/2): Common to Units
1 to 3: Specific to Unit 2©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.223② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal (5/6) [Units 1/3 CRD exchanger disassembly and removal method [1/2])
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

Rail

Deposits
Fuel debris① Removal of interfering objects and fallen objects
around the CRD opening

Suctionequipment② Suction of deposits and removal of fallen objects
around the CRD opening③ Installation of rail for equipment access⑤ Removal of objects to be removed (P/F, etc.)⑥ Extension of the rail for equipment access (repeatedhereinafter)

Transportationequipment

Fall
prevention
tool④ Fall prevention measures for the objects to be
removed (P/F, etc.)©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.224② Disassembly of CRD exchanger◼ Study of the method of disassembly and removal (6/6) [Units 1 and 3 CRD exchanger disassembly and removal method [2/2])
The overall work steps*1 (overview) involved in the Units 1 and 3 CRD exchanger disassembly and removal are indicated below.

③

90
°

CRD
opening
37°

⑥’
⑤’

・・・

180°

0°

⑤’

①
②

⑧’⑨’

④

Equipment hatch(X-1) 315°

⑦’

270°

<Overview of work steps>①

Installation of ancillaryequipment outside thepedestal (1/2)⑤’

Installation of ancillary equipment
inside the pedestal(camera, lights, rail, etc.)⑧’

Preparation for removal of
objects to be removed(P/F, etc.) *2②

Interference
removal outside thepedestal

⑥’

⑨’

③

Installation of ancillaryequipment outside thepedestal (2/2)④

Removal and transfer of interfering
objects and fallen objects inside thepedestal

Removal of objects to be
removed (P/F, etc.)*1) The schematic diagram shows Unit 3 as an example*2) Fall prevention is included in the preparation for removal.

Investigation inside pedestal(verification of the status ofdamage)⑦’⑤’ to ⑨’ will be
repeated hereinafter.

Suction of deposits
and removal of fallen
objects: Common to Units 1 to 3
: Specific to Units 1 and 3©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.225② Disassembly of CRD exchanger◼ Identification of common technologies that must be developed
Concept of Unit 2 CRD exchanger disassembly and removal➢ The interfering objects (structures on top of the pedestal) will be removed using a small robot.
➢ The rail for equipment access will be installed on the P/F.
➢ The lower CRD exchanger (rotating frame), which is a hanging structure, will be fastened to the upper CRD exchanger to prevent it fromfalling.
➢ The transportation equipment equipped with a jib will be carried in through the CRD opening, and the CRD exchanger will bedisassembled → lifted up → loaded → transferred.
Concept of Units 1 and 3 CRD exchanger disassembly and removal➢ The interfering objects (structures on top of the pedestal) and fallen objects around the CRD opening will be removed using a small robot.
➢ Deposits around the CRD opening will be sucked and removed, and the objects fallen inside the deposits will be removed using a small
robot.
➢ The rail for equipment access will be installed inside the pedestal*1.
➢ The objects to be removed (P/F, etc.) will be fastened to the rail to prevent them from tumbling down.
➢ The transportation equipment equipped with a jib will be carried in through the CRD opening, and the objects to be removed will bedisassembled → lifted up → loaded → transferred.
➢ Hereinafter the same procedure will be repeated, and the removal area will be expanded sequentially from around the CRD opening.

•••

The transportation equipment equipped with a jib, required in common for Units 1 to 3 will be designed and manufactured inadvance.
It was decided to first conduct basic tests to verify whether or not it is possible to carry in the equipment through the CRD
opening and to lift up → load → transfer the disassembled pieces, under a test environment simulating Unit 2.
Further, it was decided to conduct basic tests to verify the viability of “the rail for the equipment to access target object” and “fallprevention by fastening with the upper CRD exchanger” required for disassembling and removing the Unit 2 CRD exchanger.

*1) Studies are underway to examine whether the rail for Units 1 and 3 should have a cantilever structure, or the leg portion should
be installed at the bottom of the pedestal. The studies include strength assessment as well.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.226② Disassembly of CRD exchanger◼ Element test items (1/3)： Scope of priorverification by means ofbasic tests

Test items for the unit tests and element tests are selected from the work steps that were studied.
Unit test*1

Work
Unit

Comm
on for1 to 3

Step

Details① Installation of ancillaryequipment outside the pedestal(1/2)② Interference removal outside
the pedestal

Installation of bird's eye camera / lights(Outside the pedestal)Not
required

Utility line installation

Not
requiredCutting/grabbing/moving interfering
objects outside the pedestal

Installation of winch unit

Installation of cable routing equipment③ Installation of ancillaryequipment outside the pedestal(2/2)④ Investigation inside pedestal

2⑤ Installation of ancillaryequipment inside the pedestal⑥ Removal and transfer ofinterfering objects inside thepedestal

Necessity

Not
requiredNot
requiredNot
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 (Establishment 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 Inside the Pedestal).

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

Element test*2
Necessity
Not
requiredNot
requiredNot
requiredNot
requiredNot
required

Not required as this is being implemented as part of the FY2019
Subsidy Project (Establishment 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 Inside the Pedestal).

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

Installation of carrying-in/out rail

Not
requiredInstallation of equipment fortransferring the cut pieces

Not
required

Verification of the status of damage

Not
required

Not required as this must be tested in a simulated environment.

Required

Required in order to verify whether or not it is possible to determine thestatus of damage when sufficient lights and bird's eye cameras are notinstalled.

Installation 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 canbe installed remotely at the designated locations inside the pedestal.

Deployment and extension of thecarrying-in/out rail

Required

Required in order to verify that the conditions enable deployment
and extension.
(Rail specific to Unit 2)

Required

Required in order to verify that the rail can be deployed and extended
without interfering with surrounding structures.
(Rail specific to Unit 2)

Cutting/grabbing/moving pipes andsupportNot
required

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

Not
required

ReasonNot required as this is being implemented as part of the FY2018
Subsidy Project (Interference Removal Outside the Pedestal).

Not
requiredNot
required*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.

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

Not required as this is being implemented as part of the FY2020
Subsidy Project (Interference Removal Inside the Pedestal).

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.227② Disassembly of CRD exchanger◼ Element test items (2/3)： Scope of priorverification by means ofbasic tests

Test items for the unit tests and element tests are selected from the work steps that were studied.
Unit test*1

Work
Unit

Step

Details2⑨ Preparation for removal oflower CRD exchanger(rotating frame)⑩
Removal and transfer of lower
CRD exchanger (rotating
frame)

Carrying-in and installation of cutting
equipment

Necessity

ReasonRequired

Element test*2
Necessity
Required

Required in order to verify that the conditions enable carrying-in and installation.
RequiredCutting of rotating frame

Required

Required in order to verify that the conditions enable cutting.

Required

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 interfering withsurrounding structures (mainly P/F, intermediate work stand).

Moving of the equipment for transferring
cut pieces outside the pedestal

Required

Required in order to verify that the conditions enable moving.

Required

Required in order to verify that the cut pieces can be transferred without interferingwith surrounding structures.

Transfer of cut pieces outside the pedestal(up to the equipment hatch)

Not
required

Carrying-in and installation of cutting
equipment

Required

Lifting up of the cut pieces of the lower
part of CRD exchanger by means of theequipment for transferring cut pieces.

Carrying-in and installation of fall
prevention tool
Moving of the equipment for transferring
cut pieces to the periphery of the CRD
exchanger

Cutting of the upper part of the CRD
exchanger⑧⑫
Upper CRD exchanger
removal and transfer

Required in order to verify that the equipment can be carried in and installed without
interfering with surrounding structures.

Carrying-in and installation of fall
prevention tool

Required

Not required as this is being implemented as part of the FY2018 Subsidy Project(Interference Removal Outside the Pedestal).

Not
required

Required
Required in order to verify that the conditions enable carrying-in and installation.

⑦⑪
Preparation for removal ofupper CRD exchanger

ReasonLifting up of the cut pieces of the upper
part of CRD exchanger by means of theequipment for transferring cut pieces.

Moving of the equipment for transferring
cut pieces outside the pedestal

Transfer of cut pieces outside the pedestal(up to the equipment hatch)

Required

Required in order to verify that cutting is possible by means of the robot and cutting
tools.

Not required as this is being implemented as part of the FY2018 Subsidy Project(Interference Removal Outside the Pedestal).

Required in order to verify that the equipment can be carried in and installed without
interfering with surrounding structures.

Required

Required

Required in order to verify that the conditions enable moving.

Required

Required in order to verify that the equipment can be moved without interfering withsurrounding structures.

Not
required

Not required as this will be verified in ⑩. (Not required as this will be verified forthe lower part of the CRD exchanger (rotating frame), which is thick.)Not
required

Not required as this will be verified in ⑩. (Not required as this will be verified for the
lower part of the CRD exchanger (rotating frame), which is thick.

Required

Required in order to verify that the conditions enable lifting up.

Required

Required in order to verify that the cut pieces can be lifted up without interfering withsurrounding (mainly top) structures.

Not
requiredThis is similar to the work carried out in ⑩. As it will be verified in ⑩, this test is
not required.

RequiredNot
required

Not required as this is being implemented as part of the FY2018 Subsidy Project(Interference Removal Outside the Pedestal).

Not
required*1) Unit test: Test conducted with a stand-alone equipment outside the simulated environment. *2) Element test: Test

Required in order to verify that the cut pieces can be transferred without interferingwith surrounding structures.

Not required as this is being implemented as part of the FY2018 Subsidy Project(Interference Removal Outside the Pedestal).

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.228② Disassembly of CRD exchanger◼ Element test items (3/3)： Scope of priorverification by means ofbasic tests

Test items for the unit tests and element tests are selected from the work steps that were studied.
Unit test*1

Work
Unit
1 and 3step

Details⑤’
Installation of ancillaryequipment inside thepedestal⑥’ Removal and transfer
of interfering objects inside
the pedestal⑦’
Suction of deposits andremoval of fallen objects⑧’
Objects to be removed(Preparation for removal of
P/F, etc.)⑨’
Removal of objects to be
removed (PF, etc.)

Necessity

ReasonElement test*2
Necessity

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 be installed
remotely at the designated locations inside the pedestal.

Deployment and extension of the carryingin/out rail

Required

Required in order to verify that the conditions enable deployment and extension.
(Rail specific to Units 1/3)

Required

Required in order to verify that the rail can be deployed and extended without
interfering with surrounding structures. (Rail specific to Units 1/3)

Cutting/grabbing/moving pipes and support

Not
required

Not required as this is being implemented as part of the FY2020 Subsidy
Project (Interference Removal Inside the Pedestal).

Not
required

Not required as this is being implemented as part of the FY2020 Subsidy Project(Interference Removal Inside 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 canbe 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 canbe 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 ⑧’⑨’. As it will be verified in ⑧’⑨’, thistest is not required.

Carrying-in and installation of cutting
equipment

Required

Required

Required in order to verify that the conditions enable carrying-in and installation.

Required in order to verify that the conditions enable carrying-in and installation.

Carrying-in and installation of fall
prevention tool

RequiredMoving 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 interfering withsurrounding 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 Step 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

Unit tests and element tests that are determined to be required will be conducted.

*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.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.229② Disassembly of CRD exchanger◼ Basic test plan (1/3)

Cut piece C

Cut piece D

An overview of the basic tests is described below.
② Access for the equipment
for transferring the cut pieces⑤ Pulling out the upper
portion of the CRD exchanger, lifting it up,
loading and transferring it

Cut piece B

Cut piece A

4 selected cut pieces① Installation and extensionof the rail for carrying-in/out④ Pulling out the lower portionof the CRD exchanger, lifting it up,
loading and transferring it••③ Fall prevention measures
for the lower CRD exchanger
by means of a toolNo.

Reason for selection of the cut pieces

A

As the cut piece is highly likely to get stuck while it is being pulled out, due to the interfering objects above andbelow it.

B

As work of installing the tool on to the cut piece needs to be carried out in a confined space (intermediate work
stand) by means of a robot.

C

As this is the maximum height and the clearance up to the structures at the top while pulling out and lifting up
the cut piece is the least.

D

As this is the maximum width at the time of loading on the carrier and the clearance up to the CRD opening is
the least.

4 cut pieces (each weighing approx. 100kg) have been narrowed down from the CRD exchanger to be cut. The viability of aseries of operations including pulling out, lifting up, loading and transferring these cut pieces will be verified.
Cutting and making holes for installing the hoisting accessories will be verified during the element tests next year.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.230② Disassembly of CRD exchanger◼ Basic test plan (2/3)

The items to be verified by means of basic tests are indicated below.
No.

Test
classificati
on

Overview of tests

Items to be verified

1

Internal
investigation• With the ancillary equipment inside the pedestal (camera, lights)
installed only in the periphery of the CRD opening, a robot will be
introduced inside the pedestal and will be moved to predetermined
locations on the P/F, the intermediate work stand and at th bottom of
the pedestal.

• It will be verified whether or not the status of damage around the robot
can be investigated using the camera, etc. installed on the robot hand.
• It will be verified whether or not the robot can grab the CRD exchanger,intermediate work stand with its hands and push it back and forth(fixation status).

2

Installationof the rail

• An equipment with the rail mounted on the carrier will be installedinside the pedestal, the rail will be installed at a predetermined
location on the P/F using the equipment, and the rail will be
extended up to the vicinity of the side opposite to the CRD opening.

• It will be verified whether or not the work from carrying-in the rail toinstalling it can be performed without interfering with the structuresinside the pedestal.
• It will be verified whether or not the equipment can travel on theextended rail up to the periphery of the CRD exchanger to be cut.

3

Fallprevention• An equipment with the fall prevention tool loaded on the carrier will
be installed inside the pedestal, and the fall prevention tool will be
installed on the upper CRD exchanger (trolley frame) using theequipment.
• The fall prevention chain attached to the fall prevention tool will befastened to the lower CRD exchanger using a robot.

• It will be verified whether or not the work from carrying-in the fall
prevention tool to installing it can be performed without interfering withthe structures inside the pedestal.
• It will be verified whether or not the robot is able to perform theoperation of fastening the fall prevention chain to the lower CRD
exchanger in a confined space such as the intermediate work stand.
• It will be verified whether or not the fall prevention tool and the fall
prevention chain would hinder the subsequent work of removing the
CRD exchanger.

4

Lower CRD
exchanger
removal• The retaining chain attached to the fall prevention tool will befastened to the lower CRD exchanger using a robot.
• The cut pieces will be pulled out, lifted up, loaded and transferredoutside the pedestal using the equipment while extending theretaining chain with a robot.

• It will be verified whether or not the robot is able to perform theoperation of fastening the retaining chain to the lower CRD exchanger
in a confined space such as the intermediate work stand.
• It will be verified whether or not a 100[kg] cut piece can be pulled out,
lifted up, loaded and transferred outside the pedestal without
interfering with the structures inside the pedestal.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.231② Disassembly of CRD exchanger◼Basic test plan (3/3)
The items to be verified by means of basic tests are indicated below.
No.

Test
classification

Overview of tests

Items to be verified

5

Removal ofupper CRD
exchanger• The cut pieces will be pulled out, lifted up, loaded andtransferred outside the pedestal using the equipment.

• It will be verified whether or not a 100[kg] cut piece can bepulled out, lifted up, loaded and transferred outside the pedestal
without interfering with the structures inside the pedestal.

6

Removal ofrails and tools• The rail and tools used for disassembling and removing
the CRD exchanger will be removed using the equipment,
loaded on to the carrier of the equipment and transferredoutside the pedestal.

• It will be verified whether or not the rail and tools can beremoved following the procedures opposite to those followed for
installation.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.232② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (for basic tests)
The equipment and tools used for the basic tests are indicated below.
No.

Name

1

CRD exchanger
removal robot

Approximate
dimensions[mm]
L1,503×W463
×H575

Approximate
mass
[kg]

Outer appearance (schematic
drawing)(10) Universal joint(9) Flexion axis – 1(8) Torsion
axis(12) Lateralrotating shaft(6) Lateralrotating shaft(7) Holding
shaft(5) Flexion axis – 3(3) Flexion axis – 1(1) Holding shaft

Equipment fortransferring cut
pieces[Dimensions when the jib
is raised with a derrick]
L2,137.2×W528.8
×H1,448[Dimensions when the jib
is lowered]L2,679.2×W528.8
×H966.3

295

Overview•

Approx. 100(11) Flexion axis – 2

2Outer appearance (picture)(4) Flexion axis – 2

Performs the work of transportation andinstallation by holding cutting equipment,
tools, etc. in its arms.
• Moves inside the pedestal by remote
operation of the equipment and verifies
the status using built-in cameras.
• Attaches and releases the hoisting
accessories with its arms.
(Note) This is a product developed as partof the government R&D project from theprevious year. It is not a new product fromthis year.

(2) Torsion axis

•
•
•
•
•
•

Installed on the CRD rail, and travels
inside the pedestal by remote operation.
Lifts objects that are approx. 100 [kg].
Swivels to load on to the carrier.
Moves outside the pedestal by remote
operation
Loads tools on to the carrier.
Upon attaching the hoisting accessory
to the tool, moves to the installation
location.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.233② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (for basic tests)

The equipment and tools used for the basic tests are indicated below.
No.

Name

3

Rail for carryingin/out

Approximate
dimensions[mm][Dimensions whenretracted]
W1,000×B2,000
×H1,500[Dimensions when
spread out]
W1,000×B3,574
×H1,643

Approximate
mass
[kg]
480

Outer appearance (schematic
drawing)Outer appearance (picture)

Overview
•
•
•
•
•
•

Acceptable maximum load 400[kg]Weight reducing spring mechanism when
the rail is spread out
With cable routing guide roller
With guide for preventing the equipmentfrom overturning
With stopper for preventing the main unit
from getting lifted
With carrying-in/out rail folding mechanism

4

Extension rail A

W700×B1,100
×H492

100

•

With guide for preventing the equipmentfrom overturning

5

Extension rail B

W700×B1,050
×H462

100

•

With guide for preventing the equipmentfrom overturning

6

Extension rail C

W605×B835
×H285

35

•

Corner part of extension rail

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.234② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (for basic tests)

The equipment and tools used for the basic tests are indicated below.
Approximate
dimensions
[mm]

No.

Name

7

Fall prevention
and anti-rotation
tool

W807×B231
×H522

Fall prevention
partitioning tool

W807×B181.7
×H639

8

Approximate
mass
[kg]
11.3

Outer appearance (schematic
drawing)Outer appearance (picture)

Overview
•
•
•

13.3

•
•
•

9

Hoisting jig(Projection lock
type A)

W135×B201
×H217

3.3

•
•
•
•
•

With rotating frame stopper and tool offset
prevention mechanism
Prevention of overturning of trolley frame
Rotating frame fall prevention chain

With rotating frame stopper and tool offset
prevention mechanism
Prevention of overturning of trolley frame
Rotating frame fall prevention chain, cut pieceretaining chain

Inserted into the φ25 hole made by a separate
tool, and is held in place.
Furnished with a suspension length adjustment
tool, and hook for the equipment for transferring
cut pieces
Target thickness: Maximum 40 [mm]Removal by remote operation using a robot
Offset from the cutting line

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.235② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (for basic tests)

The equipment and tools used for the basic tests are indicated below.
No.

Name

10

Hoisting jig(Projection lock
type B)

Approximate
dimensions[mm]

Approximat
e mass[kg]

W166×B100
×H201

3.3

Outer appearance (schematic
drawing)Outer appearance (picture)

Overview
•
•
•
•

11

Hoisting jig(Use and throw
type (leafspring))

W212×B108
×H60

1.3

•
•
•

12

Hoisting jig(Use and throwtype(projection))

W212×B108
×H60

1.3

•
•
•

Inserted into the φ25 hole made by aseparate tool, and is held in place.
Furnished with a suspension length
adjustment tool, and hook for theequipment for transferring cut pieces
Target thickness: Maximum 40 [mm]Removal by remote operation using arobot

Inserted into the φ25 hole made by aseparate tool, and is held in place.
For fall prevention, for hoisting the cut
piecesTarget thickness: Maximum 40 [mm]Inserted into the φ25 hole made by aseparate tool, and is held in place.
For fall prevention, for hoisting the cut
piecesTarget thickness: Maximum 40 [mm]©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.236② Disassembly of CRD exchanger◼ Designing and test manufacturing of the disassembly and removal equipment (for basic tests)

The equipment and tools used for the basic tests are indicated below.
Approximate
dimensions[mm]

Approximat
e mass[kg]

Outer appearance(schematic drawing)

No.

Name

Outer appearance (picture)

Overview

13

Suspension
lengthadjustment tool

W87.2
×B88
×H558.5

3.4

•
•
•

14

2 point
suspension tool

W377.5
×B51.4×H251.5

1.5

•
•

15

Mini
hook

W50
×B15
×H150

0.45

•

Acceptable maximum load: 150[kg]Lifting height: 2,500 [mm]Breakdown of the weight:(1) Chain pulley block 2.4[kg]× 1(2) Mini hook 0.45[kg]× 2(2) Shackle 0.04[kg]× 2• Usage:(1) Carrying-in/out rail deploying portion(2) Fall prevention of the lower part of CRD
exchanger(3) Cut piece retainer
Acceptable maximum load: 150[kg]Breakdown of the weight:(1) Jump ring 0.32[kg]× 1(2) Mini hook 0.45[kg]× 2(2) Double shackle 0.16[kg]× 2• Usage:(1) Hoisting of cut pieces(2) Cut piece retainer(Mounted on equipment for transferring cut pieces
and the suspension length adjustment tool)
Acceptable maximum load: 150[kg] (Safety
factor: 4.6)
• Usage:(1) Carrying-in/out rail deploying portion(2) Fall prevention of the lower part of CRD
exchanger(3) Cut piece retainer(Mounted on equipment for transferring cut pieces
and the suspension length adjustment tool)©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.237② Disassembly of CRD exchanger◼Designing and test manufacturing of the simulated bodyPedestal innerwall surface

Rotating
equipment
housing

Rotating frame
Structures at
the top

P/F
Trolleyframe

Equipment fortransferring cut pieces
Winch
Simulated CRD
exchanger
CRD rail

Opening at
the center

Simulated CRD exchanger (upper part)

Rail forcarrying-in/out

Intermediate
work stand
P/FIntermediate
work stand

Robot for exchanger
removalPedestalbottomCamera &lightsFacility for mock-up test of the inside of the Unit 2 pedestal (Illustration of overall view)Rotating
frame
Simulated CRD exchanger (lower part)

Basic test was conducted using the facility simulating the inside of Unit 2 pedestal and the simulated CRD exchanger.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.238② Disassembly of CRD exchanger◼ Installation location of the bird's eye cameras and lights (1/2)
180°

Camera ①[Installation height：1000mm above the P/F]

Camera for internal
investigation

Simulated CRD
exchanger

Camera specifications
Φ32 CMOS+LED lights

Camera specificationsCANON VB-M44

270°

90°

Camera ③[Installation height：1200mm above the P/F]

Camera ②[Installation height：600mm above the P/F]

P/F

Camera specifications
Φ55 CMOS +40W LED lights

Rail forcarryingin/out

0°

Camera specificationsCANON VB-M44

Camera installation location (Floor plan on the P/F)
Basic test was conducted by installing bird's eye cameras and lights on the P/F in the facility simulating the inside of Unit 2 pedestal.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.239② Disassembly of CRD exchanger◼ Installation location of the bird's eye cameras and lights (2/2)
Camera ④[Installation height：1000mm above the pedestal bottom]

Camera ⑤[Installation height：1800mm above thepedestal bottom]

180°

PedestalbottomRotating
frame

Camera specificationsCANON VB-M44

Camera specifications
Panasonic WV-S6110

270°

90°

Camera ⑥[Installation height：1500mm above thepedestal bottom]

Camera ⑦[Installation height：1900mm above thepedestal bottom(Above the intermediate work stand)]Intermediate
work standCamera specifications
Panasonic WV-S6110

0°

Camera specifications
Panasonic WV-S6110

Camera installation location (Floor plan from the intermediate work stand to the pedestal bottom)
Basic test was conducted by installing bird's eye cameras and lights on the intermediate work stand and pedestal bottom in the facility simulating the insideof Unit 2 pedestal.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]② Disassembly of CRD exchanger

No.240①： Front camera②： Right hand camera③： Left hand camera[Camera specifications: For vehicular installation]◼ Installation location of the equipment cameras (1/2)

③

①
②

①

Robot for CRD exchanger removal (in the vicinity of the CRD rail)③②
Camera image (Monochrome setting during the test)

Basic test was conducted by installing cameras on the CRD exchanger removal robot.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.241② Disassembly of CRD exchanger◼Installation location of the equipment cameras (2/2)②①： Front camera②： Camera at the tip of the jib③： Rear camera[Camera specifications: For vehicular installation]③①②

Equipment for transferring cut pieces (on the CRD rail)①③
Camera image (Monochrome setting during the test)

Basic test was conducted by installing cameras on the equipment for transferring cut pieces.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.242② Disassembly of CRD exchanger◼ Basic test results (1/10) [Internal investigation [1/2]]
Robot for exchanger removal

Lowering

Equipment fortransferring cut pieces

Lowering

Equipment fortransferring cut pieces

P/F

Movement*1
Movement*1

Intermediate work stand

Robot forexchanger
removalRobot for exchanger
removalMovement*1

A robot was introduced with the ancillary equipment (bird's eye cameras and lights) inside the pedestal installed only in the periphery of the CRD opening.
*1) The robot used in the basic test was developed during the government R&D project last year. It can catch hold of a beam, etc. and walk but there are issues in its movement
on level ground.
During the basic test the robot was moved manually. In this government R&D project, a robot with enhanced moving performance is planned to be developed,©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.243② Disassembly of CRD exchanger◼ Basic test results (2/10) [Internal investigation [2/2]]

Confirming the status of damage of the structures at the top

Confirming the status of damage of the intermediate work standConfirming the status of damage with the pressing force of the arm

Confirming the status of damage at the pedestal bottom

The test results showed that it could be verified the status of damage of the P/F and the intermediate work stand, as well as the status of damage of the CRD exchanger.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.244② Disassembly of CRD exchanger◼ Basic test results (3/10) [Installation of the rail]
Extension rail
Equipment for transferring cut pieces
Robot for exchanger
removalCarrying-in and lifting

Rotation

Delivery of the winch and entryof the equipment fortransferring cut
pieces inside the pedestal byremote operation
Installation of theextension rail of the carrier
on to the P/F, withpositioning assisted by a
robot

Installation

The test results showed that it would be possible to enable the equipment to access cut pieces located farthest from the CRD opening, by installing the rail on the
P/F and extending it.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.245② Disassembly of CRD exchanger◼ Basic test results (4/10) [Fall prevention [1/2]]
Equipment for transferring cut pieces
Fall prevention
tool B① Toolinstallation

Fall prevention
tool A

Fall prevention tool A installation② Fixing by operating the fixing lever bymeans of the robot for exchanger removal
Robot for exchanger
removalFixing lever
Fall prevention tool B installation
It was verified that the fall prevention jig can be installed on the trolley to fix it by a robot operating a jig.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.246② Disassembly of CRD exchanger◼ Basic test results (5/10) [Fall prevention [2/2]]
Fall prevention tool A

Fall prevention tool B

Chain pulley blocks

A

Installation of hoisting accessories for fall prevention
A

Hoisting accessory(For fall prevention)

Hoisting accessory(For holding in place)[A-A cross-section]① Installing the hoisting accessories
on the rotating frame by means of therobot for exchanger removal

Illustration when installing hoisting accessories

The test results showed that it would be possible to fasten the upper CRD exchanger (trolley frame) and the lower CRD exchanger (rotating frame) byconnecting the hoisting accessory with the chain pulley block hanging from the fall prevention tool to the rotating frame by using a robot.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.247② Disassembly of CRD exchanger◼ Basic test results (6/10) [Lower CRD exchanger removal [1/2]]
Equipment for transferring
cut pieces② Removing theretaining tool by meansof the robot for
exchanger removal

Retaining tool
Start of pulling out the cut piece

Cut piece of the lower
CRD exchanger① The cut piece is pulled out bymeans of the slewing movementof the jib of the equipment fortransferring cut pieces.

Robot for exchanger removal

While pulling out the cut piece

The cut piece can be prevented from colliding with the structures in the periphery while it is being pulled out by means of the retaining jig.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.248② Disassembly of CRD exchanger◼ Basic test results (7/10) [Lower CRD exchanger removal [2/2]]④ Transfer③ LoadingEquipment for transferring cut pieces② Lifting

Lifting

Cut piece of the lower CRD exchanger① Pulling out

Robot for exchanger removal

Loading

Transfer

The test results showed that it would be possible to pull out, lift up, load and transfer the lower CRD exchanger (rotating frame) cut piece.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.249② Disassembly of CRD exchanger◼ Basic test results (8/10) [Upper CRD exchanger removal [1/2]]② Transfer

Equipment for transferring cut pieces
Robot forexchanger removal① Pulling out, lifting up, loading

Cut piece of the upper CRD
exchanger

Start of pulling out

Hoisting jig

Loading

Transfer

The test results showed that it would be possible to pull out, lift up, load and transfer cut pieces located in areas with extremely tight clearance up to the upperinterfering objects (CRD support).
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.250② Disassembly of CRD exchanger◼ Basic test results (9/10) [Upper CRD exchanger removal [2/2]]
Equipment for transferring cut pieces① Pulling out, lifting up, loading② Transfer

Cut piece of the upper CRD exchanger

Lifting

Robot for exchanger
removalLoading

Transfer

The test results showed that it would be possible to pull out, lift up, load and transfer cut pieces located farthest from the CRD
opening.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.251② Disassembly of CRD exchanger◼ Basic test results (10/10) [Summary of basic test results]
Results of the basic tests are summarized below.
No.

Test
classificationTest results

1

Internal
investigation• It was projected that it will be possible to verify the status of damage of the P/F and the intermediate work stand, as well as the status of damage of the
CRD exchanger, with the help of the images captured by the camera and the push operation of the robot.

2

Installation of
the rail• It was verified that the work from carrying-in the rail to installing it can be performed without interfering with the structures inside the pedestal.
• It was verified that the equipment can travel on the extended rail up to the periphery of the CRD exchanger to be cut.

3

Fallprevention• It was verified that the work from carrying-in the fall prevention tool to installing it can be performed without interfering with the structures inside thepedestal.
• It was verified that the fall prevention chain can be fastened to the lower CRD exchanger by means of a robot in a confined space such as the intermediate
work stand.

4

Lower CRD
exchanger
removal• It was verified that the retaining chain can be fastened to the lower CRD exchanger by means of a robot in a confined space such as the intermediate work
stand.
• It was verified that cutting tool can be positioned without interfering with the structures inside the pedestal.
• It was verified that a 100[kg] cut piece can be pulled out, lifted up, loaded and transferred outside the pedestal without interfering with the structures inside
the pedestal.

5

Removal ofupper CRD
exchanger• It was verified that cutting tool can be positioned without interfering with the structures inside the pedestal.
• It was verified that a 100[kg] cut piece can be pulled out, lifted up, loaded and transferred outside the pedestal without interfering with the structures inside
the pedestal.

6

Removal ofrail and tools• It was verified that the rail and tools can be removed following the procedures opposite to those followed for installation.

The basic test was conducted in a simulated Unit 2 environment. The test results showed that it will be possible to carry-in the equipment
through the CRD opening, and lift up, load and transfer the cut pieces.
Studies on the method for disassembly and removal for Units 1 and 3 will be continued based on the results of the basic tests.
©International Research Institute for Nuclear DecommissioningNo.252

6. Implementation items of this project [1) (2) Development of disassembly and removal technology]② Disassembly of CRD exchanger: Planned◼ Development process: Planned (after revision)*: Actual
FY2021

FY2022

Study items
4

Major milestones

5

6

7

8

9

10

11

Interim
Report
▼

12

1

2

3

4

5

6

7

8

Interim
Report▼9

10Interim
Report
▼

11

12

1

2

Final
report
▼1. Conceptual study

2. Element test planning
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 element tests.

3©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.253② Disassembly of CRD exchanger: Summary➢ The preconditions pertaining to disassembling the CRD exchanger were compiled.
➢ Technologies that must be developed in common for Units 1 to 3 were identified upon studying
the method of disassembly and removal of CRD exchangers in Units 1/3 and the work steps
involved.
➢ Basic tests were conducted to verify the viability of carrying-in the equipment through the CRD
opening and lifting up → loading → transferring the disassembled pieces, under a test
environment simulating Unit 2, and prospects of actual equipment applicability were seen.
➢ In the future, work steps specific to each unit will be studied in detail, the equipment fordisassembly and removal will be designed and test manufactured, an element test plan will be
drafted, and the feasibility of the method of disassembly and removal of CRD exchanger will beverifid through element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.254

Solicitation items are listed.

③ Interference removal from pump pit
A submersible pump needs to be installed in the pump pit inside the PCV as one of the methods forcirculating water inside the PCV while increasing the scale of retrieval of fuel debris and reactor
internal structures. Element tests have been conducted based on development carried out in the pastand it has been projected that the pump can be suspended, lowered and installed (fixed) inside thepit, 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 captured by thecamera, and then cutting, etc. and transferring will be studied in detail, and its 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.255③ Interference 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”)

L門型揚重機type gantry craneLowering

ロボット
Robot
アーム
arm

Pump
ポンプ
Lowering

Hose
ホース

Pump pit

ポンプ吊り降ろし
Pump suspension

Stand
for
配管設置
用スタンド
installing
pipingD/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 havealready been removed. The method for removing interfering objects from inside the pump pit, which is a pre-condition, will be
specified and feasibility will be verified by element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.256③ Interference removal from pump pit
Coolingequipment[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.
Installation of[Implementation details]•
Actual equipment information, results of the analyses andinvestigations carried out so far on the status of interfering objects inthe periphery of the pump pit for each unit are consolidated, and thepreconditions 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 the basement floor isstudied.
•
The remote controlled equipment, cutting equipment required for
implementing the removal method considered, are studied.
•
Element tests are planned and implemented to verify the feasibility of
the considered technology for removing interfering objects from inside
the pump pit.

Insoluble
nuclideremovalsystemsubmersible
pump in thepump pit[Expected outcome]•
Presentation of the method of removing interfering objects such as existing
pump, etc. from inside the pump pit

Soluble nuclide
removal system(New/existing)Illustration after making theD/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.257③ Interference removal from pump pit[FY2021 Implementation Details]◼ Compilation of information on the actual sitea. Compilation of the locations of the pump pit➢ The locations of the pump pits installed in Units 1 to 3 were identified.
b. Consolidation of the status of fuel debris investigation➢ The status of fuel debris on the basement floor of the PCV in Units 1 to 3 was consolidated.
◼ Compilation of preconditions
a. Consolidation of the status in the pump pits and above them, and scope of removal of the existing pumps➢ The status of inflow of fuel debris in the pump pit and above it was consolidated, and the scope of removal of existing pumps
depending on that status was studied.
b. Consolidation of the specifications for the equipment and floor sump pumps, and the pump pits
➢ Specifications of the existing equipment and floor sump pumps, as well as the pump pits was consolidated.
c. Selection of target pump pit location➢ The pump pit from which interfering objects will be removed and in which a new pump will be installed was selected.
d. Summary of preconditions➢ The preconditions pertaining to the studies conducted during this subsidy project were consolidated.
◼ 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.
b. Illustrations of the work
➢ Illustrations of the work mentioned in a. above were studied.
◼ Selection of element test items
a. Selection of test items for the unit tests and element tests➢ The test items for the unit tests and element tests to be conducted during this subsidy project were selected.
◼ Study of equipment used
a. Study of hoisting equipment➢ The hoisting equipment used for lifting up the existing pump from the pump pit was studied.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.258③ Interference removal from pump pit◼ Compilation of information on the actual site a. Compilation of the locations of the pump pits
➢ Locations of the pump pits inside the PCV in Unit 1 and in Units 2, 3 are indicated below.
As the locations in Units 2 and 3 are the same, they are listed together, (Same applies in the following pages
as well.)
Jet deflector

90°
Inside thepedestal

Inside thepedestal

Work floor90°

Jet deflector
PLR pump
A system

Equipment hatch

X-6 penetration

45°
Pump pits inside
PCVWork floor

160°
PLR pump
A system

0°

Personnel
air lock

Personnel
air lock

180°

0°
180°

Pump pits inside
PCV
Connecting
pipes

202.5°
Work floor

225°
Inside thepedestal
Pump pit

270°

X-6 penetration

Layout drawing of PCV basement first floor in Unit 1
Locations of the pump pits inside PCV in Unit 1: At the outer wall surface of the pedestal in the vicinity of 45°on the
PCV basement first floor: At the outer wall surface of the pedestal in the vicinity of 225°on
the PCV basement first floor

Inside thepedestal
Pump pit

PLR pump
B system
Equipment hatch

270°

Connecting
pipes*: Drawn based on thedrawings of Unit 4

Layout drawing of PCV basement first floor in Units 2, 3*
Locations of the pump pits inside PCV in Unit 2, 3
: At the outer wall surface of the pedestal in the vicinity of 160°on the PCV basement first floor: At the outer wall surface of the pedestal in the vicinity of 180°on the PCV basement first floor
At the outer wall surface of the pedestal in the vicinity of 202.5°on the PCV basement first floor©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.259③ Interference removal from pump pit◼ Compilation of information on the actual site b. Consolidation of the status of fuel debris investigation➢ The status of fuel debris on the basement floor of the PCV in Units 1 to 3 is given below.
It is assumed that there are deposits on the fuel debris in all of Units 1 to 3. It has not been determined whether or not the deposits
outside the pedestal should be handled as fuel debris, but in this subsidy project the deposits have been handled as fuel debris similar
to the approach adopted for deposits inside the pedestal.
Unit 1
Pump pit inside PCV(45°)

Unit 2

Unit 3

Pump pit inside pedestal
Connecting
pipes

Connecting
pipes

Illustration
showing the
expanse offuel debris on
the PCVbasement
floor
Pump pit inside pedestal
Pump pit inside pedestal

Connecting pipes
Pump pit inside PCV (225°)

Spread of fuel debris： Approx.
110°(estimated)

Status ofinvestigationand estimation

・The fuel debris is likely to have spread up to
the D/W floor through the pedestal opening.

Spread of fuel debris：
Unknown

Pump pits inside
PCV

Pump pits inside PCV

Spread of fuel debris：
Unknown

・It is assumed that the fuel debris has spreadoutside the pedestal through the pedestal
opening, but has not led to a shell attack (hasnot reached the containment vessel).

・Unknown.

＊1＊1: Cited from “Subsidy Project of Decommissioning and Contaminated Water Management in the
FY2017 Supplementary Budget” - Upgrading of the Comprehensive Identification of Conditions
inside Reactor.

The fuel debris in the pump pits inside the PCV in Units 1 to 3 other than the pump pits (160°) inside PCV in Units 2, 3, is likely to have passed
through the connecting pipes from the pump pits inside the pedestal and entered into the pump pits inside the PCV.
Fuel debris is likely to have deposited above the pump pit (225°) inside PCV in Unit 1.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.260③ Interference removal from pump pit◼ Compilation of preconditions a. Consolidation of the status in the pump pits and above them, and scope of removal of the existing pumps
The condition of the pump pits assuming inflow of fuel debris in the pump pits and above them, and the scope of removal of existing pumps depending on that wasstudied.
The results of the study are given below.
Case no.
Unit
assumedExisting
pump

Case 1*Case 2

Case 3*

Case 4

Units 1 - 3

Units 1 - 3

Unit 2, 3

Unit 2, 3

D/W water level

Scope ofremovalD/W water level

D/W water level
Fuel debris

Scope ofremovalD/W waterlevel*: For Case 1/Case 3[Proposal for
consideration]① Installation of
intake pump outside
the pump pit (at thebase of D/W)
Illustration

Cutting
location

Pump pit

Fuel debris

Pump pit

Fuel debris

Pump pit

Pump pit

Status offuel debris

Fuel debris present above the pumppits / inside the pump pits

Fuel debris present in some part
inside the pump pits

Fuel debris present above the pumppits

Fuel debris absent above the pumppits / inside the pump pits

Scope ofremoval ofexistingpump―

Removal of existing pump in parts―

Removal of entire existing pump(removal in its entirety)↓② Establishment ofwater circulation
system
↓③ Fuel debris
retrieval+Removal of existingpump

In the method considered at present, it is assumed that fuel debris will be retrieved (processed) after the water circulation system isestablished.
Hence, Case 2 and Case 4, in which securing space to install a new pump inside the pump pit without retrieving fuel debris seems possible,
were studied.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.261③ Interference removal from pump pit◼ Compilation of preconditions b. Consolidation of the specifications for the equipment and floor sump pumps and thepump pits➢ The specifications for the equipment and floor sump pumps, as well as the pump pits in Units 1 - 3 were consolidated.
The results of consolidation are given below.
FigureUnit 1

Pump specifications(Manufactured: Kansui Pump Co., Ltd)
Equipment sump pump /Floor sump pumpSame modelＨ

Ｈ: 2,112[mm]Φ: 305[mm]
Mass: 293 [kg]Number of pumps:
Equipment sump pumps: 2
Floor sump pumps: 2(2 pumps installed in a pit)

Unit 2

Unit 3Equipment sump pump /Floor sump pumpSame model

Equipment sump pump /Floor sump pumpSame model

Ｈ: 2,247[mm]
Φ: 305[mm]
Mass: Unknown
Number of pumps:
Equipment sump pumps: 2
Floor sump pumps: 2
Oil sump: 2(2 pumps installed in a pit)

Ｈ: 2,235[mm]Φ: 305[mm]
Mass: Unknown
Number of pumps:
Equipment sump pumps: 2
Floor sump pumps: 2
Oil sump: 2(2 pumps installed in a pit)

W: 1,250[mm]D: 700[mm]
H: 1,230[mm]

W: 1,250[mm]D: 700[mm]
H: 1,230[mm]160° Oil pit
180° Floor pump pit
202.5° Equipment pump pit
Same dimensions

160° Oil pit
180° Floor pump pit
202.5° Equipment pump pit
Same dimensions

ΦPump pit specifications(Outside the pedestal)

D

H

W

W: 1,400[mm]D: 700[mm]
H: 1,230[mm]
45° Floor pump pit
225° Equipment pump pit
Same dimensions

It was decided that during this subsidy project, studies would be conducted using the following values for the height and mass of theequipment and floor sump pumps, and the specifications of the pump pit.
Height of the equipment and floor sump pumps: 2,247 [mm] (Unit 2) ⇒ As it is the highest.
Mass: 320[kg] (Unit 2 assumed＊) ⇒ As it is the heaviest. Diameter： Φ305[mm] (Same for all units).
Specifications of the pump pit： 1,250(W)×700(D)×1,230(H)[mm] (Units 2, 3) ⇒ As it is the most confined.

*: As the mass of the sump pumps inUnits 2, 3 was unknown, it wascalculated by means of ratio
calculation using the specifications of
the Unit 1 pump and the Unit 2 pumpwhich has the most H.
Assumed as 2,112：293=2,247：xｘ=312kg=320kg (rounded up to thenearest whole number).

[Reference: Unit 4 sump pumpspecifications]
H: 2,187[mm]
Mass: 3,05[kg]©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.262③ Interference removal from pump pit◼ Compilation of preconditions c. Selection of target pump pit location (1/5)➢ In order to select the target pump pit, the interfering objects on the grating near the top of the pump pit inside PCV on the first floor of the PCV,and the interfering objects on the route used for lifting up the pump were consolidated for the pump pits (45°, 225°) inside the PCV in Unit 1
and the pump pit (202.5°) inside the PCV in Units 2, 3, and a comparative study of the level of difficulty of the work was conducted.
Note that the interfering objects on the access route from the equipment hatch up to the top of the pump pit on PCV first floor were assumed tohave been already removed.
In the case of the pump pits (160°,180°) inside PCV in Units 2 ,3, as the work area is small the PLR piping within close proximity is likely to
get damaged.
Following is a layout drawing of the pump pits (160°,180°) inside PCV in Unit 2, 3.
As it is difficult to perform the work without damaging the surrounding PLR piping,it was decided to study pump pit (202.5°) inside PCV for Units 2, 3.

PLR pipes (System
B)

Pump pits inside
PCV

PLR pipes(System B)

160°
180°
D 202.5°

Grating

PLR piping
supportD

Pump pits inside
PCV(160°,180°)

MS pipes (10B)

D-D View
Floor plan of first floor in Unit 2* （180°: D-D）*: Drawn based on the drawings of Unit 4.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.263③ Interference removal from pump pit◼ Compilation of preconditions c. Selection of target pump pit location (2/5)➢ The interfering objects on the grating near the top of the pump pit inside PCV on the first floor of the PCV, and theinterfering objects on the route used for lifting up the pump for the pump pit (45°) inside the PCV in Unit 1 are given
below.
Lifting
PCV first floor grating

HVH- D (Planned
to be removed.)

Although it is not shown in thisfigure, it is assumed that there
are several pipes and supports
between the pump pit inside
PCV on the PCV first floor andon the PCV basement floor.
(Planned to be removed.)

Concrete
Brackets

Pump

Pipes and supports(Planned to be
removed.)Installation of pump pit (45°) inside
PCV on the basement floor
Pump pit inside PCV(45°)

Layout drawing of Unit 1 PCV first floor
Unit

Unit 1

Installation location

45°

Interfering objects on PCV first floor

・HVH- D (Planned to be removed)

Interfering objects on the lifting route･Concrete brackets･Pipes and supports (Planned to be
removed)Layout drawing of Unit 1 PCV basement floor
As there are concrete brackets right on top of the interfering object, it isdifficult to lift up directly above.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.264③ Interference removal from pump pit◼ Compilation of preconditions c. Selection of target pump pit location (3/5)➢ The interfering objects on the grating near the top of the pump pit inside PCV on the first floor of the PCV, and the interfering
objects on the route used for lifting up the pump for the pump pit (225°) inside the PCV in Unit 1 are given below.
Lifting
Installation of pump pit (225°) inside
PCV on the basement floor

MS pipe rack

PCV first floor grating

Although it is not shown in this figure,it is assumed that there are several
pipes and supports between the pump
pit inside PCV on the PCV first floor
and on the PCV basement floor.
(Planned to be removed.)

Concrete
Brackets

Pump

Shield(Planned
to beremoved)HVH-A (Planned
to be removed)
Pump pit inside PCV(225°)

270°
Unit

Layout drawing of Unit 1
PCV firstUnit
floor
1

Installation location

225°

Interfering objects on PCV firstfloor

・MS pipe rack
・HVH-A (Planned to be removed)
・Shield (Planned to be removed)

Interfering objects on the lifting
route･Concrete brackets･Pipes and supports (Planned to be
removed)・Shield (Planned to be removed)

Shield (Planned to be removed)
Pipes and supports (Planned tobe removed)

Layout drawing of Unit 1 PCV basement floor
As there are concrete brackets right on top of the interfering object, it isdifficult to lift up directly above.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.265③ Interference removal from pump pit◼ Compilation of preconditions c. Selection of target pump pit location (4/5)➢ The interfering objects on the grating near the top of the pump pit inside PCV on the first floor of the PCV, and theinterfering objects on the route used for lifting up the pump for the pump pit (202.5°) inside the PCV in Units 2, 3 aregiven below.
Lifting
PCV first floor grating

Installation of pump pit (202.5°)
inside PCV on the basement floor
Pump

Although it is not shown in thisfigure, it is assumed that there areseveral pipes and supports
between the pump pit inside PCV
on the PCV first floor and on the
PCV basement floor.
(Planned to be removed.)

MS pipes

Layout drawing of Unit
2.3 PCV basement floor

HVH-A (Planned
to be removed)

Pump pit inside PCV(202.5°)

Layout drawing of Units 2, 3 PCV first floor
Unit

Units 2, 3

Installation location

202.5°

Interfering objects on PCV firstfloor･ MS pipes
・HVH-A (Planned to be removed)

Interfering objects on the lifting
route･Pipes and supports (Planned to be
removed)Pipes and supports(Planned to be removed)

Layout drawing of Units2, 3 PCV basement floor©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]③ Interference removal from pump pit

No.266◼ Compilation of preconditions c. Selection of target pump pit location (5/5)➢ The interfering objects on the grating near the top of the pump pit inside PCV on the first floor of the PCV, and the interfering
objects on the route used for lifting up the pump for the pump pits (45°, 225°) inside the PCV in Unit 1 and the pump pit (202.5°)
inside the PCV in Units 2, 3, which were studied in the previous section, were consolidated and the level of difficulty of the work wasevaluated.
The results of evaluation are given below.
[Legend]
Difficult

Unit

Unit 1

Installation location

45°

225°

202.5°

Interfering objects

・HVH- D (Planned to be removed)

・MS pipe rack
・HVH-A (Planned to be removed)
・Shield (Planned to be removed)･ MS pipes
・HVH-A (Planned to be removed)

Evaluation

・ It was determined that space that would
enable installation of the hoisting equipmenton the first floor of PCV can be secured.

・ It would be difficult to secure space thatwould enable installation of the hoisting
equipment because of the MS pipe rack on
the first floor of PCV. Hence the location for
installing the hoisting equipment needs to bestudied.

・ It would be difficult to secure space thatwould enable installation of the hoisting
equipment because of the MS pipes on thefirst floor of PCV. Hence the location for
installing the hoisting equipment needs to bestudied.

Low

High

High

PCV first
floor

Difficulty level*

On the lifting
route

Comprehen
siveevaluation

Units 2, 3Interfering objects･Concrete brackets･Pipes and supports (Planned to be removed)･Concrete brackets･Pipes and supports (Planned to be
removed)・Shield (Planned to be removed)･Pipes and supports (Planned to be
removed)Evaluation

・ There are concrete brackets on the liftingroute due to which the pump cannot be lifted
directly up and removed. Hence the lifting
method needs to be studied.

・ There are concrete brackets on the liftingroute due to which the pump cannot be lifted
directly up and removed. Hence the lifting
method needs to be studied.

・There are no interfering objects on thelifting route and hence it was determinedthat the pump can be lifted directly up.

Difficulty level*

High

High

Low

Difficulty level*

MediumHigh

MediumEasy*： Difficulty level(High→ Medium→ Low)

It was decided that the pump pits (202.5°) inside PCV in Units 2, 3 would be studied based on the study of applicability topump pit (225°) inside PCV in Unit 1, for which the level of difficulty was rated “High” in the comprehensive evaluation.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.267③ Interference removal from pump pit◼ Compilation of preconditions d. Summary of preconditions➢ The preconditions pertaining to the studies conducted during this subsidy project were consolidated. The
results of consolidation 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 to 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

Unit 2 assumed (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)×700(D)×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 ones in which performing work would be
difficult were 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 difficult 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.268③ Interference 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.
[Preconditions]• 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.
*: Case 2
Fuel debris is present in somepart inside the pump pits

<Overview of work steps> Same for Unit 1, Unit 2, Unit 3①

Installation of ancillaryequipment for cutting an
opening in the grating②

Removal of grating③

Removal of interfering
objects under thegrating⑥

Investigation ofdeposits/fuel debris
around the pump pit⑩

Investigation ofdeposits/fuel debris in
the pump pit⑪

Cutting of the pump
(Only Case 2＊)⑭

Cutting/removal of thebolts used for installing
the pump pit cover⑮

Installation of D/Wwater intake pump⑦

Building of dikes
around the pump pit④

Removal of interfering
objects present above
the pump pit⑤

Removal of interfering
objects present
around the pump pit

Measures for
ensuring visibility
inside the pump pit⑨

Cutting an opening in
the pump pit cover⑫

Cutting of the bolts
used for installing thepump⑬

Lifting up the pump⑯

Dike removal⑰

Transfer of interfering
objects⑧©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.269③ Interference removal from pump pit◼ Study of work steps b. Illustrations of the work (1/3)
Illustrations of the removal of existing pump from pump pit (225°) inside PCV in Unit 1 are shown below.
①

Installation of ancillary equipment for cutting an
opening in the grating➁

Portable hoisting equipment

Cutting equipment③

Removal of grating

Removal of interfering objects under the grating

Cutting/removalof grating
Cutting/removal ofdikes, pipes, etc.

ShieldShieldFloor plan

Portion of the grating planned to be cut
Above the PCV first floor grating④

Removal of interfering objects present above the pumppit⑤

Removal of interfering objects present around thepump pit⑥

Investigation of deposits/fuel debris around the pumppit

Camera forinvestigation

Lights

Deposits/fueldebrisCutting/removalof pipes, etc.

ShieldStatus around the pump
pit is unknown

ShieldCutting/removal ofshields, pipes, etc.

©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.270③ Interference removal from pump pit◼ Study of work steps b. Illustrations of the work (2/3)*: Case 2
Illustrations of the removal of existing pump from pump pit (225°) inside PCV in Unit 1 are shown below. Fuel debris is present in somepart inside the pump pits⑦⑧

Building of dikes around the pump pit

Measures for ensuring visibility inside the pump pit⑨

Cutting an opening in the pump pit coverCuttingequipment

Filtered water supply hose
Sludge pump (insidethe dike)
Dike

Pump pit cover(Pipes around the pump pit have been removed)⑩

Investigation of deposits/fuel debris in the pump pit

Dike⑪

Drainage of muddy water(outside the dike)

Floor plan⑫

Cutting of the pump (Only Case 2*)

Cutting of the bolts used for installing the pumpCuttingequipment

Cuttingequipment

LightsCamera forinvestigation

Bolts used for
installing the pumpConfirming
the status
inside thepump pit

Cutting
position

Fuel debris(Pipes around the pump pit have been removed)©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.271③ Interference removal from pump pit◼ Study of work steps b. Illustrations of the work (3/3)
Illustrations of the removal of existing pump from pump pit (225°) inside PCV in Unit 1 are shown below.
⑬⑭

Lifting up the pumpConcretebrackets

Lifting

Cutting of the bolts used for installing the pump
pit cover

D/W water intake pipe

Layoutdrawing

Basement
floor hose

Wire feed

Bolts used for
installing thepump pit cover
Grating opening
space

⑯

Portable hoisting
equipment

Cuttingequipment

D/W water intake pump
Pump specifications
Dimensions:Φ280×H750［㎜］
Mass： 80［㎏］
Diameter： 50［ A］

Lateralview⑰

Dike removal

Installation of D/W water intake pump
Coupler

Pump pitcover

PCV first
floor grating⑮

Transfer of interfering objects
Equipment hatch

Transfer
equipment

Dike©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.272③ Interference removal from pump pit◼ Selection of element test items a. Selection of test items for the unit tests and element tests (1/2)➢ Test items for the unit tests and element tests were selected from the work steps that were studied.
The test items selected and the reason for selection are given below.
Unit test: Test conducted with a stand-alone equipment outside the simulated environment.
Element test: Test conducted by combining all equipment in a simulated environment.
Work

Unit test

Step

Details① Installation of ancillary equipment for
cutting an opening in the grating

Installation of bird's eye camera / lights /equipment(On the grating)② Removal of grating

Cutting/grabbing/moving the grating③ Removal of interfering objects under
the grating

Cutting/grabbing/moving dikes, verticalpipes, horizontal pipes, supports,
conduits, cables④ Removal of interfering objects
present above the pump pit

Cutting/grabbing/moving vertical pipes,
horizontal pipes, supports, conduits,
cables

⑤ Removal of interfering objects
present around the pump pit

Cutting/grabbing/moving vertical pipes,
horizontal pipes, supports, conduits,
cables

⑥ Investigation of deposits/fuel debris
around the pump pit⑦ Building of dikes around the pumppit

⑧ Measures for ensuring visibility
inside the pump pit⑨ Cutting an opening in the pump pit
cover

Necessity
Not
requiredNot
required

Element test
ReasonNot required as viability has been verified as part of the FY2018 Subsidy
Project (Interference Removal Outside the Pedestal).

Not required as viability has been verified as part of the FY2019 Subsidy
Project (Establishment of Water Circulation System).

Necessity
Not
requiredNot
required

ReasonNot required as viability has been verified as part of the FY2018 Subsidy
Project (Interference Removal Outside the Pedestal).

Not required as viability has been verified as part of the FY2019 Subsidy
Project (Establishment of Water Circulation System).

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Introduction of camera for investigation

Not
required

Not required as viability of work has been verified during the PCV Internal
Investigation

Not
required

Not required as viability of work has been verified during the PCV Internal
Investigation

Building dikes (sand bags, water bags)

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as this work is similar to ②, ③ and has been determined tobe highly viable.

Not
required

Not required as this work is similar to ②, ③ and has been determined to behighly viable.

Remote high pressure cleaning,
installation/removal of sludge pump,installation/removal of diaphragm pump,drainage of muddy water,
supply/drainage of filtered water

Cutting/grabbing/moving of insertion
port for introduction of camera forinvestigation, lights©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.273③ Interference removal from pump pit◼ Selection of element test items a. Selection of test items for the unit tests and element tests (2/2)➢ Test items for the unit tests and element tests were selected from the work steps that were studied.
The test items selected and the reason for selection are given below.

*: Case 2
Fuel debris is present in somepart inside the pump pits

Unit test: Test conducted with a stand-alone equipment outside the simulated environment.
Element test: Test conducted by combining all equipment in a simulated environment.
Work

Unit test

Step

Details

Necessity⑩ Investigation of deposits/fuel debris
in the pump pit

Handling of camera/lights for investigation
inside the pump pit

Required⑪ Cutting of the pump
(Only Case 2)

Cutting/grabbing the pump iIn the pump pit(Case 2)

⑫ Cutting of the bolts used for
installing the pumpCutting of the bolts used for installing thepump, cutting the pump pit cover in the
periphery of the bolts for installing thepump⑬ Lifting up the pump

ReasonElement test
Necessity

ReasonRequired for confirming the conditions necessary for verifying work byconfirming the visibility in muddy water environment.

Not
required

Not required as property of handling will be verified in ⑪ because handlingis determined to be difficult in the case of work performed in ⑪.

Required

Required for verifying the conditions in which cutting is possible in waterusing a tip saw or reciprocating saw.

Required

Required for verifying the conditions for handling of the cutting equipment
and performing cutting work in a confined space using a remote controlled
equipment

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Slinging the pumpNotrequired

Not required as viability has been verified during the installation of actual
facility in FY2019.

Required

Required for verifying the conditions for slinging work carried out by
combining the remote controlled equipment and hoisting equipment.

Lifting up the pump (Case 4)

Required

Required
Required for verifying the conditions for the work of lifting up.

Required for verifying the conditions for the work of lifting up without
interfering with surrounding structures.

Lifting up the upper part of the pump (Case2*)

RequiredMoving the pump (D/W first floor)

Required

Required for verifying the conditions for the work of transferring long andheavy objects (320[kg]).

Required

Required for verifying the conditions for the work of moving without
interfering with surrounding structures.

Cutting of the bolts for installing the pump
pit cover, cutting the pump pit coverNot
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

Not
required

Not required as viability has been verified during the installation of actual
facility in FY2019.

⑮ Installation of D/W water intake
pumpInstallation of pumpNotrequired⑯ Dike removal

Dike removal (sand bags, water bags)

Not
required⑰ Transfer of interfering objects

Transfer of interfering objects up to theequipment hatchNotrequired⑭ Cutting/removal of bolts for installing
the pump pit cover

Required

Not required as viability has been verified as part of the FY2019 Subsidy
Project (Establishment of Water Circulation System).

Not required as viability has been verified during the installation of actual
facility in FY2019.
Not required as viability has been verified as part of the FY2020 Subsidy
Project (Removal of Interferences from Inside the Pedestal).

Not
requiredNot
requiredNot
required

Not required as viability has been verified as part of the FY2019 Subsidy
Project (Establishment of Water Circulation System).

Not required as viability has been verified during the installation of actual
facility in FY2019.
Not required as viability has been verified as part of the FY2020 Subsidy
Project (Removal of Interferences from Inside the Pedestal).

Unit tests and element tests that are determined to be “required” will be conducted to verify viability of work.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.274③ Interference removal from pump pit◼ Study of equipment used a. Study of hoisting equipment➢ The hoisting equipment used at the site, and the hoisting equipment used in the element test were studied.
Further, using the hoisting equipment used in the element test, for the HVH disassembly element test as well, is being
considered.
Outline specifications of the hoisting equipment

Dummy
simulated body

Simulatedpump pit
cover

Pump pit cover
opening(Outside the scope ofelement test)

H

Simulatedpump

Hoisting
equipment

External
dimensions

L2,400×W800×H1,500[㎜] or less(Dimensions that enable passage through the accessroute)

LiftingheightApprox. 6.5 [m] or more

Conveyableweight340 [kg] or more
(Assuming the Unit 2 pump which is the heaviest +hoisting accessories)

Grating cutting equipment (Outside the scopeof element test）

Example image showing the use of the
hoisting equipment on the site
Up to 2,300

Cutting
position•

3,050
Pump pit
simulation

Chain pulley blockwith trolley

Interfering objects for
simulating the dimensions
inside the pump pit

Simulated pump and pump pit (Conceptual drawing)•

Detachable/retractablesupport pole

Hoisting equipment for the element test
(Conceptual drawing)•

Using the same hoisting equipment for the element
test on removal of interfering objects from inside thepump pit, and the HVH disassembly element test, isbeing considered.
Figure on the left (Height 3,050 [mm]) shows thestatus during the HVH disassembly element test.
The height of the hoisting equipment (crane) for HVH
with the jib extended was simulated.
Changing the height of the hoisting equipment during
the element test on removal of interfering objects
inside the pump pit by removing the support pole or
making it retractable, is being planned.
©International Research Institute for Nuclear Decommissioning6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.275③ Interference removal from pump pit: Planned: Planned (after revision)*: Actual◼ Development Process
FY2021

FY2022

Study items
4

Major milestones

5

6

7

8

9

10

11

12

1

2

3

Interim Report▼

45Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

12

1

2

3

Final
report
▼1. Conceptual study

2. Element test planning
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6. Implementation items of this project [1) (2) Development of disassembly and removal technology]

No.276③ Removal of interfering objects from inside the 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 as
preconditions for removing interfering objects from inside the pump pit.
➢ The work steps involved in removing interfering objects from inside the pump pit werestudied, and test items were selected.
➢ Detailed study of the work steps is underway. Illustrations of the work of removing theexisting pump from pump pit (225°) inside PCV in Unit 1 were consolidated.
➢ The simulated pump, pump pit and hoisting equipment to be used for the element test
are being studied. In the future, element test plan including the study on disassembly
equipment, etc. will be developed, and the feasibility of the method for removing
interfering objects from inside the pump pit will be verified by element tests.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This ProjectNo.2771) Development of the side access method
Solicitation items are listed.
(3) Advancement and development of retrieval methods① Remote controlled tip tool for retrieval
In parallel with the study of prospective methods for further increasing the scale of retrieval of fuel debris
and reactor internal structures, evaluation of the throughput is being carried out as well. For enhancing thethroughput of the side access method, it has become necessary to consider optimization of the positioningof 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 to the tip
tools of the remote controlled equipment used for fuel debris retrieval and disassembly/removal of reactor
internal structures, however, tip tools suitable for optimization including the technologies available on themarket will be investigated and consolidated.
In addition, typical techniques pertaining to the tip tools and operation systems (interference avoidanceand control system, etc.) that can be used for works that need to be optimized and improved, will be selectedbased on the requirements for on-site application, and tip tools and operation systems will be test
manufactured for on-site use by making improvements in technologies available on the market or bydeveloping new technologies. With the help of these test manufactured tip tools and operation systems, theprocedures for processing fuel debris and collecting it in unit cans, operability of the tip tools, efficiency, etc.
will be verified by tests using mock-ups (appropriate partial models or scale models are permissible as well)considering the mechanical 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 thethroughput.

©International Research Institute for Nuclear DecommissioningNo.278

6. Implementation Items of This Project [1) (3) Advancement and Development of Retrieval Methods]① Remote controlled tip tool 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[Further increasing the scale of retrieval (Implemented in FY201920)]• Review of side access method for on-site application➢ Study of fixed rail system(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, operation systems• Acquisition of data for throughput evaluation

Combination test of rail
and arm

Study of fixed rail system

Suction andcollection of
granular fuel debris©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]① Remote controlled tip tool for retrieval(1) Development results achieved so far and correlation with this projectNo.279[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, results of theaccessibility test, results of the desk study, etc.
Examples of the processing methods investigated in thepast (excerpts from FY2019-20 reports)
Handling of avariety of fueldebrisProcessing
speed

Accessibility(small head)

Heat input

Fume
emission

Quantity of scraps
produced(dispersion in air)(dispersion in water)

Downsizing ofutilities

Need forsupplyPast processing element tests
FY2014:
・Core boring
・Laser gouging
・Plasma・AWJ
・Laser (shaving)
FY2015-16:
・Core boring
・Laser gouging

Core boring
Circular saw
Wire saw
Band saw(reciprocating saw)

Ultrasonic core drill
Cutter (shears)
ChiselLaser
Plasma arc
Plasma jet

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

Gas
Milling〇: Good△: Satisfactory
×: Unacceptable©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]

No.280① Remote controlled tip tool 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)
Year
FY201516

Processing
methodCore boring

Simulation
・SUS304
・Alumina

Status of test (Installed in the machine tool, etc.)
Alumina

Processing speed
2.86[mm/min]・Outer diameter of cutter:
Φ66mm

Alumina

2.5[kg/h]
・FY2017-18 Estimation
results
The surface after crushing is byand large gray with very few
gaps

FY201718

ChiselCracksProcessing
point

Hole

・Simulated
MCCI

36.7[kg/h]

Chisel B
The whitish portion is
the portion that could
not be crushed.

Chisel A

FY201718

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6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]① Remote controlled tip tool for retrieval(1) Development results achieved so far and correlation with this projectNo.281[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 lack 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 cutting tool, 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
and optimization)[Expected outcome]• Verification of the method for disassembly and removal of structures inside PCV, andprocedures for processing and collecting fuel debris• Acquisition 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]

No.282① Remote controlled tip tool for retrieval(1) Development results achieved so far and correlation with this project[Flow of studies]
Study of throughput improvement measures

Operation system(Interference avoidancecontrol system)

Tip tools
Technical research on tip tools

Conceptual study of the method of
retrieving structures and fuel debris
from inside PCV

Conceptual study of the operation system

Operation system software development

Operation system simulation verification
Tip tools element tests planning
Operation system element tests planning
Designing and manufacturing of
tip tools and test equipment for theelement tests

Tip tools element tests(Processing tests for throughput evaluation)

Designing and manufacturing of operation systemtest equipment

Operation system element tests(Series of operations for throughput evaluation
using the scale model mock-up)

Interfering objects and fuel debris
processing time
Acquisition of data for throughput evaluation

Time required for manipulator work
(Time required for moving andpositioning)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]① Remote controlled tip tool 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 becollected from inside the PCV have been investigated, processing
tests have been implemented, and the throughput has been
estimated based on the results.
• The throughput is estimated based on the processing time
obtained through the processing tests using mainly machine tools,
but the processing time is likely to extend when remote controlled
equipment that lack rigidity are used.
• Therefore, tip tools with specifications suitable for the current
remote controlled equipment (access equipment) will be
manufactured, processing tests will be conducted to improve theaccuracy of the processing time.

Interference removal equipment（Dual motor-operated arms)

Fixed rail type dual motor-operated arms

No.283

Alumina

AluminaCircular cutter

Test piece

Status of past processing tests

Fixed rail type 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 ofRetrieval Methods]

No.284① Remote controlled tip tool for retrieval(2) Background and purpose of this research (Tip tools)✓
Expected outcome of this research, reflection destination, and contribution of the outcome[Expected outcome]• Applicability of the tip tools to the actual equipment, issues and response measures• Data for throughput evaluation➢ Processibility➢ Processing time
➢ Lifetime of the cutting tools• Required specifications of 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 ofRetrieval Methods]

No.285① Remote controlled tip tool 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 remote controlled
robot for fuel debris retrieval, but application to various other works and robots in the future will
be aimed for.
(The environment model and 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 method 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 by veteran 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 ofRetrieval Methods]

No.286① Remote controlled tip tool 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 aspressing force, etc. as parameters, so as to be able to apply the outcome to various 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, but also for testing the lowpressing force assuming smaller access equipment. The processibility will be verified and data forthroughput evaluation will be acquired.
• Tests will be conducted by increasing the current core boring size of Φ66mm in order to reduce theprocessing time for block fuel debris (fuel debris accumulated at the pedestal bottom) which comprises amajor portion of the throughput.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]

No.287① Remote controlled tip tool for retrieval(3) Goals (Operation system)✓ Requirements from the reflection destinations• Reducing the load on the operator
While determination of status or adjustment of the movement speed will be performed by the operator,
complex selections, procedure studies and Wide range monitoring will be left to the system 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 otherworks and equipment in the future. Also, they will be linked to the integrated management system thatis 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 the test
manufactured operation system, the procedures involved in grabbing, cutting and transferring interfering
objects and collecting fuel debris in unit cans will be verified, and viability of a series of operations will be
confirmed. Also, the actual data on the work procedures will be acquired and organized, to create data
for evaluating the throughput.
• 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.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]

No.288① Remote controlled tip tool 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 tip tools and test equipment for the tests• Tip tools element tests➢ Processing tests using 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
No.289Retrieval Methods]① Remote controlled tip tool 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 method of
retrieving structures and fuel debris
from inside PCV

Element test planning

Designing and manufacturing of tip
tools and test equipment for theelement test

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 and sharing information.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]

No.290① Remote controlled tip tool 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 mock-up
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.
Operation
management(2) Remote operation
support system fordecommissioning(3) Decommissioning
work history recording
system

CRD housing

Development ofwork plan
Integrated
management supportWorkauthorization(1) Environmental
modelWork history
Virtual 3D of the insideof
the PCVThis research

CRD housing support
Pedestal
opening

Operation
history

CRD guide tube

Processing
information

Designing ofequipment andwork

Equipment
information

Risk management
history

Sensorinformation

Modification of theactual time in theenvironmental modelContinuous monitoring of theenvironmental parameters (temperature,pressure, dose rate, etc.)
Detailed investigation,
analysis andevaluation of design
information

CRD rail

Platform rotating rail

Changes on the site
Deposits
Implementation ofwork on the site

Measurement andkeeping records ofthe retrieved items

Activities inside and outside the PCV

Legend for the arrows
Main flow of data
Solid line
Dashed line Flow of data due to impact
Double line Coordination between systems

Data utilization proposal by the Fuel debris retrieval monitoring/support/integrated management WG

Height of pedestal
opening:
Approx. 3m

Rotating rail support

Pedestal inner diameter:
Approx. 5m

Height of worker
access port:
Approx. 2m

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 ofRetrieval Methods]① Remote controlled tip tool for retrieval

No.291(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 andpracticality 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 themanipulator with a redundant degree of freedom and its effect was verified.

Upgrading of fundamental technology for retrieval of fuel debris
and internal structures (FY2017-FY2018)“Development of a technique for planning the motion of a multidegree of freedom robot considering avoidance of interferencewith the environment”

During the work of welding the cell adapter to the PCV wall surface in “one stroke”, a route following thewelding 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 ofRetrieval of Debris and Reactor Internal Structures (FY2019FY2020)“Development of technique for remote operation support inenvironments with low visibility and confined spaces”

The trajectory for reaching the goal while avoiding obstacles was created automatically using a computer, thetechnology (trajectory planning) for setting the replay speed through joystick operation by the operator wasdeveloped, comparative verification with past operating techniques (manual operation, teaching) was carriedout 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 have been posted under Advanced Robotics in the Journal of the
Robotics Society of Japan, and is undergoing peer review.)

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 ashort time, wherein when the dual arm type manipulator is being positioned for “grabbing”, “cutting”, etc., orif there is a gap between the 3D model and the actual condition, the gap will be corrected then and there andthe 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 ofRetrieval Methods]

No.292① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Objective• Processing tests will be conducted using tip tools with specifications suitable for the current remotecontrolled equipment (access equipment), data for evaluating the throughput such as processing 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 remotecontrolled equipment (access equipment), whether or not processing is possible will be verified,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 lowpressing force assuming smaller access equipment. The processibility will be verified and data forthroughput evaluation will be acquired.
• Tests will be conducted by increasing the current core boring diameter of Φ66mm in order to reduce theprocessing 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 Development ofRetrieval Methods]① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Implementation items

No.293（a） Study of throughput improvement measures• The throughput estimations from the FY2017-2018 Subsidy Project were analyzed.
➢ Removal of interferences outside the pedestal: 1.731Hr (73 days)➢ Removal of CRD exchanger: 5,543Hr (231 days)➢ Removal of CRD housing: 11,970Hr (499 days)➢ Collection of granular fuel debris: 2,506Hr (105 days)➢ Collection of pebble-shaped fuel debris: 3,560Hr (149 days)➢ Collection of block fuel debris: 44,652Hr (1,861 days)･･･ Of which the processing time was 31,764Hr (1,324
days)• In this development, studies and processing tests will be conducted aiming for reduction in processing time forblock fuel debris (fuel debris accumulated at the pedestal bottom) which comprises a major portion of the abovementioned throughput.
➢ Technical study of new processing methods that have the potential of enhancing processing speed➢ Increasing the current core boring diameter of Φ66mm.
(Example) Throughput of interference removal outside the pedestal
Removalduration
撤去期間

切断片をofCollection
cut pieces in
LLW バスケ
LLW
baskets
ットに回収

Carrying装置搬入

Tool
ツール位

in/out of出equipment

positioning

Processing
加工

1h×2

1h x
number of
1h×切断ブロcut
blocks:
ック数：641
641

Length to be
切断長さ：
cut:
260,750mm /260,750mm／切断速度：
cutting
speed:
86mm/min／
86mm/min/6
60min/h0min/h0.2h x0.2h×切断ブロ
number of
ック数：641
cut
blocks:
641

2h

641h

50.5h

128.2h

置決め

Replacement
セル内で刃of blades
within
the
物交換
cell

LLW バスケbasket
LLW
transfer

Total
合計

Replaced
after
2ブロック切断
cutting every 2
毎に交換
blocks2.5h x 641/2
2.5h×641／2(Carrying-in/out of（ロボットアームrobot arm: 2h)
搬入出：2h）of(Replacement
circular cutter:（ディスクカッタ
0.5h)━

交換：0.5h）

Processing
wait time
加工側の LLW
while theバスケット搬入
LLW
basket待時間
is being
carried-in

801.3h107.8h1,730.8h

ット搬出©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Implementation items

No.294(b) Technical research on tip tools•
So far, many processing methods suitable for the material and shape of items to be collected were investigated, and theirapplicability was studied.
•
SUS and ceramic is 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 were identified as applicable processing methods.

Processing method for fuel debris accumulated at the bottom of the pedestal
Processing method

Applicability

Evalu
ation

Processing everything with a blade to form swarf

・ Can be processed.
・ Will require time△

Processing everything with a chisel to form gravel

・ Whether or not processing is possible depends on the properties of the items to be processed.
・ If the conditions are met, processing is fast.

〇Core boring・ Can be processed.
・ A method of cutting out the reactor core horizontally is required.

〇Cutting out by making intersecting cuts with a circular
cutter・ Can be processed.
・ As work progresses to the second and third stage, the shape of the surface becomes complex and hence
processing becomes difficult.

△

AWJ (Abrasive Water Jet)

・ Can be processed from the viewpoint of material.
・ Processibility of shapes that cannot be penetrated, management of large quantity of abrasive are issues.

△

Laser

・ Can be processed from the viewpoint of material.
・ Processibility of shapes that cannot be penetrated, management of dross are issues.

△

Plasma・ Non-conducting ceramic cannot be processed.

x

Gas

・ SUS, ceramic cannot be processed as oxidation reaction is used.

x〇: Good △: Satisfactory ×: Unacceptable©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]

No.295① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Implementation items(b) Technical research on tip tools• It will be investigated whether or not there is a processing method that has the potential of increasing processing
time for the fuel debris accumulated at the bottom of the pedestal, which comprises a major portion of the duration
for fuel debris retrieval at present.
• While investigations in a wide range of domains such as machine processing, thermal processing, AWJ, etc. areunderway, the focus here will be on the rock excavation method which is yet to be investigated, and information
will be collected from rock excavation tool manufacturers.
➢ Rock excavation handles material that is brittle up to a certain extent. Hence it is not an effective processing
method for material with metallic properties originating from SUS components of the reactor internal structuresin the fuel debris.

➢ Different tools are used for brittle material depending on its hardness. A chisel is recommended for material
with reduced hardness such as MCCI (Molten Core Concrete Interaction) in which concrete is mixed.
Soft: Rock excavation tools
Hard: Breaker (Chisel)
Harder: Blasting・ For using the rock excavation tools, the material to be processed needs to be “brittle”.
・ Not suitable for material with metallic properties such as SUS, etc.
・ A chisel is used for material which is “brittle” and is mixed with concrete.
•

Rock excavation tools are not suitable for fuel debris in which SUS and ceramic are mixed.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Implementation items

No.296(c) Conceptual study of the method of retrieving structures and fuel debris from inside PCV[Tip tools development procedure]
Procedures for collecting structuresand fuel debris
・ Study of collection method

Identification of the functions required of
the tip tools
・ Conceptual designing

Identification of items that needtechnical development from among therequired functions

Technical development (Element tests)

Tip tools for the actual equipment
・ Verification using the access equipment

Study of collection procedures and collection method depending on the position,
shape and properties of the structures and fuel debris

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 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・ Processing technology
element tests
・ Operation system for reducing the load on the operator
・ Dust measures during processing
Verification of viability of a series of operations using equipment anticipating theactual 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 ofRetrieval Methods]① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Implementation items(c) Conceptual study of the method of retrieving structures and fuel debris from inside PCV

No.297[Study of procedures for collecting structures and fuel debris]•
Overview of the current proposal

Interference removal using a telescopic
interference removal equipment (Outside thepedestal)Interference removal using a telescopic
interference removal equipment (Inside thepedestal)(Outside the pedestal)(Inside the pedestal)Interference removal using a telescopic interference removal equipment

Changing to a fixed rail
Chisel B

Interference removal using dual arms

Chisel A

Interference removal using
dual arms

Suction of granular fueldebris using dual arms

Block fuel debris processing
using dual arms

Suction of granular fuel debris using dual arms
Current core boring dimensions: Φ66mm×H100mm（342cm3）
Processing limit of 1 round: 16 cubic cm （4096cm3）

Block fuel debris processing using dual arms

Block fuel debris processing using hydraulic arm

Making a hole atthe centerCore boring

Core cutting

Block fuel debris processing using hydraulic arm©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Implementation items

No.298(c) Conceptual study of the method of retrieving structures and fuel debris from inside PCV[Processing method depending on the items to be collected]• Processing method depending on the location and material of the items to be collected were studied and the following
processing methods were selected.
Processing method 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 fo 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 ofRetrieval Methods]

No.299① Remote controlled tip tool for retrieval(5) Implementation items (Tip tools)✓ Implementation items(c) 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 reactor 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 stage, the shape of the surface becomes complex and hence
processing becomes difficult.

Making a hole at the center by meansof core boring for inserting the circular
cutter, and then cutting the reactor corewith the circular cutter〇: Good processibility at the second and third stage〇: The reactor core can be easily removed.
x： Core cutting and core collection tools other than the core boring tools are required.

Stroke ①

Stroke ②

Adopted based on the processibility at thesecond and third stage

Stroke ③

Stroke ①
Stroke ②Topview

Cutting
blade

Making a hole bymeans of core boringby sliding slightly offset

Top
view

Stroke ④

Bulk to be
removedLateral view
Lateral view

Bulk to be removed

Core boring from 2 directions

Making a hole at the center for inserting the circular cutter ⇒ cutting the reactor
core©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and Development ofRetrieval Methods]① Remote controlled tip tool for retrieval

No.300(5) Implementation items (Tip tools)✓ Implementation items(d) 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 be arranged
and processing tests will be conducted using those tip tools for verifying whether or not processing is possible,
measuring the processing time, and identifying issues.
➢ Dual arms
✓ Payload: 150[kg]✓ Tip tool dimensions: W600×D500×H550[mm]➢ Hydraulic arms
✓ Payload: 2[ton]✓ Tip tool dimensions: W650×D900×H750[mm]Dual arms

Hydraulic arm
Study of tip tool accessibility©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

No.301(5) Implementation items (Tip tools)✓ Implementation items(d) 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 thestudies 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 in thisproject

Processing method

Implementation of element tests during thisproject

Arm
Machine tools*1

Tools*2

Tools*2

Combination with thearm*3

Structure(Interfering objects)

Circular cutter

Dual arms〇-〇(Track record usingarms is present)

Granular fuel debris

SuctionDual arms

-

〇

-

-

Block fuel debris(Brittle portion)

ChiselDual arms

-

〇

-

-

Block fuel debris(Hard portion)

Core boring(Including core cutting)

Hydraulic arm

〇

-

〇

〇
(Combination withhydraulic arm)

*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: 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]① Remote controlled tip tools for retrieval

No.302(5) Implementation items (Tip tools)✓ Implementation items(d) 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 the conceptual design will
be developed.
•
From among the functions required of the processing tools, those related to workability will be verified during the element tests.

Functions required of the tip tools and verification items (1/2)
No.

Work step

Requirements

Content in red : The functions required of theprocessing tools

Required functions

Items to be verified during the element
tests

1

Advanced preparations

1-1

Verification of workability by means A series of operations must be verified at the site by ・Showing the work environment and robot in the form of a 3D
of a simulatormeans of the simulator.
model.
・Being able to operate the 3D model of the robot just like theactual robot.
On-site work2
2-1

Moving from cell → processing The cells must be transferred to the predetermined
location
location while avoiding obstacles by remote operation.
・The dimensions and mass must be such that the robot
arm can be guided.
・ The surrounding environment must be visuallyobserved or confirmed by 3D scanning when the robot
arm is being guided.

2-2

Environment verification

・The dimensions and mass equal to or lower than that whichenables the robot arm to be guided.
・ Visual inspection function
・3D scanning function
・Operation system (Function of assisting the operator)

The condition of the work environment must be ・ Visual inspection function
confirmed by remote operation.
・3D scanning function━━(Tip tools designed with dimensions
and mass equal to or lower than thatwhich enables the robot arm to be
guided.)━Circular cutter
2-3

2-4

Gabbing the items to be removed

Processing the items to be grabbed

Remote operation must be conducted to position the tip ・Grabbing function
tool and grab the items to be removed.
・Function of following the same pattern for the items to be
grabbed・ Visual inspection function
Remote operation must be conducted to position the tip
tool and process the items to be removed.
・The blade must be cool.
・Dispersion of machining dust must be reduced.

・Processing function
・Function of verifying the processing status (Speed of the
motor, etc.)
・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) and processing time・Life of blade
・Processing reaction force (requiredpressing force)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of retrieval methods]

No.303① Remote controlled tip tools for retrieval(5) Implementation items (Tip tools)✓ Implementation items(d) 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 the element
tests

suction2-5

Suction of granular fuel debris

Remote operation must be conducted to position the tip ・Suction function
tool and suck granular fuel debris.
・Function of verifying suction status (Status of pump operation,
etc.)
・Visual inspection function (Verification of surrounding
environment and suction status)
・Operation system (Function of assisting the operator)━

Chisel2-6

Processing the items to be grabbed

Remote operation must be conducted to position the tip ・Processing function
tool and process the items to be removed.
・Visual inspection function (Verification of surrounding
・Dispersion of dust must be reduced.
environment and processing status)
・Dust reduction function (Water supply, etc.)
・Operation system (Function of assisting the operator)━

Core boring (Including core cutting)
Remote operation must be conducted to position the tip
tool and process the items to be removed.
・The blade must be cool.
・Dispersion of machining dust must be reduced.

・Processing function
・Function of verifying the processing status (Speed of the
motor, etc.)
・Visual inspection function (Verification of surrounding
environment and processing status)
・Blade cooling function
・Dust reduction function
・Operation system (Function of assisting the operator)

2-7

Processing the items to be grabbed

2-8

Leaving behind the items to be Remote operation must be conducted to transfer the ・Same as 2-1
removed / storing in container
items to be removed.
・Same as 2-1

・Whether or not processing ispossible (including cooling of blade)・Processing conditions (speed, torque,pressing force) and processing time・Life of blade
・Processing reaction force (requiredpressing force)
・Work in combination with the arms
(Stand-alone tool for 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)✓ Implementation items(d) Element test plan

No.304[Simulated bodies for the element tests]• The simulated bodies used in element tests so far were not changed. The following were selected based on the properties andavailability of material derived from fuel debris.
➢ Interfering objects: SUS, SUS + Alumina➢ Fuel debris: SUS + Alumina
・ SUS simulates the material of reactor internal structures.
・ Alumina is selected as material which is highly hard and easily obtainable, from among the ceramic material that is
considered to be similar to fuel components.
・ In the case of SUS+Alumina, 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: 15.2GPa, Zirconia: 12.3GPa[Acquired data]• Processing tests (Refer to the next page onwards) will be conducted for each tip tool (circular cutter, core boring) toobtain the following data.
➢ Applicability of the tip tools to actual equipment, issues and response measures➢ Workability➢ Processing time
➢ Life of the blade➢ Requirements of the remote controlled equipment (Access equipment)✓ Processing reaction force (Required tip tool pressing force)➢ Workability in combination with the arms (Core boring)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of retrieval methods]

No.305① Remote controlled tip tools for retrieval(5) Implementation items (Tip tools)✓ Implementation items(d) 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.
➢ The mass is set at 100kg considering the mass of cables and hoses since the payload of the dual motor-operated arms is
150kg.
It is assumed that the grating,➢ The size that can be cut is set at 150mm based on the dimensions of the structure to be cut.
beam, and CRD exchanger will
be cut.

Specifications required of the circular cutter for the dual motor-operated arms
Required functions

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: Motor that can be mounted on the tool is selected
Cutter speed: Motor that can be mounted on the tool is selected

Cooling of the blade

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 ofpart to be processed

Installation of cameras and lights©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)✓ Implementation items

No.306(d) 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 functions of theactual equipment
Circular cutter
Feed direction

Direction ofrotation

Tools
CylinderMotor for rotating
the cutter
Circular cutter

Cooling water
nozzleIllustration of
actualequipment

・SUS
・SUS +
Alumina

Motor
Material being processed

Illustration of test
equipment

・ 4 layers of SUS304 （t5mm） and Alumina （t5mm） stacked

Sample image oftesting

Processing time・ Processing test will be conducted with the type of blade, speed, torque, pressing
force as the parameters.
・ Workability, processing time, 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]

No.307① Remote controlled tip tools for retrieval(5) Implementation items (Tip tools)✓ Implementation items(d) 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.
➢ The payload of the 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 such conditions andprocessing (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 the blade.
Conceptual planning of the actual equipment based on the specifications required of the actual equipment

Motor forrotating thecutter

Cylinder forsending in the
cutterOutrigger

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)✓ Implementation items

No.308(d) Element test plan[Study of test items and testing methods]
Core boring (Stand-alone tool + combination with arm)

It is assumed that a hard layer ofblock fuel debris will be cut.

Specifications required of the core boring for hydraulic arm
Required functions

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: With Φ66mm which was used in the element tests in the past as reference, it isassumed that the size will be increased (about Φ100mm) in order to shorten the schedule.

Rotational torque of cutter: Motor that can be mounted on the tool will be selected
Cutter speed: Motor that can be mounted on the tool will be selected
Cutter pressing force: Maximum 2 ton (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

Supply of machining water to the portion to be cut

Visual inspection ofpart to be processed

Installation of cameras and lights©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)✓ Implementation items(d) Element test plan

No.309[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(cylinder)

Illustration of the arm combination test
・SUS +
Alumina

Material being processed(t10mm)・ Workability using the arm will be verified underconditions determined during the unit test.
(The impact of the rigidity and vibration resistance of
the arms will be verified）

Illustration showing the tool unit test
equipment

Alumina

Processing time・ Processing test will be conducted with the type of
Aluminablade, speed, torque, pressing force as the parameters.
・ Workability, processing time, life of the blade will beverified.
It is assumed that a hard layer ofblock fuel debris will be cut.
Load

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)✓ Implementation items(d) Element test plan

No.310[Study of test items and testing methods]

Core cutting (Only tool)•

The specifications required of the actual equipment will be identified for designing the equipment for the element test.
➢ The target mass will be set at 100kg similar to the circular cutter so that either one of the dual motor-operated arms or
hydraulic arm can be handled.
➢ Cutting will be performed while holding the reactor core so as to make it easier to remove the reactor 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: Motor that can be mounted on the tool is selected
Cutter speed: Motor that can be mounted on the tool is selected
Cutter pressing force: Being examined
Receiving of the cutter pressing force reaction force: Installation of core clamp

Cooling of the blade

Cooling water supply for cutter

Dust control

Supply of machining water to the portion to be cut

Visual inspection ofpart to be processed

Installation of cameras and lights©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)✓ Implementation items

No.311[Study of test items and testing methods](d) Element test planCore 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 clamp 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
Motor forrotating thecutter

Cylinder forsending in the
cutterCircular cutter

Tool

CylinderFeeddirection

Direction ofrotation

SUS + AluminaCore clamp
Motor

Material being processed

Circular cutter
Illustration of actual
equipment

Illustration of test
equipment

Sample image of testing

Step 1: For setting the processing conditions

Motor

Core is clamped(Can be retrieved)

Circular cutter

Illustration of the actual
equipment test

Core

Processing time・ Processing test will be conducted with the type of blade, speed,
torque, pressing force as the parameters.
・ Workability, processing time, life of the blade will be verified.

Load・ Since preparation for halving theround bars (Alumina) of the size ofthe outer diameter of the reactor
core is not an easy task, it will be
replaced with square shaped blocksof the size of the outer diameter ofthe reactor core.

・SUS

Step2: 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 thereactor core is clamped.)・ Performance of the reactor 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.312① Remote controlled tip tools for retrieval(5) Implementation items (Tip tools)✓ Outcome (FY2021)• Procedure for collecting and method of processing the structures and fuel debris inside PCV.
• Concept of tip tools for actual equipment that consider specifications of the access equipment• Processing element test items and testing methods✓

Contributions of the outcomes to the reflection destinations (FY2021)• Concreteness of the fuel debris retrieval methods was enhanced through conceptual studies on
tip tools for the actual equipment.

✓

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. (Reference: No. 300)
• The properties of fuel debris are unknown, but SUS is selected for simulating reactor internal
structures and Alumina is selected for simulating fuel components, and assuming that these are
mixed at the site, processing SUS and Alumina simultaneously will be tested. (Reference: No.
304)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of
retrieval methods]

No.313① Remote controlled tip tools for retrieval(5) Implementation items (Tip tools)✓ Level of achievement compared to the goal
• Test manufacturing of tip tools with specifications suitable for the remote controlled equipment(access equipment) that is currently assumed⇒ ・ Conceptual study of the tip tools for the actual equipment is almost complete.
・ Equipment for testing is being planned based on the results of the conceptual study of tip
tools for the actual equipment.
• Processing tests with the processing conditions extensively considered as parameters⇒ ・ Test parameters and test cases are being studied.
✓

Future plans• Designing and manufacturing of the element test equipment (up to September 2022)• Verification of whether or not processing is possible by element tests, measurement ofprocessing time (up to December 2022)• Development of data for throughput evaluation, identification of issues (up to February 2023)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of retrieval
methods]

No.314① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Objective
The load on the operator will be reduced and work efficiency will be enhanced by means of theoperation system that 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 beverified. 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 beconsolidated 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 bymeans of mock-up tests• Acquisition of actual data on the work procedures, creation of data for throughput evaluation✓ Outcome (FY2021)• Study of work procedures for interference removal, requirement definitions of the operation systemand test manufacturing©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

No.315(5) Implementation items (Operation system)✓ Implementation items⚫

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
FY2021 Implementation Items➢ Development of operation system➢ Verification of effectiveness bymeans of element tests ⇒Verification of operating time of the manipulator throughFigure 1 Illustration of theinterference removal work in Unit 3

Arm tip

Obstacles

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

Base
Figure 2 Evasive maneuvering of themanipulator 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 (Operation system)✓ Implementation items

No.316⚫ Work flow of fuel debris retrieval using the operation system (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 set 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 using physical simulation, etc. will need to be studied separately.
・ There are two kinds of removal procedures, namely, “Removing sequentially from the front” and “Removing while avoiding
obstacles”. The level of difficulty of the latter is high.
(Issues that have a higher level of difficulty will be set)©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 (Operation system)✓ Implementation items

No.317⚫ Work flow of fuel debris retrieval using the operation system (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.318
6. Implementation Items of This Project [1) (3) Advancement and development of retrieval methods]① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Implementation items⚫

Work flow of fuel debris retrieval
using the operation system
Work plan⓪ Prior verification ofwork(Using the simulator)② 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.

① Moving inside thepedestal

A：Movement end pointin the trajectory plan

B：Grabbing point

On-site work

② Grabbing andcutting the items to be
removedC：Movement end pointin the trajectory plan

③ Transferring ofitems to be removed
outside the pedestal④ Leaving behind thetransferred items to be
removed / storing incontainer

D：Cutting end point

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] No.319① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Implementation items⚫

Work flow of fuel debris retrieval
using the operation system③ 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)

Work plan
Inside the pedestal⓪ Prior verification ofwork(Using the simulator)① Moving inside thepedestal

On-site work

② Grabbing andcutting the items to be
removedItems to be removed

Separate trajectory plans will be madefor the onward route and the returnroute.
・ As part of the environment changes
・ As the robot model changes④ Leaving behind the items to be removed (structures/fuel debris) at the PCV bottom / storing in unit cans・ “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 rightfigure)(The method of determining whether or not fuel debris is adhered needs to be established separately.)③ Transferring ofitems to be removed
outside the pedestal④ Leaving behind thetransferred items to be
removed / storing incontainer

Left behind at the PCV bottom

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 (Operation system)✓ Implementation items

No.320Overview of the trajectory plan developed until last year
The flow of handling the trajectory plan is indicated with a block diagram.
This function has made it possible to move the manipulator such that it does
not collide with obstacles.

Information on the robot andenvironment

Trajectory plan algorithm

Robot

•

Route computation up to thedestination

Motor for each joint•

Determination of collision
with the robot model and theenvironment model →Computation of position sothat both do not interferewith eachother• 3D model of the robot• 3D model of the environment
Registeredin advance

Goal isdetermined.

Route up to thegoal is output

Target angle ofeach joint is
outputServo controller
Order to each joint

Integrated controller

Operator manipulates the replay speed

Operator(Note) Joint research with Kobe University

Camera images, etc.
©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

No.321(5) Implementation items (Operation system)✓ Implementation items
Issues with the trajectory plan⚫

As the work of high accuracy positioning such as for grabbing, cutting, etc. isswitched over to manual operation, the risk of collision 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, the operation needs to be
switched to manual operation.
⇒ As manual operation heavily relies on the skills of the operator, the risk ofcollision 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.

Illustration of work of grabbing by hand

⚫ 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.

Start

Obstacles

Goal

Point of division©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of retrieval methods]

No.322① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Implementation items
Measures to resolve the issues with the trajectory plan
A “Local trajectory plan” will be added to the system as a measure for resolving the issues.
To differentiate the plans, the trajectory plan that was referred to until now will be called “Wide range trajectory plan”.
Wide range trajectory plan (trajectory plan referred to until now)
Start

(Example of 4 segments )Local trajectory plan
Current location
Position after
0.1 seconds

Goal
Conceptual drawing

Route computation
Determination of collision
Computation time

A series of movements from start to the goal (rough)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)(Note) Joint research with Kobe University

Real time (Sequential computation as the robot moves)

Meticulous interference avoidance is possible by repeating the “Local trajectory plan”.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of retrieval methods]

No.323① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Implementation items
Example of using the Local trajectory plan ①
The risk of collision increases with manual operation ⇒ Collision is avoided by means of the “Local trajectory plan”
Position in which the robot and theenvironment do not interfere with eachother (Each axis value is arranged)

Information on the robot
and environment•

3D model of the robot•

3D model of theenvironment

Local trajectory plan

[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
Arbitrary movement(Issuing instructions for the
position of the arm tip)
[Control of breakup rate]

Past operating
methodOperator

Past operating method

Simulatedmovement

Local trajectory plan

Evasive maneuvering of the elbow

Obstacles

The elbow collides withthe 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]

No.324① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Implementation items
Example of using the Local trajectory plan ②
Obstacles are likely to be missed ⇒ Obstacles will not be missed by means of the “Local trajectory plan”
Information on the robot andenvironment•

3D model of the robot•

3D model of theenvironment

Robot

Local trajectory plan

Wide range trajectory plan
Rough trajectory

Consists of 2 stages comprising creation of aseries of events from start to the goal (roughtrajectory) based on the Wide range
trajectory plan, and then interpolation of thegaps by the Local trajectory plan.

Route up to thegoal is output

Goal isdetermined.

Detailed
trajectory
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 basedon the Wide range trajectoryplan

Obstacles

Detailed trajectory basedon 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

No.325(5) Implementation items (Operation system)✓ Implementation items
Element test plan (Simulation tests + mock-up tests)
Work plan⓪ Prior verification ofwork(Using the simulator)① Moving inside thepedestal

On-site work

② Grabbing, cutting*the items to be
removedSimulation tests•
The effect of the Local trajectory plan will be verified using thesimulator.
•
Whether or not “Prior verification of work” is possible will be verified.
(Verification in an ideal environment where there are no errors, delays, etc.)

Mock-up tests(Verification of validity in real environment where there are errors, delays,etc.)•
The real time performance, remote operability of the Local trajectory
plan will be verified.
•Handling of errors in the environmental model and site (mock-up) will
be verified.
The operator remotely operates the robot while seeing only the monitor

Status on site
(The operator does not see)③ Transferring ofitems to be removed
outside the pedestal④ Leaving behind thetransferred items to be
removed / storing incontainer

Fuel debris retrieval work flow
• As “cutting” is performed during the processing tests on the tip tools,
only minute movements by the manipulator are simulated here.

Operator console (Sample image)

Test equipment (dual arm-type robot) and mock-up(Sample image)©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

・As “Performing work while avoiding obstacles with the help of the multi-jointed (articulated)
manipulator” will be verified, interference removal with the help of the dual arm type robot will besimulated as one of its example.
However, the system to be developed is intended for used in various robots and its
application is not limited to interference removal.

(5) Implementation items (Operation system)✓ Implementation items
Mock-up test plan••

No.326

Test equipment with an axial configuration close to that of the interference removal equipment will be used. (The linear motion of the access rail is substituted by the forward
movement of the trolley)
A scaled down mock-up will be prepared in accordance with the ratio of the test equipment, as the workability of the interference removal equipment will be simulated.

Pedestal
opening

Inside the pedestal

Interference
removal equipment

Items to be removed

Pedestal
opening
Interference removal equipment [Under examination]

Mock-up test equipment (Upper floor decontaminationequipment)

Manipulator x 2

Manipulator x 2
External
appearanceof equipment

Rotation and inclination mechanism

Access rail

Main
specifications

Manipulator: 8 axes × 2 types
Rotation and inclination mechanism: 2
Access rail: 2 (Extension and inclination)

As the movement of theaccess rail that approaches
from diagonally above will besimulated, the mock-up will
be installed tilted 15 degrees.
(The trolley moves forward
on the ground)

Trolley
Manipulator: 8 axes × 2 types
Inclination mechanism: 1, Rotation mechanism: 1(Additionally installed)
Trolley：2 (Forward motion and rotation）©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

No.327(5) Implementation items (Operation system)✓ Implementation items
Details of verification by means of mock-up tests“Removal while avoiding obstacles” which has a higher level of difficulty will be set as the issue.

Pedestal
opening

The work of removing interferences from outside the pedestal will be simulated.
(Interfering objects will be left behind at the PCV bottom)
Items

Location whereinterfering objects
are left behind
Laser scanner

Details of verification

Passing through the pedestal opening

・Onward route: With only the tool mounted at the arm tip
・Return route: With the interfering object held in the hand tool

Recognition of the environment

・Scanning the environment with the laser scanner mounted at the arm tip
・Responding to errors by comparing the point cloud data and the 3D
model

Disposing of collected items

・Placing them at the disposal area outside the mock-up (interfering
objects)
・Storing in simulated unit cans (pebble like simulated fuel debris)Interfering
objects

Holding of interfering objects and scanning (Illustration)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of
retrieval methods]

No.328① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Contribution of the outcomes to the reflection destinations[Outcome]: Automation of interference avoidance by the manipulator[Reflection destination]: Development is carried out for application to the remotely operated robot used for fueldebris retrieval, but application to various other work 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
operation 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 by veteran operators, and a reduction of approx.
80% in the time required for creating teaching data. The previous project will be implemented and advanced further inthe 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. (Reference: No. 325, 326, 327)
• 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. (Reference: No. 290, 325, 326, 327)

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of
retrieval methods]

No.329① Remote controlled tip tools for retrieval(5) Implementation items (Operation system)✓ Level of achievement compared to the goal
• Test manufacturing of the operation system → Simulation verification underway• Study of grabbing/cutting/transfer of interfering objects → Implemented• Verification of a series of operations → Will be implemented through mock-up tests• Acquisition and consolidation of actual data on work procedures → Will be implemented through mock-up
tests• Creation of data for throughput evaluation → Will be implemented through mock-up tests• Consolidation of case studies on the operation system application conditions, assumed issues, etc. →Being implemented✓ Future plans• Mounting of operation system on the element test equipment (Up to September 2022)• Manufacturing of the mock-up (Up to September 2022)• Verification of viability of a series of operations by means of mock-up tests (Up to December 2022)• Acquisition of actual data on the work procedures, creation of data for throughput evaluation (Up to
February 2023)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and development of
retrieval methods]

No.330① Remote controlled tip tools for retrieval(6) Summary
Tip tool➢ Throughput computations from the past were analyzed, and processing tests for
reducing the time required for processing block fuel debris accumulated at thepedestal bottom were selected as element tests.
➢ Circular cutter for interfering objects, core boring for block fuel debris, which havenot undergone processing tests as a tool, were identified as element test items
based on the status of implementation of past desk studies and processing tests.
➢ The specifications required of the above-mentioned tools have been consolidated
and conceptual studies and element test planning are underway.

Operation system➢ The fuel debris retrieval work flow was studied, and the functions required of theoperation system were consolidated.
➢ An operation system that supports remote operation by the operator was developed,
and simulation verification was carried out.
➢ In the future, the effect of the operation system is planned to be verified by means ofmock-up tests.
©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [1) (3) Advancement and developmentof retrieval methods]

No.331① Remote controlled tip tools for retrieval(7) 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

Interim Report
▼

11

12

1

2

3

Final Report▼

Study of throughput
improvement measures

Tip tool element testplanning and preparation
Element tests (Processing
tests for throughput
evaluation)

Time required for processing interfering
objects and fuel debris

Study of operation system

Development of theoperation system andsimulation verification
Element tests (Series ofoperations using theoperation system)

Time required for manipulator work
(Time required for moving, positioning, etc.)

Throughput evaluation
Creation of report

Remarks

A panel of experts met on July 13, 2021 and February 8, 2022 in connection with the operation system. A meeting of the panel of experts is planned to be held again as
required depending on the progress.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project2） Development for the top access method

No.332
Solicitation items are listed.

(1) Development of technology for realizing the concept of retrieving large structures① Method of cutting into 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 establishingthat method, structures need to be cut out and transferred. However,during the work of cuttingout, reactor internal structures that comprise a variety of equipment from steam dryer tosparger, shroud, jet pump, etc. need to be cut in a high-dose radiation environment and in aconfined space inside the reactor, and transferred. Also, the method of cutting and transferringlarge structures other than the reactor 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 tobe studied.
As it is presumed that the fuel has melted and is present inside the RPV, a method of cutting
and separating while taking into consideration metallic reactor internal structures and ceramicfuel debris, will be studied, and element tests will be conducted using simulated test pieces.
Also, the method of transferring structures after they have been cut, including the PCV head,etc. until the structures are loaded on to the large transportation 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.333Development 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

Project of Further Increasing the Retrieval Scale of Fuel Debris(Implemented in FY2019- 20)

This project[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

Upper lid
Being developed under
the Ensuring Safety PJ

Work
container

Container
dual lid

Lower lid

Large transfer
container

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)[Development of isolation technology to prevent the
spread of contamination]➢
Development of isolation technology andelement tests

Scope of studies
conducted in this project

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➢

Shielding cart

Method of fine cutting
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ノズルAWJ
nozzleRemovalof large structures at the
炉底部の大型構造物の撤去
reactor bottom

Study of developmental issues identified during engineering andtechnical development, etc.
隔離シート
Isolation

sheet

FY2019-20
Study on cutting the reactor bottom partand 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
retrieving large structures]
Development of technology pertaining to items in red will No.334
be carried out in this project① Method of cutting large structures
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 structures
走行
Disassembly
解体装置
equipment

Crane for

切断片取り
handling cut
扱い揚重機
pieces

駆動モータ(連絡通Drivemotor (outside
the passageway)
路外）

Disassembly
解体装置
equipment

Disassembly
equipment

解体装置

Hoisting
切断片吊accessories
forり具
the cut pieces

Shroudシュラウド
head bolt
ヘッドボルト

PCV
ＰＣＶ上蓋
upper
lid

Isolation sheet
Cutting
切断マニ
manipulator
ピュレータ

Cutting
切断マニ
manipulator
ピュレータ

Separator
セパレータ

Stud bolts
スタットボルト

Implementation of conceptual study of the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)

Development of isolation technology to preventthe spread of contamination (FY2021-22)

Isolation sheet

Method of cutting structures other than reactor
internal structures

Transportation
cart

Shielding cart

Illustration of filling andcutting

Solidification
by filling

Large transportation equipment

Dual lids

Work container

Shroud gripper

シュラウド把持部(Making a hole andgrabbing)（穴加工し把持）Cutting②

Trapezoidal screw drive
system
Implementation of conceptual study of the Further
Increasing The Scale of Retrieval PJ (FY2019- 20)

Air tight mechanism with dual lids

Method of cutting the reactor internal
structures

Cutting①

screw

Endless roller system

PCV

RPV上蓋
upper lidCutting
切断マニ
manipulator
ピュレータ

Guide
ガイド
Trapezoidal
台形ネジContainer Large transfer
dual lid
container
Shroudシュラウド

Cutting(2)
切断②Element tests for the Ensuring Safety PJ(FY2020-21) are being planned

Cutting
the entire
断面全域の切断
cross sectional area

ワイヤー
Wire saw 切断機
cutterCutting structures of the reactor bottom

Large transfer container

Cutting tool
切断ツール
transportation
搬送装置
equipmentCollection container
回収容器
transportation
搬送装置
equipment

Auxiliary arm

Auxiliary
arm
補助アーム

Grating
グレーチング
insulating
保温材
material

Cutting
tool (With
切断ツール(把持と切断機能あり)
grabbing andcutting functions)

Fuel debris at thereactor bottom

Lower
hemisphericaldome opening

7m

RPV lower
RPV下鏡
hemispherical
dome

CRD
supportCRD.Hサポート
beam,
bracket
ビーム、ブラケット

Simulation of collapsed Filled with geopolymer(Inner diameter of container 300mm）
CRGT

Implementation of element tests pertaining to the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)

Φ6m

HCU配管
HCL
pipes
信号ケーブル類
SignalcablesIllustration of the work 炉底部干渉物撤去作業イメージ
of removing interfering objects from the reactor bottom

Implementation of element tests pertaining to the
Further Increasing The Scale of Retrieval PJ (FY2019- 20)

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 theconcept of retrieving large structures]① Method of cutting large structures

No.335[Issues]•
Structures need to be cut and transferred in a high-dose radiation environment and in a
Crane (passageway)
confined 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 conducted in this projectneeds to be verified.
Connection sleeve(Connecting the PCV and[Implementation details]
the passageway)
・Preconditions for the studies will be consolidated.
・Method and procedures for cutting and transferring reactor internal structures and structuresother than the reactor internal structures will be studied.
Structures other than the・With the method of filling and solidification of fuel debris in mind, the methods for cutting andseparating structures that are a mixture of metallic and ceramic material including the filler
material will be studied for retrieving reactor internal structures, element tests will be planned
and implemented, and feasibility will be verified.
・ The methods of cutting large structures such as the PCV head, etc. will be studied based on
the studies on the connection sleeve to which structures other than the reactor internal
structures are joined inside the reactor well, element tests will be planned and implemented,
and feasibility will be verified.
・ The methods for transferring structures after they have been cut, including the PCV 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 thelarge transportation equipment

reactor internal
structures (PCV head,
RPV head, etc.)

Reactor internal
structures (Dryer,
separator, shroud, fueldebris, etc.)

FY2019-20
Study of methods for cutting thereactor 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
retrieving large structures]① Method of cutting large structures

No.336[Implementation details]
Implementation items
Consolidation of preconditions

Implementation details
Preconditions pertaining to the methods for transferring unitized large structures will beconsolidated.

Study of the methods for transferring
unitized large structures

Methods and procedures for cutting and transferring reactor internal structures and structuresother than the reactor internal structures will be studied.
・The methods for transferring structures after they have been cut, including the PCV head, etc.
until the structures are loaded on to the large transportation equipment, will be studied, and theirsite applicability will be evaluated.

Structures otherthan reactor internal
structures

The methods of cutting the PCV head, RPV head, etc. inside the reactor well such that unitizedlarge structures can be transferred will be studied, and conceptual study of the equipment will be
conducted.

Reactor internal
structures

・The methods of filling that consider the conditions of the actual equipment will be studied inconnection with the method of filling and solidifying fuel debris and then transferring it to preventthe reactor internal structures from falling.
・The methods of cutting including the shroud structures and filling material after filling material isfilled, will be studied.

Structures otherthan reactor internal
structures

・ Element tests will be planned and implemented pertaining to the method of cutting RPV head
which is assumed to have a higher level of technical difficulty, from among the methods of
cutting large structures for the structures other than the reactor internal structures, and thefeasibility will be verified.

Reactor internal
structures

・Element tests will be planned and implemented for ascertaining the properties of the filling andsolidification material through large scale filling tests, with an increased scale as compared toprevious basic tests, and feasibility will be verified.
・Element tests will be planned and implemented pertaining to the cutting method including
shroud structures and filling material, and feasibility will be verified.

Study of themethods for
cutting large
structures

Element tests
planning andimplementation©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.337[Preconditions for the methods for transferring unitized large structures]• Pre-conditions pertaining to the methods for transferring unitized large structures are indicated below.
ID.

Preconditions

Evidence

Remarks

1

An additional building for the top access methodshould be installed in addition to the additionalbuilding 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 incommon with the side access fuel debris
retrieval method.

2

A frame structure should be installed so that theload of the passageway in which retrieval
equipment, etc. will be installed is supported by
the ground surface.

Considering the acceptable maximum load of
the operation floor, it will be difficult to support
the load of the passageway.

3

After transferring the unitized RPV head, the load
should be applied for retrieval equipment thesurface of the RPV head flange.

At the current stage, since the RPV head isbeing supported, it is assumed that load can beplaced after the RPV head is retrieved.

4

A method for transferring the largest size as
much 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 most difficult to handle.

Revision of the transfer
dimensions are depending on thestatus inside the reactor.

5

Cutting policy of the connecting parts such as
bolts should be considered.

The cutting policy should be studied
considering the possibility that connecting parts
such as bolts, etc. may not turn due todeformation, galling, etc.

Whether the bolts should be cut
or loosened needs to beevaluated depending on theactual conditions.

6

Large transfer containers should be used fortransferring structures.

The policy of preventing spread ofcontamination should be maintained by usinglarge transfer containers.

©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.338The development for the method of cutting large structures is bieng carried out by dividing it into thefollowing 3 items.
The status of current studies and the cotents of the report this time are indicated below.
Implementation details

Status of study

Contents of report(a)Study of the methods fortransferring unitized large
structures

The methods for transferring unitized large
structures are being studied including themethod of application of the isolation sheet thatis currently being implemented in anothersubsidy project (Isolation Technology PJ*).

Overall steps are being
studied.
Details will be reported in
the future.

(b)

Study of the methods for cutting
large structures other thanreactor internal structures,planning and implementation ofelement tests

The methods for cutting the stud bolts of the
RPV head from among the structures inside thereactor well were studied, and element tests
were implemented.

Test results(c)Study of the methods for cutting
reactor internal structures intolarge pieces, planning andimplementation of element tests

Conceptual study pertaining to the methods for
cutting reactor internal structures will be
conducted, element tests will be planned in the
future.
Tests for ascertaining the properties of the fillingand solidification material have been planned,
and are being implemented.

Status of study*Isolation Technology PJ： “Development of fuel debris retrieval method (Development ofisolation technology to prevent the spread of contamination during retrieval andtransportation 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
retrieving large structures]① Method of cutting large structures (b) Other than reactor internal structures

No.339[Study of the methods for cutting the RPV head into large pieces]
It is assumed that it would be difficult to loosen the RPV head bolts due to corrosion, deformation, etc. ofthe screws, hence the bolts would need to be cut. The locations where the bolts would be cut werestudied.
Proposal 1 Cutting
the bolt heads<RPV upper lid>

Proposal 2 Making a cut inthe flange(As deep as the bolt location)

Proposal 3
Cutting the bolts
from the upper lid flange gap

PCV upper lid
Making acut

Cutting
Making a cut

The structure ispresent at thesame level andhence it isdifficult for theequipment toaccess it

Stud bolt

Pulling up
Stud bolt* It is anticipated that it would
be difficult to loosen due todeformatio, corrosion, etc. ofthe screws

Galling islikely tooccur due
to corrosionof the bolt
jointsAWJ cutting

Pulling up
Minimizationof the scopeof the joint

Cutting such that the flange sheet
surface does not get perforated.

● Even if the cutting is performed where the nut is positioned, pulling it up would be difficult as it is a stud bolt.
Proposal 3 in which galling of the bolts does not occur while lifting up RPV upper lid was selected as the primary proposal, and it was decided to verify the viability of AWJ
cutting.
©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 (b) Other than reactor internal structures

No.340[Steps involved in RPV head bolt cutting in the actual equipment]
Work steps involved in RPB head bolt cutting in the actual equipment, and the items to be verified bycorresponding element tests are studied.
1. Carrying-in the work container, installing apolar crane: Scope of simulationin element tests

2. Positioning the cutting tool

Installation of work
container A

3. Cutting the bolts

RPV flange
surface
Auxiliaryarm

Cutting tool(With line laser)

Illustrationof work
steps
Polar crane➢➢RequiredfunctionsMain
issues

Proposedcounterm
easures

Transportation
cart

It should be possible to safely transport the work container A
up to the opening.
It should be possible to prevent outflow of radioactive materials
from inside the reactor and inside the work container into the
cell.

➢
➢
➢

It should be possible to launch the cutting tool into the target spot
while avoiding interfering objects.
It should be possible to position the cutting tool on the RPV flange
surface.
It should be possible to implement the above-mentioned operations
remotely and in the dark.

➢
➢
➢
➢

It should be possible to adjust the AWJ nozzle in the gap with
the RPV flange.
It should be possible to cut the bolts along the flange surface
undergoing AWJ cutting.
It should be possible to verify that cutting has been completed.
It should be possible to implement the above-mentioned
operations remotely and in the dark.

① Measures against overturning of work container② Development of transportation technology that does notinterfere with the gate between the cells③ Ensuring air-tightness from inside of the reactor, inside of thework container to outside the work container① Avoiding of interfering objects during remote operation② Positioning of the cutting tool while monitoring with cameras③ Cable routing for equipment inside work container A① Adjustment of the position of the AWJ nozzle while monitoringwith cameras② Setting of a scanning route suitable for the object to the cut③ Verification of completion of cutting by means of cameras④ Selection of processing conditions for enabling cutting of bolts① The transportation method is being studied using largetransportation equipment.
② Ensuring air-tightness by means of the isolation sheet is being
studied under another subsidy project.

① Verification of suitable placement of cameras through element tests② Verification of whether or not the position can be confirmed by meansof line laser, through element tests③ Study of equipment configuration that would enable cable routing
inside the work container in accordance with downward movement of
the cutting tool/auxiliary arm① Verification of whether or not the position of the AWJ nozzle
can be adjusted by means of the cameras, line laser, throughelement tests② Verification of whether or not the scanning route of the nozzle
can be confirmed before processing, through element tests③ Verification of whether or not completion of cutting can be
confirmed, through element tests④ Verification of processing conditions for cutting the bolts,
through preliminary tests©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 (b) Other than reactor internal structures

No.341[Steps involved in RPV head bolt cutting in the actual equipment]
Work steps involved in RPB head bolt cutting in the actual equipment, and theitems to be verified by corresponding element tests are studied.
4. Collecting the cutting tool

5. Replacing the work container

Installationof work
container B

Polar cranedisassembly
equipment, work
container A

➢
➢
➢

Fuel
exchange
bellowscover

It should be possible to collect the cutting tool while avoiding
interfering objects.
It should be possible to wind the cables as the cutting tool is raised.
It should be possible to implement the above-mentioned operations
remotely and in the dark.

①

Main
issues

Proposedcounterme
asures

6. Transferring RPV head

RPV headWork
container B

Cutting tool

Illustrationof work
steps

Requiredfunctions: Scope of simulation in element tests

Avoiding of interfering objects during remote operation(Whether the cutting tool can be collected without interfering withinterfering objects around the fuel exchange bellows cover, etc.)

Installationof isolation
sheet B

➢
➢

①
②
③

②

Cable routing for equipment inside work container A①②

Verifying suitable placement of cameras through element tests
Studying the equipment configuration that would enable cablerouting inside the work container in accordance with upward
movement of the cutting tool/auxiliary arm①②③

Retreating of polar
crane disassembly
equipment, work
container A

It should be possible to safely transport the work container B up to the
opening after temporarily retracting work container A.
It should be possible to prevent outflow of radioactive materials from inside
the reactor and inside the work containers A, B into the cell.

➢➢

Measures against overturning of work containers A, B
Development of transportation technology that does not interfere with thegate between the cells
Ensuring air-tightness from inside of the reactor, inside of the work
containers A, B to outside the work containers A, B①②

The measures against overturning are being studied using largetransportation equipment.
The transportation technology is being studied using large transportationequipment.
Ensuring air-tightness by means of the isolation sheet is being studied
under another subsidy project.

①

➢

③

②
③

It should be possible to transfer the unitized RPV head.
It should be possible to safely transport the work container B up to
the additional building.
It should be possible to prevent outflow of radioactive materials
from inside the reactor and inside work container B to the outsideof work container B.

Measures against overturning of work container B
Development of transportation technology that does not interferewith the gate between the cells
Ensuring air-tightness from inside of the reactor, inside of the work
container B to outside the work container B

The measures against overturning are being studied using largetransportation equipment.
The transportation technology is being studied using largetransportation equipment.
Ensuring air-tightness by means of the isolation sheet is being
studied under another subsidy project (Isolation Technology PJ).

©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 (b) Other than reactor internal structures

No.342[RPV head bolt cutting test: Details of the preliminary tests and element tests]
The items that need to be verified by preliminary tests and element tests, and the framework required for verifying those items are consolidated in
the table below.
In the preliminary tests, basic (unit) tests on AWJ/equipment are conducted, and the element tests are conducted in bright light/in the dark.

◆Contents being explained

Preliminary test

Test details
AWJ basic test
AWJ performanceverification

Selecting AWJ processing conditions〇

Verifying whether or not cutting is possible (Verifying the impact on other structures)〇

Verifying the impact of axial tension during cutting〇

Element test

Basic equipment
test

In bright light

In the dark

〇 (No. 354)

〇 (No. 354)〇(No.361)

Collection
performanceverification

Verifying whether abrasive can be collected

Equipment
performanceverification

Verifying basic operation of equipment〇〇 (Prior verification
completed)〇 (Prior verification
completed)

Verifying the installation of equipment, and cable hose routing performance〇〇(No.352-355)〇(No.352-355)

Verifying emergency collection performance〇〇

Remote equipment
verification

Verifying placement of cameras/lights and installing them remotely

Combination test

One through test (Measurement of time for each work)〇(No.355)〇(No.358)〇(No.352-355)

Low pressure water jetting(tap water pressure)

Jet flow cover

AWJ
nozzleHighpressurewater jetting
location〇(No.352-355)

補助アームユニット
Auxiliary
arm unit

Low pressure water
jetting angle
Stud bolt〇(No.358)

Cutting
unit
切断ユニットポーラークレーン
Polar
crane

Flow of water

Water container
旋回ケーブルベア
Rotating
cable bear
Low pressure water jetting (tap water pressure)

Illustration of AWJ cutting

Illustration of AWJ cutting and abrasive collection

試験架台
Test
rack

Illustration of equipment for element test
©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 (b) Other than reactor internal structures[RPV head bolt cutting test: Illustration of the element test equipment]

No.343The images of the equipment used in the element tests based on the results of the study on the overview of theequipment, the reactor bottom retrieval steps, and the required functions, are given below.

Auxiliary arm unit

Winding drum
Cutting unit

Housing frame

Motor operated
winch

Traverse baseWinding drum

Test rack

Auxiliary arm

Cutting tool

Rotating cable bear

AWJ nozzle
Big-picture view of the RPV disassembly equipment (Polar crane) Detailed drawing of the cutting unit

Detailed drawing of auxiliary arm unit

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of retrieving large
No.344structures]① Method of cutting large structures (b) Other than reactor internal structures
Connection with the utility bymeans of the remote controlled
equipment inside thepassageway[Element test: Test equipment (RPV disassembly equipment (Polar crane))]Cutting unit

Auxiliary arm unit

Cable bear
Traverse rail

Rotation

Traverse table

8383

Rotating rail

Connecting
part

Traversing (moving sideways)

Illustration of actual equipment (inside the container)(The work container is not simulated, but the equipment isconfigured considering cable routing inside the work
container)

φ12570
Rotating cable bear

Test rack

Traverse cable bear

Items

Specifications

Equipment dimensions[mm]

Φ12570×H8383
Test rack
Rotating cable bear

RPV disassembly equipment

Requirements and remarks
Tactical diameter: Φ10300mm

Range of movement: ±180°

Cable can be routed inside the work container

Polar craneLoad to be lifted: 2960kg Acceptable maximum load of girder: 9000kg
traverse movement: ±3500mm

Cutting unit

Mentioned later in No. 345

Auxiliary arm unit

Mentioned later in No. 347

Use

Cutting the bolts-

Equipment weight (kg)

25900

-

Driving source

Motor operated-

Composition

Scope of©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 (b) Other than reactor internal structures[Element test: Test equipment (Cutting unit)]

Clamp unit

Scope of movement of eachaxis
Up and down movement: 10m
X axis ST*：160mm
Y axis ST：35mm
Z axis ST：130mm
Clamp mechanism ST：20mm
Guard opening and closing ST：75mm

Winding drum

Housingframe

Motor operated
chain pulley block

AWJ nozzle

Up and down
movementby means of
the chainpulley block

Cutting tool
cover

*ST: Stroke＋Z

EnlargedY

Cutting tool

Backward

Enlarged

Forward－ ＋

Seating frameX

Low pressure water nozzle－

Cutting tool near the nozzle

Cutting tool

Cutting unit
Items

Specifications

Equipment dimensions [mm]L2608×W1505×H4133

Cutting tool dimensions: L125×W1134×H1900

Winding drum

Cables of the cutting tool can be wound and fed

Composition

No.345Motor operated chain pulleyblock
Housing frame

Requirements and remarks

The cutting tools can be raised and lowered
Houses the cutting tool

Cutting tool

Can cut the bolts by means of high pressure water / abrasive jetting

Use

Cutting the bolts

Jetting of high pressure water and abrasive from the AWJ nozzle

Equipment weight (kg)2350

Driving source

Motor operated

Cutting tool weight: 350kg©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 (b) Other than reactor internal structures

No.346[Element test: Method of verifying cutting]・ When the actual equipment is assumed, cutting of the bolts needs to be verified remotely.
・ When an attempt was made to verify the status of bolt cutting by means of preliminary tests using only
cameras and LED lights, the simulated bolts could not be recognized visually. However, when a line laser
was used, the bolts could be visually recognized.
・ Similarly in the case of element tests as well, a line laser is used in the gap with the flange sheet, and thestatus of bolt cutting are verified by means of the camera ancillary to the cutting tool.
Simulated stud bolts could not be verified

Cutting tool

Cutting tool

Cutting tool
Simulated bolts

Only with camera LED lights

View from camera

State of verifying the simulated bolts (after they are cut)by means of cameras during the preliminary tests

Line laser
irradiationarea

Simulated bolts

Simulated stud bolts

Cutting surface
View from camera
Enlarged

AWJ nozzle

AA

Traces of cutting the simulated flange sealLine laser＋
CameraCameraLine laser

Only line laser

A-A cross-section

CameraStructure around the cutting tool nozzle

Line laser irradiation image

State of irradiating the line laser on the simulatedbolts (after they are cut) during the preliminary tests©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 (b) Other than reactor internal structures

No.347

Auxiliary arm[Element test: Test equipment (Auxiliary arm)]

The auxiliary arm
assists in monitoring
the cutting unit bymeans of cameras
and positioning it

Extension
Winding drum

Rotation -Auxiliary arm

Rotation +Cutting tool

Enlarged
Traversing base

Movementof the arm

State of assisting in positioning the cutting equipment

Auxiliary arm unit
Items

Specifications

Equipment dimensions [mm]L2700×W2600×H10235(H14735 when extended fully)

Composition

Requirements and Remarks
Auxiliary arm extension: 0 to 4500mm

Auxiliary arm

Payload 80kg (Maximum 150kg)

Winding drum

Drum diameter: Φ350mm Number of windings: Approx. 4.5
3min-1

Traversing base-Rotating speed: Maximum

Use

Assisting in positioning the cutting
tool

Holds the cutting tool and assists in positioning it on the RPV flange surface

Equipment weight (kg)3950 (Except the traversing base)

Auxiliary arm: 2500kg Winding drum: 1450kg

Driving source

Motor operated and hydraulic-©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 (b) Other than reactor internal structures

No.348[Element test: Camera installation]
Placement of cameras for remote monitoring during theelement test is given below.
Monitoring target of each camera

Installation
location⑩⑦

Cutting tool⑥⑨⑧
Auxiliary arm①⑤

On the traversing
trolley②③Big-picture view of the equipment/device

Cutting tool④
Auxiliaryarm

Bird's eye view
(Assuming acamera inside thework container)

CameraCameraspecifications

Use

①

Fixed

Assumed to be used forthe actual equipment

・Clamp part

②

Fixed

Assumed to be used forthe actual equipment

・Nozzle position and cutting completion

③

Fixed

Assumed to be used forthe actual equipment

・Nozzle position and cutting completion

④

Fixed

Assumed to be used forthe actual equipment

・Hand and cutting tool

⑤

Fixed

Assumed to be used forthe actual equipment

・Manipulator

⑥

Fixed

Assumed to be used forthe actual equipment

・Expansion pipe

⑦

PTZ*

Assumed to be used forthe actual equipment

・Cable hose drum⑧

PTZ

Assumed to be used forthe actual equipment

・Cutting tool and auxiliary arm⑨

PTZ

Assumed to be used forthe actual equipment

・Cutting tool storage and cable hose⑩

PTZ

Assumed to be used forthe actual equipment

Monitoring target

・Overall and polar crane*PTZ： Pan tilt zoom©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 (b) Other than reactor internal structures

No.349[Element test: Items to be verified]
The items to be verified by element tests, and their verification method are consolidated in the table below.
Work step

Items to be verified

Verification method

Equipment
manufacturing① Issues when manufacturing equipment① Identification of issues when large equipment are manufactured

Equipment installation(Manual work)① Issues at the time of equipment installation② Issues at the time of laying cables③ Work area image① Manual verification of installation work
(Identification of issues at the time of remote operation, if theactual site has been considered)② Manual verification of installation work (Identification of issues if theactual site has been considered)③ Manual verification of installation work (Recording of the area used
for work)

Element test

Common① Camera installation② Cable routing① Implementation of test with placement of cameras anticipating
actual equipment② Visual verification of the movement of cables with the help ofcamerasEquipment
insertion① Being able to align the cutting tool (flat)② Being able to lower the cutting tool / auxiliary arm while avoiding
interfering objects① Visual verification with the help of cameras② Visual verification of interfering objects with cameras, avoiding of
the interfering objects during polar crane operation

Cutting tool
positioning① Being able to align the cutting tool (height)② Being able to remotely clamp the cutting tool③ Being able to adjust the cutting position of the AWJ nozzle① Visual verification with the help of cameras② Visual verification of the clamped state with the help of cameras③ Visual verification with the help of cameras

AWJ cutting

①
②
③
④
⑤

Being able to cut the bolts
The cutting tool not moving while the bolts are cut
Cable hose not getting ripped
Being able to collect abrasive
Being able to verify that cutting has been completed① Cutting the bolts under cutting conditions verified by preliminary
tests② Verifying the images from the cameras③ Visually verifying with the help of cameras④ Verifying the amount of abrasive collected⑤ Visually verifying with the help of cameras and lifting up

Equipment
retrieval① Being able to release the clamp on the cutting tool② Being able to retrieve the cutting tool / auxiliary arm① Visually verifying with the help of cameras② Visually verifying interfering objects with cameras, avoiding theinterfering objects during polar crane operation©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]
Cutting tool
① Method of cutting large structures (b) Other than reactor internal structures[Element test: Test results]⑩ Camera images

Test equipment and stud bolts to be cut during theelement tests are indicated.
3 test pieces [Target bolt (D)]No.350

Auxiliary arm

Polar crane

5 test pieces [Target bolt (A, B, C
from below)]

RPV headStud bolt
Test piece
Test equipment (Bright light: Sufficient brightness is
ensured by means of the equipment lights)
180°

0°

⑩ Camera images

Polar crane

14.25°

Stud bolt test piece
Bolt
ID.

3 test pieces [Target bolt (E)]

Test equipment (Starting point)

Use details

A

Trial test

B

Trial test

C

Element test (in the
dark)

D

Trial test

E

Element test (in bright
light): Scope of the report

Light intensity inside thepit (measured value)
0.07[lx]
Blackout curtain
Test equipment (In the dark: Only equipment lights)©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing theconcept of retrieving large structures]

No.351① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]
The AWJ jetting conditions and scope of operation of the AWJ nozzle at the time of cutting during the element tests are indicated.
Nozzle delivery, etc. at the time of cutting was set based on the results of preliminary tests.
AWJ jetting conditions
Item

Condition

Ultra high pressure
water pump

AJP-35050G2(SUGINO)

Pumping pressure

350MPaFlow rate

4.8L/minAbrasive

Garnet #80

Abrasive feed rate

600g/minNozzle size

Φ1.2mmStand-off

80mm

Nozzle movement
speed(Optimum value basedon the fundamental
test)

Onward: 12mm/min
Return: 10mm/min

Automatic operation pattern
Instruction No.

X axis target [mm]Speed [mm/min]

1. Initial position

-72

12

2. Target value for “Onward”
cutting movement

+72

12

3. Target value for “Return”
cutting movement

-72

10

140 (Stud bolt diameter)

72
-72

72

+72
0 (Initial position)

Illustration indicating the scope of operation of AWJ nozzle during cutting©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing the concept
No.352of retrieving large structures]① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]
Results of element tests are indicated for each step.
1. Equipment insertion
Item
In bright light

In the dark

⑩ Camera image⑪ Camera image for the record

Polar crane

Cutting tool

State of the test

Cutting tool

Polar crane positioning⑪ Camera image for the record

Auxiliary arm

Lowering the cutting tool

Auxiliary arm

Cutting tool
⑪ Camera image for the record⑪ Camera image for the record

Lowering the cutting tool

Lowering the auxiliary arm

Lowering the auxiliary arm

Time

9[min]

8[min]

Results

It was confirmed that the polar crane can be positioned at the setting values: Rotation: -83.7[°] /Traversing: +2485[mm] as indicated in the drawing by remote operation, and the cutting tool andauxiliary arm can be lowered on to the target stud bolt without any interference. It was also
confirmed that the cable hose can be fed by means of the drum rotation interlinked with lowering.

It was confirmed that the polar crane can be positioned at the setting value: Rotation: +151.6[°] /Traversing: +2485[mm] as indicated in the drawing by remote operation, and the cutting tool and auxiliaryarm can be lowered on to the target stud bolt without any interference. It was also confirmed that thecable hose can be fed by means of the drum rotation interlinked with lowering.

Remarks

Polar crane positioning was carried out in a bright environment from the viewpoint of convenience related
to equipment.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing theconcept of retrieving large structures]

No.353① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]
Results of element tests are indicated for each step.
2. Positioning of cutting tool
Item
In bright light

In the dark

④ Camera image④ Camera image

Cutting tool

Auxiliary arm
Cutting tool

Cutting tool

Cutting tool

State of the test

Auxiliary arm⑪ Camera image for the record

Illustration from hand-held camera

Positioning of cutting tool

Clamping the cutting tool

Positioning of cutting tool

Test piece

Clamping of cutting tool

Test piece
Cutting tool

Cutting tool

④ Camera image

Photo taken from hand-held camera

Seating the cutting tool

Seating the cutting toolTime

8[min]

14[min]Results

It was confirmed that the cutting tool can be lowered remotely while pressing against the RPV flange
surface, under surveillance by means of the camera on the auxiliary arm, its seating can be
determined with the seating sensor and camera image, and it can be clamped.

It was confirmed that the cutting tool can be lowered remotely while pressing against the RPV flange
surface, under surveillance by means of the camera on the auxiliary arm, its seating can be determinedwith the seating sensor and camera image, and it can be clamped.

Remarks©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing the concept
No.354of retrieving large structures]① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]
Results of element tests are indicated for each step.
3. AWJ cutting
Item
In bright light

In the dark

Photo taken from hand-held camera⑪ Camera image for the record

Cutting tool

Cutting tool

State of the test

Photo taken from hand-held camera

AWJ cutting
Stud bolt

Bolt after cutting③ Camera image③ Camera image

Stud bolt

AWJ cutting③ Camera image③ Camera image

Stud bolt
Stud bolt② Camera image

Adjustment of nozzle position② Camera image

Verification after cutting② Camera image② Camera image

Adjustment of nozzle position

Verification after cuttingTime

49[min]38[min]Results

It was confirmed that the nozzle position can be adjusted by remote operation by determining thatthe nozzle has entered the 6[mm] gap with the flange where the laser is positioned, based on thecamera image.
It was also confirmed that completion of cutting can be determined from the camera image bymeans of the laser and low pressure water spray.
It was confirmed that there was no shifting, vibrations, etc. by monitoring the state of the cutting tool
during cutting with the camera on the auxiliary arm.

It was confirmed that the nozzle position can be adjusted by remote operation by determining that thenozzle has entered the 6[mm] gap with the flange where the laser is positioned, based on the camera
image.
It was also confirmed that completion of cutting can be determined from the camera image by means of
the laser and low pressure water spray.
It was confirmed that there was no shifting, vibrations, etc. by monitoring the state of the cutting tool
during cutting with the camera on the auxiliary arm.

Remarks

Time required for AWJ cutting only: 26[min]Time required for AWJ cutting only: 26[min]©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing the concept
No.355of retrieving large structures]① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]
Results of element tests are indicated for each step.
4. Equipment retrieval
Item
In bright light

In the dark
⑪ Camera image for the record⑪ Camera image for the record

State of the test

Cutting tools

Cutting tool

⑪ Camera image for the record

Auxiliary arm

Raising the cutting tool

Raising the cutting tool

Auxiliary arm⑪ Camera image for the record

Raising the auxiliary arm

Raising the auxiliary arm

Time

16[min]13[min]Results

It was confirmed that the cutting tool clamp can be released and the cutting tool and auxiliary arm can be raised
without any interference, by remote operation.
There were concerns that the cable hose would get caught in the housing part of the cutting tool, however, it was
confirmed that this can be avoided by remote operation by monitoring with the cameras.
It was confirmed that the cable hose can be wound by means of the drum rotation that is interlinked with the raising.

It was confirmed that the cutting tool clamp can be released and the cutting tool and auxiliary arm can be raised without
any interference, by remote operation.
There were concerns that the cable hose would get caught in the housing part of the cutting tool, however, it was
confirmed that this can be avoided by remote operation by monitoring with the cameras.
It was confirmed that the cable hose can be wound by means of the drum rotation that is interlinked with the raising.
(The time required for the polar crane to return to the starting point in bright light is considered from the viewpoint of
convenience related to the equipment.)

Remarks

It was confirmed that emergency retrieval of the equipment is possible, as long as the equipment has not failed, in 2
cases namely, ① When the X axis and Y axis of the cutting tool are still in the cutting position and ② When the motor
operated mechanisms are not in operation.

©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing the concept
No.356of retrieving large structures]① Method of cutting large structures (b) Other than reactor internal structures*： Has been calculated based on the time required for a series of operations
during the element tests. The time required for maintenance, etc. in the case of
actual equipment is not included.

[Element tests: Test results]
Results of the element tests conducted in bright light are summarized.

No.

Test item

1

Equipment
insertion

2

3

4

Positioning of
cuttingequipment

AWJ cutting

Equipment
retrieval

Result
Good

Good

Good

Good

Volume of abrasive supplied: 0.6kg/min

Time required(Element test: 1 unit)

Assumed time required*(Converted for actual Fukushima Daiichi NPS-4：76
units)

Assumed volume of waste(Converted for actual Fukushima
Daiichi NPS-4：76 units)

Total work time: 9min

Total work time: 684min

Total volume of waste: 0kg① Positioning of polar crane: 3min

① Positioning of polar crane：3min×76units =228min

No waste② Lowering of cutting tool：2min② Lowering of cutting tool： 2min×76units =152min

No waste③ Lowering of auxiliary arm: 4min

③ Lowering of auxiliary arm: 4min×76units=304min

No waste

Total work time: 8min

Total work time: 608min

Total volume of waste: 0kg① Positioning of cutting tool：3min① Positioning of cutting tool：3min×76units=228min

No waste② Seating of cutting tool: 4min

② Seating of cutting tool: 4min×76units=304min

No waste③ Clamping the cutting tool: 1min

③ Clamping the cutting tool: 1min×76units=76min

No waste

Total work time: 49min

Total work time: 3,724min

Total volume of waste: 1,186kg① Adjusting the nozzle position：13min① Adjusting the nozzle position： 13min×76units=988min

No waste② Preparing for AWJ cutting: 7min

② Preparing for AWJ cutting: 7min×76units=532min

No waste③ AWJ cutting: 26min③ AWJ cutting: 26min×76units=1,976min

1,976min×0.6kg=1,186kg④ Verifying after cutting: 3min

④ Verifying after cutting: 3min×76units=228min

No waste

Total work time: 16min

Total work time: 991min

Total volume of waste: 0kg① Raising the cutting tool：9min① Raising the cutting tool: 9min×76units=684min

No waste② Raising the auxiliary arm: 4min

② Raising the auxiliary arm: 4min×76units=304min

No waste③ Returning of polar crane to starting point：
3min③ Returning of polar crane to starting point:
3min×1unit=3min

No wasteIt was confirmed that a series of operations in bright light can be performed remotely with the cameras used this time.
©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing theconcept of retrieving large structures]

No.357① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]*: Has been calculated based on the time required for a series ofoperations during the element tests. The time required formaintenance, etc. in the case of actual equipment is not included.

Results of the element tests conducted in the dark are summarized.

No.

Test item

1

Equipment
insertion

2

3

4

Positioning
the cuttingtool

AWJ cutting

Equipment
retrieval

Results

Good

Good

Good

Good

Volume of abrasive supplied: 0.6kg/min

Time required(Element test: 1 unit)

Assumed time required*(Converted for actual Fukushima Daiichi NPS-4：
76units)

Assumed volume of waste(Converted for actual
Fukushima Daiichi NPS-4：
76units)

Total work time: 8min

Total work time: 608min

Total volume of waste: 0kg① Positioning of polar crane: 4min

① Positioning of polar crane: 4min×76units=304min

No waste② Lowering of cutting tool: 1min

② Lowering of cutting tool: 1min×76units=76min

No waste③ Lowering of auxiliary arm: 3min

③ Lowering of auxiliary arm: 3min×76units=228min

No waste

Total work time: 14min

Total work time: 1,064min

Total volume of waste: 0kg① Positioning of cutting tool: 6min

① Positioning of cutting tool: 6min×76units=456min

No waste② Seating of cutting tool: 1min

② Seating of cutting tool: 1min×76units=76min

No waste③ Clamping of cutting tool: 7min

③ Clamping of cutting tool: 7min×76units=532min

No waste

Total work time: 38min

Total work time: 2,888min

Total volume of waste: 1,186kg① Adjusting the nozzle position: 4min

① Adjusting the nozzle position:4min×76units=304min

No waste② Preparing for AWJ cutting: 5min

② Preparing for AWJ cutting: 5min×76units=380min

No waste③ AWJ cutting: 26min③ AWJ cutting: 26min×76units=1,976min

1,976min×0.6kg=1,186kg④ Verifying after cutting: 3min

④ Verifying after cutting: 3min×76units=228min

No waste

Total work time: 13min

Total work time: 763min

Total volume of waste: 0kg① Raising the cutting tool: 8min

① Raising the cutting tool: 8min×76units=608min

No waste② Raising the auxiliary arm: 2min

② Raising the auxiliary arm: 2min×76units=152min

No waste③ Returning of polar crane to starting point:
3min③ Returning of polar crane to starting point:
3min×1units=3min

No wasteIt was confirmed that a series of operations in the dark can be performed remotely with the cameras used this time and with lights mounted on the equipment.
©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing the concept
No.358of retrieving large structures]
Element tests List of cameras① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]

Installatio
n location

The use applications of the camera and items to be monitored
are consolidated based on the element test results.
Cutting
tool

⑩

⑦

⑨

Cameraspecifications

LightsUse application①

Radiation
resistant/splash
proof (Fixed)

LED

Mounted on cutting tool
(anticipating actual equipment)②

Radiation
resistant/splash
proof (Fixed)

LED

Mounted on cutting tool (anticipating actual
equipment)(Cover is installed while cutting to protect thelens)

・ Nozzle position
・ Cutting site③

Radiation
resistant/splash
proof (Fixed)

LED

Mounted on cutting tool (anticipating actual
equipment)(Cover is installed while cutting to protect thelens)

・ Nozzle position
・ Cutting site④

Water proof(Fixed)Provided
separately⑤

Water proof(Fixed)Provided
separately

Mounted on auxiliary arm (anticipating actual
equipment)⑥

Water proof(Fixed)Provided
separately

Mounted on auxiliary arm (anticipating actual
equipment)⑦

Splash proof
(PTZ)

LED

Mounted on auxiliary arm unit (anticipating actual
equipment)⑧

Splash proof
(PTZ)

LED

Mounted on traversing trolley(anticipating actual equipment)

・ Long shot (from above)・ Cutting tool・ Auxiliary arm⑨

Splash proof
(PTZ)

LED

Mounted on cutting tool unit (anticipating actual
equipment)

・ Cutting tool housing part・ Cable hose⑩

PTZ
(Pan tilt zoom)－

Mounted inside the work container (anticipating
actual equipment)

・ Overall long shot・ Polar crane

⑪

PTZ

－

For test records

・ Overall long shot⑥⑧

Auxiliary
arm

⑪
①

⑤

②
③
Big picture view of equipment/device

ID

Cutting tool④

On thetraversing
trolley

Mounted on auxiliary arm (anticipating actual
equipment)・ Clamp part・ Auxiliary arm hand
・ Work of cutting tool・ Auxiliary arm

Auxiliary arm
Long shot

Items to be monitored

・ Long shot (from above)・ Expansion tube

・ Cable hose drum

It was confirmed with regards to operations performed in bright light and in the dark, that a series of operations can be performed using cameras ① to ⑩ that are cameras assumed
to be used in actual conditions by the operator performing remote operations.
(In the case of operations performed in the dark, while using camera ⑧ it was effective to illuminate the cutting tool and auxiliary arm from above, thereby making the movements ofthe equipment visible.
It was confirmed that in addition to the above-mentioned lights, by providing localized illumination by means of the equipment lights, a series of operations can be performed without
much change from when they are performed in bright light.)©International Research Institute for Nuclear DecommissioningImplementation Items of This Project [2) (1) Development of technology for realizing theconcept of retrieving large structures]① Method of cutting large structures (b) Other than reactor internal structures

Upper surface to be cut

No.359Lower surface to be cut[Element tests: Test results]
The results of cutting the bolts during the element tests are indicated below
Perforation

Perforation

Upper surface to be cut

Simulatedflange sheet
surface

Lower surface to be cut

State of surface to be cut during preliminary tests[Results of cutting]
It was confirmed that the stud bolt can be cut by means ofAWJ.
5 bolts were cut in all during the element test, and there was
no failure or performance degradation in the equipment on
the whole.

Simulated stud bolt

[Issues]
It was found that there was a perforation in the flange sheet
surface as shown in the figure on the left (penetration).
During the preliminary test, the conditions under which theflange sheet surface would not get perforated were identified
and the element test was conducted under those conditions,however, a slight perforation was found at the distal end of
the stud bolt.
Simulated bushing

Direction of
AWJ spray

Nozzle (Onward)
Nozzle (Return)This time cutting was performed by moving the nozzle backand forth in the radial direction, but measures in accordancewith the surface to be worked on such as reducing theprocessing time for the distal end where less cutting isrequired, and cutting the middle portion of the stud bolt that is
thick by means of back and forth movement, etc., and reviewof the AWJ spray conditions will be studied.

State of surface to be cut during element tests (Bolt D)©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing theconcept of retrieving large structures]

No.360① Method of cutting large structures (b) Other than reactor internal structures[Element tests: Test results]
The generation of secondary waste as a result of AWJ cutting will be controlled to the extent possible by following the policy given below.
・ Reducing the inflow of abrasive inside the RPV by making sure the flange sheet surface does not get perforated (Preventing the secondary waterfrom turning into fuel debris)
・ Capturing the water and abrasive returning towards the AWJ nozzle by means of a low pressure water jet, and collecting it to the extent possibleusing the cutting tool cover ⇒ Refer to the following pages
・ The water and abrasive that do not get collected using the cutting tool cover accumulate in the sealed portion of the alternative combustion bellows
and the basin seal skirt. A method of collecting these after cutting will be studied for application to the actual equipment.
RPV head bolt

Upper hemisphericaldome flange build-up
welding

Flange sheet surface

Upper hemisphericaldome flange

Low pressure water jet

Cutting tool cover

Low pressure
water jet angle
Jet flow coverCutting toolcover

AWJ nozzle

High pressure
WJ position

RPV flange build-up
welding

RPV flange

Alternative
combustion bellows

Basin seal skirt

Scraps, water,abrasive accumulate

Water tank

Low pressure water jet©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 (b) Other than reactor internal structures

No.361[Element test: Test results]
The rate of collection of abrasive verified during the element test is given below.
Low pressure water jet
Flow of water

Low pressure
water jet angle
Jet flow coverCutting tool cover

Collection of abrasive after cutting 1 stud bolt

High pressure
WJ position

The abrasive collected using the filter was dried and its
quantity was measured.

Water tank

Low pressure water jet

The abrasive was removed
by means of the lowpressure water jet between
the flange sheet surfaces,
and was collected in the
cutting tool coverConcept of abrasive collection
Quantity of abrasive supplied
0.6kg/minx

Time for which abrasive was supplied per stud bolt

AbrasivecollectingtankQuantity of abrasive collected per stud bolt
4.53kgQuantity of abrasive used in the element test
Rate of collection of abrasive per stud 4.53/15.6 x 100 = 29%

26min

Quantity of abrasive supplied per stud bolt
15.6kg

The specific gravity of AWJ is about 4. Typically the plan was to accumulate
the abrasive at the bottom of the abrasive collection tank, but after cutting
the bolt, the particle size of the abrasive reduced, due to which lot of it
started floating on water. Hence it is assumed that lot of abrasive overflowed
without accumulating at the bottom of the tank.

Design value of the quantity of abrasive supplied©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 (b) Other than reactor internal structures

No.362[Element test: Test results]
Verification results for each test item of the element test are given below.
Work step

Items to be verified

Result of verification

Equipment manufacturing①

Issues when manufacturing equipment①

Equipment installation(Manual work)① Issues at the time of equipment installation② Issues at the time of laying cables③ Illustration of work area①

Element test①②①

CommonCamera placement
Cable routing

There are issues related to connection (Refer to ID.1 on the next
slide)

There are issues related to the connecting parts (Refer to ID.2 on thenext slide)② None in particular③ Work area approx. 720m2: (Approx. 45×16m)(Simulated area inside the well: Approx. φ133m 2,
Including the ancillary equipment, operating area, truck yard, etc.)②

A series of operations are possible with cameras placed anticipating
the actual equipment.
There are no issues in moving the cables.

Equipment insertion① Being able to align the cutting tool (flat)② Being able to lower the cutting tool/auxiliary arm while avoiding
interfering objects.

① It was possible to align the cutting tool.
② It was possible to lower the cutting tool/auxiliary arm while avoiding
interfering objects.

Cutting tool
positioning①②③

Being able to align the cutting tool (height)
Being able to remotely clamp the cutting tool.
Being able to adjust the position of the cutting tool in accordancewith the cutting position of AWJ nozzle①②③

AWJ cutting

①
②
③
④
⑤

Being able to cut the bolt
The cutting tool not moving while the bolt is being cut
The cable hose not getting ripped
Being able to collect the abrasive
Being able to remotely verify that cutting has been completed① It was possible to cut the bolt.
② It was verified that the cutting tool does not move while the bolt isbeing cut.
③ The cable hose did not get ripped.
④ The rate of collection of abrasive was low. Hence the issue is pending.
⑤ It was possible to remotely verify that cutting has been completed.

Equipment retrieval①②

Being able to release the cutting tool clamp
Being able to retrieve the cutting tool/auxiliary arm①②

It was possible to align the cutting tool.
It was possible to remotely clamp the cutting tool.
It possible to adjust the position of the cutting tool in accordance withthe cutting position of AWJ nozzle.
(It was possible to set the center of the nozzle in the 6mm flangegap.)

It was possible to release the cutting tool clamp.
It was possible to retrieve the cutting tool/auxiliary arm.

©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 (b) Other than reactor internal structures

No.363[Element test: Test results]
The issues identified during the element test, and the action plan directed towards actual equipment are given below.
Measures undertaken
during the test

ID

Event

Cause

1

At the time of equipment installation, there was
misalignment of about several mm in the levelingblock fixing holes at several locations, in which thepolar crane is fixed, due to which the equipment
could not be installed into the facility. (There was noissue in the drawings.)

Since large equipment are connected in thefacility, it was inferred that this was due tomanufacturing error.

As an emergency
response, the fixing holeon the equipment side wasdrilled further and theequipment was installed.

The equipment will be designed to have some margin
considering manufacturing errors of large equipment,etc.

At the time of verifying operation, when the polar
crane was turned anti-clock-wise, there was a soundof scraping of metal.

There was a slight difference in level at theguide frame connecting part. When thepolar crane was being turned, theconnecting parts of the rotating cable bear
got misaligned and made a sound.

The guide frame was
repaired and it was
confirmed that the polar
crane can be turned
without any scraping.

・Inspection of all connecting parts before carrying-in
will be included in the procedures.
・The operation will be thoroughly verified before
carrying-in.

At the time of the trial test, when an attempt wasmade to raise the cutting tool, the cutting tool frame
got caught in the bushing stopper bolt and hence thecutting tool could not be raised.

The part that comes in contact with thestructures has been chamfered, but thechamfering was insufficient and hence thecutting tool frame could slip off.

Additional chamfering was
performed, and it was
confirmed that the frame
does not get caught any
more.

The amount of chamfering of the part that comes incontact with the structures will be taken into account
while designing.

At the time of the trial test, the cutting tool wasseated on the RPV flange, but the seating sensor did
not sense it.

As the sensitivity of the seating sensor wasincreased, it did not sense due to the impactof about 1mm manufacturing error in thetest piece.

The seating was confirmed
using a camera.

・The damage, tolerance of the actual equipment will
be taken into consideration while designing.
・A mechanical verification method will be considered.

An abrasive collection tank is mounted on the cutting
tool to prevent abrasive from getting deposited dueto the jet flow or flowing to the outside, but when therate of collection was actually measured, it was
about 29%.

It is inferred that flowing of the abrasive tothe outside could not be completely
prevented by the guard formed by the jet
flow.

－

Equipment configuration that would enable collectionof abrasive in real-time while preventing its outflow
will be studied.
The method of collecting the abrasive accumulatedon the sealed portion of the fuel exchange bellows
and the basin seal skirt, which is too much to becollected, will be studied.

During the preliminary test, cutting was performed
without perforating the flange sheet surface, but theflange sheet surface was found to have been
perforated after cutting.

Element test was conducted under thesame conditions as the preliminary test, but
it was inferred that the perforation was a
result of the difference in environment suchas the hardness of the material, etc.

－

This time the nozzle was moved forward andbackward, but measures pertaining to the operationsuch as starting to cut from the center of the stud bolt
where it is thick, etc. and review of the AWJ
conditions will be considered.

2

3

4

5

6

Action plan directed towards actual equipment©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 (b) Other than reactor internal structures

No.364[Status of equipment installation (Manual work)]
It is assumed that the equipment will be installed in its entirety at the actual site, but this time parts of the equipment were manually assembled and installed.
1. Installation of runway girder 1
Leveling block

Runway girder 1

2. Installation of runway girder 2 to 6

3. Installation of traveling rail

Runway girder 1

4. Installation of traversing crane girder
Traversing crane
girder

Step 2Illustration

Traveling rail (4 units)
Runway girder 3

Hook bolt (136 units)

Runway girder 1

Step 1

Enlarged view of hook bolts

Traversing crane girder

Status of installation work

Travelingrail

Status if installation of
runway girder
Status after installation of runway girder

Runway girder

Hole position on the levelingblock side

Status after installation of traveling rail

Installation of traversing crane girder

Verifying that there is no difference inlevel in the rail that was assembled inparts

Traversing crane girder

Fixing of bolts after
further drilling

Leveling block

Work
step

The runway girder was assembled in 6 parts.
Height was adjusted with the leveling block.
(Target: Difference in height of the girders:
2mm or less)Hole position on the
runway girder
The leveling block and the fixing hole on theequipment side were misaligned. The fixing
hole was drilled further and the equipment
was installed.

Traveling rail

The traveling rail was assembled in 4 parts.
The rail installation position was adjusted inaccordance with the guide line marking andthe rail was fixed.

A traversing crane girder was installed on
the traveling rail.

©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]

No.365① Method of cutting large structures (b) Other than reactor internal structures[Status of equipment installation (Manual work)]
5. Installation of traversing cart
Traversing cart

6. Installation of auxiliary arm,
cutting unit
Cutting unit

Auxiliary arm

7. Installation of rotating cablebear

8. Installation completion

Rotating cable bear

Illustration
Traversing cart

Auxiliary arm

Status of installation work

Traversing cart

Cutting unit

Rotating cablebear

Status of installation of
traversing cart
Traversing
cart

Traversing
crane
girderWork
step

The traversing cart was installed on
the rail of the traversing crane
girder.

Traversing
cart

The auxiliary arm, cutting unit were
installed on the traversing trolley.

External appearance after
completing the installation of thepolar craneStatus of installation ofrotating cable bear

The rotating cable bear was
installed around the runway girder.

Installation completion

As setting the levelness of the runway girder that forms the base is important, the method of installing the equipment needs to be studied anticipating application to the actual site.

©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 (b) Other than reactor internal structures
Usage of AWJ, etc.

[Illustration of improvement in abrasive collection]
・ Approx. 1.2ton abrasive is planned to be used if all 76 bolts in Unit 4 are to
be cut under the current cutting conditions.
・ With the current collection rate of 29%, 855kg of abrasive is likely to spread
inside the PCV or inside the RPV thus increasing secondary waste.
→ In order to reduce the quantity of secondary waste anticipating applicationto actual site, it is believed that equipment configuration that would enablereal-time collection of abrasive will need to be studied.

No.366

Items

Usage while
cutting 1 unit

Usage while
cutting 76
units

Duration of cutting

26.4 minutes

33.5 hours

Total quantity of water used

126.72L

9,631L

Quantity of abrasive supplied

15.84kg

1,204kg

Quantity of abrasive outside
the tank(71% of the quantity supplied
mentioned above)

11.25kg

855kg

The overflown water accumulates
inside the reactor well when the
structures are in sound condition.

Pump (Vacuum pump, etc.)

To the collection container

Flows inside the
RPV when the
sheet surface isperforated
Flange sheet surface
Fuel exchange
bellows

Scraps, water, abrasive
accumulate when the
structures are in soundconditions

Connecting the hose to the tank

Basin seal skirt

Flows into the PCV
when structures aredamagedIllustration of the area where abrasive spreads

AWJ nozzle

AbrasivecollectiontankIllustration of revisions to the equipment
configuration anticipating application to actual site
©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 (b) Other than reactor internal structures

No.367[RPV head bolt cutting step at the actual site]
Measures against impact of distortion of the RPV head at the actual site and issues to be studied in the future are given below.
There are concerns that due to the impact of distortion, as the cutting of the bolt progresses, the axial tension of the bolts that fix the RPV head
will gradually get released, and the RPV head will get deformed, due to which the flange gap of 6mm used for AWJ cutting will get blocked.
Therefore, the following physical and operational measures have been proposed.
Wedge (45°pitch at 8 location)

5 4 1

Fall prevention
wire

Bolt head
Fall prevention wire

Wedge

Wedge

Proposed physical distortion countermeasure (Illustration)
Wedges with fall prevention wire will be inserted in the circumferential direction at equal intervals forpreventing the flange gap from getting blocked due to RPV head distortion.
The fall prevention wire will be hooked on to the bolt head part and the wedge will be inserted with the helpof the work equipment such as the auxiliary arm.
Issues: Position and structure of the wedge such that the wedge does not interfere with the cutting tool
when the cutting is performed, and such that the wedge itself does not get cut, need to be studied.

2 3 6・・・

The numbers in the drawing
indicate cutting sequence.
Cutting is performed up to the76th bolt following the sameprocedures.

Proposed operational distortion countermeasure (Illustration)
Cutting will be performed diagonally so that axial tension remains uniform.
Issue: The work will require a longer time.
As a countermeasure, considering a few adjacent bolts as a block and moving diagonally foreach block need to be studied.
©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 (b) Reactor internal structures

No.368[Method of cutting reactor internal structures into large pieces: Development policy]
Element test on the filling and solidificationmaterial for the reactor internal structures below the
shroud will be implemented focusing on studying themethod of cutting structures into large pieces andthe concept of the equipment.

<Separator example> Method of cutting
1. Cutting the 2. Removing the
3. Rotating
off fastened parts assumed to beremaining part ofnut
the T bar
the nut
damaged and deformed
Shroud head bolt
Nut
Remaining
Separator

RPV head
Heat insulating
material
Dryer
Separator

ShroudStump-shaped
fuel
CR guide tube

CRD housing

Shroud headbolt

Shroud head

Pulling up the
separator

Upper shroud⚫ It may not be possible to loosen the
nut due to corrosion. Hence the nut
will be cut and removed, the shaft of
the T bar will be rotated to remove
the stopper.

Shroud headUpper shroud

Disassembling
equipment

part of thenut

To be cut

PCV head

4. Pulling up
the separator

Lug

Cutting
manipulator
Separator

T bar

Studies will be conducted on the method of cutting structures and theconcept of the equipment.

Example of the concept ofdisassembling equipment<Example of shroud> Fuel debris retrieval by means of filling and solidification forpreventing fuel debris from falling when unitized large structures are transported will be
studied.
Some of thefuel in the outer
peripheryremains

Fuel debris
deposited in thereactor core
ShroudCutting of entire
cross section

CRD platform
MCCI

Fuel debris
deposited at thereactor bottom

Estimatedcurrent status

Fall prevention by injecting filler
material

Cutting of reactor internal structures(Example of cutting with wire saw)

Studies will be conducted on the method of cutting structures and the concept of the equipment, and element tests
will be conducted related to the filling and solidification material for 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
retrieving large structures]① Method of cutting large structures (b) Reactor internal structures

No.369[Scope of application of filling and solidification]•
In order to prevent the structures in the reactor core and at the reactor bottom from falling, the structures inside the shroud will be filled andsolidified.
•
Whether or not filling needs to be performed at the actual site, and the scope of filling is planned to be determined by investigating the status
inside the reactor core.
•
In this project, the steps involved in this method and element tests will be studied focusing on Case A which includes working on heavy weight
objects.
A. Damage progression

Small scale

Conceptual drawing

Some of thefuel remains
in the reactor
core

Major part of
supportstructures
have
retained theirform

Fuel debris ispresent at
the reactor
bottomLittle has
flown to thepedestalFew
openings arepresent in thelowerhemisphericaldome

Filling andsolidification

Response•

B. Damage progression

Medium scale

Major part of
the fuel has
flown to thelowerhemispherical
dome

Many of the
supportstructures havemelted andhave gotten
damagedFuel debris ispresent at
the reactor
bottom
A lot hasflown to thepedestal

Many openings
are present in
the lower
hemisphericaldome

C. Damage progression

Large scale

Major part of
supportstructures
have melted
and flown out

Major partof the fuelhas flown
on to thepedestal

Structures in
the lower
hemisphericaldome havemelted andfallen on to thepedestal

Localized fillingand solidification

MeritsDemerits

・ Localized filling and solidification of the remaining fueldebris・ Reducing the scope to the part where fuel debris remains,
cutting large structures and transferring

・ Filling and solidification not required
・ Cutting into portions as large as can be transferred・ Transferring in large pieces (Small number of pieces)・ Small quantity of filling (Small quantity of secondary
waste)・ Reduction in weight of the objects to be transferred・ Reduction in abundance of fuel debris
・ Reduction in quantity of structures to be transferred・ Heavy weight of the objects to be transferred・ Large quantity of filling (Large quantity of secondary
waste)・ Reduction in cooling performance

・ Increase is number of pieces (Increase in amount of work
as well)・ Increase in handling of objects with indeterminate form
(Complication of work)

・ Increase in handling of objects with indeterminate form
(Complication of work)•

Filling and solidification of fuel debris inside the reactor
core and at the reactor bottom
Cutting and transferring as large structures©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]

No.370① Method of cutting large structures (b) Reactor internal structures[Method of cutting reactor internal structures into large pieces Study conditions]• Study conditions of the method of transferring unitized large structures are given below.
ID.

Study conditions

Basis

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
structures other than reactor internal structures such as
dryer and separator are already removed.

2

The outflow when geopolymer is filled inside theshroud is comparatively less. A condition wherein thegeopolymer continues to pile up is assumed.

First, as the viability, etc. of large scale filling will beverified, study will be conducted under the condition
wherein the filler material can be filled.
If the reactor bottom is significantly damaged and filling isdifficult, the method of localized filling around the fueldebris will be selected.

3

The cutting method will be studied under theconditions wherein filler material is filled inside theshroud 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 thejet pump will have already been removed and the tool will
have been set in the gap between the shroud and the
RPV inner surface

It was evaluated that the priority levelof the development for the jet pump
retrieval work is lower than the otherstructures.

5

The shroud, etc. must not be significantly tilted.

The conditions of the shroud is uncertain, but it was
tentatively installed for the study.
A configuration that would make it possible to modify themethod of fixing the tools depending on the actual site
conditions will be studied.

Results of the estimation of shroud
condition carried out during theUnderstanding the Status Inside theReactor Core PJ
Unit 1: Likely to have been damaged
Unit 2: It is assumed that there is nolarge scale damage
Unit 3: Likelihood of being sound andlikelihood of being damaged,
both are conceivable.

©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 (b) Reactor internal structures

No.371[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 filler
material were studied.
As multiple structures (materials) need to be cut, it was assumed that the bulk cutting method indicated in Cutting
Example 1 has a higher level of technical difficulty, and hence the cutting tool was selected considering the method of
cutting in parts indicated in Cutting Example 2 as the main proposed method.
① Structure: ・ 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
Example 1:
Bulk cutting

Jet pump has
been removed
in advance

Lower portionof shroud

Illustration of steps
involved in cutting

Fillermaterial

Area that has
been cut

Shift incutting
location

Cutting
location

CutterLower portionof shroudCR guide tube
Filling andsolidification

Cutting position (Cutting the fuel debris, filler material, CR
guide tube)(Illustration of cutting of the shroud and filler material
horizontally in bulk with a wire saw, etc.)

CR guide tube

Fuel debris +filler material

Cross section of cutting location(Conceptual drawing)＊ The cutting characteristics ofthe metal plate, filler material andthe ceramic material are different.

Cutting location

Cutting
Example 2:
Cutting inparts
Shift incutting
location

Lower portionof shroud
Cutting the outer periphery of the shroud(The metal plate is cut first.)

Cutting the remaining filler
material / ceramic material©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]

No.372① Method of cutting large structures (b) Reactor internal structures[Method of cutting reactor internal structures into large pieces Study on the course of cutting]•

It was decided to carry out development related to the method of cutting the outer periphery of the shroud for the method of
cutting in parts, on a priority basis.
Study conditions

Cutting the outer periphery of the shroud

Cutting the remaining filler material / ceramicmaterial

CutterIllustration of cutting

Cutting location

Shift in cutting
location

Lower portion of
shroudSteps involved in
cutting

The metal plate will be cut first.

Filler material, reactor internal structures including
fuel debris will be cut.

Portion to be cut

Outer periphery: Sheet thickness approx. 38mm,
Material Stainless steel

Interior: Inner diameter approx. 4.4m, Material
Filler material + CR guide tube (SUS) + Fueldebris (ceramic material)

Cutting method

AWJ, laser, etc.

Wire saw, etc.

Development policy

Will be studied in this subsidy projectWill be studied in the future upon verifying thestatus after cutting the outer periphery of the
shroud during this subsidy project©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.373
retrieving large structures]◎: High applicability○: There are prospects of application① Method of cutting large structures (b) Reactor internal structures△: Countermeasures are required[Method of cutting reactor internal structures into large pieces Selection of cutting method]
The cutting tools applicable to cutting the outer periphery of the shroud will be evaluated, and an appropriate cutting method will be selected.
Evaluation items

Cutting performance
Dross removal

Accessibility(Small head)Controlling
generation of
secondary waste

Compact utility

Prevention ofdust dispersion

◎

-

◎

△

△

△

△

〇

△

〇

〇

△

△

Laser + WJ

〇

〇

〇

〇

〇

△

△

Gas cutting

△

x

-

〇

〇

△

△

Plasma arc

△

〇

△

〇

〇

△

△

Machine cutting (Band saw,
circular saw, etc.)

△

△

-

△

〇

〇

〇

Wire saw

△

△

-

△

〇

△

〇

Fire
prevention

ShroudAWJ〇

Laser cutting

Cutting tool・ In the case of AWJ cutting, abrasive enters the reactor core which leads to an increase in secondary waste.
・ Gas cutting cannot be used as the shroud is made of stainless steel.
・ In the case of laser cutting and plasma arc cutting, removal of dross is an issue.
・ Cutting performance is an issue in the case of machine cutting.

The method of combining laser cutting and WJ cutting so that the dross in the molten metal generated during laser cutting can be removed,
has the best prospects as the cutting method.
(As laser cutting is performed while simultaneously removing dross by means of intermittent WJ spray, the heat input to parts other than thosethat are being cut reduces due to the cooling effect of WJ. And even if the fuel debris gets exposed to laser and gets cut, the risk of criticality
is assumed to be low.)©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 (b) Reactor internal structures

No.374[Method of cutting reactor internal structures into large pieces Study of the cutting method]••

The results of conceptual study of the equipment for cutting the shroud with laser and WJ are given below.
The method of installing a rotating base on the upper portion of the shroud, inserting the cutting tool into thegap between the RPV and the shroud, and cutting the shroud from the outside by means of laser and WJ with
1 rotation, was studied.
Cutting is performed byirradiating the laser beam
and at the same timeintermittently spraying WJ in
the oblique direction toremove the dross in themolten metal.

Rotatingbase

WJ (intermittent
spray)

Laser+ WJ
nozzleLaser+ WJ
nozzleCutting
Laser

Cutting is
performed byfeeding the laser
along the side of
the shroud

Illustration of the cutting equipment for reactor internal structures (shroud)

Illustration of cutting by means of laser + WJ
©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 (b) Reactor internal structures[Method for cutting reactor internal structures•

No.375

Element test plan (Status of progress)]

Verification of the viability of whether or not the shroud can be cut by means of laser + WJ
through element tests by test manufacturing focusing on the laser + WJ head, is being studied.

Rotating
base
XYZ
Actuator
Laser+ WJ
nozzleCutting

Simulated
flat plate

Tank
Laser + WJ
head

Illustration of actual equipment

Illustration of the element test
©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 (b) Reactor internal structures

No.376[Filling and solidification material development policy]⚫
⚫

Based on the results of past studies, issues that became evident through past studies and items that are yet to be studied, which are mentioned in thetable below, are being studied.
As 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 and solidifications taking the actual equipment into consideration, the characterization
tests mentioned in ID. 4 are being implemented.
IssuesStudy related tomaintaining the function of
the filled and solidified
units

Study of filling filler
material inside the RPV
anticipating the actual
equipment

Evaluation of impact offilling

Implementedin (year)ID.

Study items

Details1

Evaluation of the impact on solidification
function assuming environmental condition
inside RPV

Upon evaluating the temperature assumed inside RPV, its
impact on the solidification function will be evaluated (Timerequired for solidification, change in strength, etc. underhigh temperatures will be verified).

FY20212

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 will be verified.

FY20213

Study of filling filler material inside thereactor

The method by which filler material ought to be injected into
RPV (how it ought to be filled at the point of injection andthereafter) will be studied.

FY2021

4

Characterization through injection test
conducted using a barrel

Characterization of geopolymer (verifying whether or not it
can be filled, its strength, etc.) will be carried out throughan injection test conducted on a scale larger than theprevious basic test, by using a barrel.

FY20215

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 will be studied.

FY2022

6

Study of the filling procedures and methods
anticipating filling at the actual site

The type of equipment required will be studied considering
the results of the studies in ID.3 and ID.4.

FY20227

Impact on treatment and disposal

The impact on treatment and disposal of the filled andsolidified units will be studied.

ーThe observations of cross sections of the solidified units, etc. are being evaluated and the results are being consolidated.
©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 (b) Reactor internal structures

No.377[Overview of characterization test]⚫ The test conditions and the image illustrating the verification tests (barrel injection test) for
characterization are given below.
ID.

Items

Conditions

Remarks1

Number of tests

Once at room temperature andonce by heating at 80℃

2

Barrel heating temperature

Assumed to be 80℃

Assuming that heat will be generated by fuel debris, the bottom part will be heated.

3

Water level

100mm

・ Although details are not yet verified, it is assumed that the water level inside RPV is not as high.
・ Current sub-criticality is taken into consideration

4

Temperature measurement
position

Measured at the bottom,
175mm, 350mm, 525mm +water surface

・ About 80% (700mm) geopolymer will be injected in a 200L barrel of height 900mm.
・ The internal temperature at the time of geopolymer solidification will be monitored at the bottom, andat 1/4, 2/4, 3/4 the height of the barrel.
・ The temperature of water will be measured by floating a thermocouple on the surface of water using afloating tube.

5

Temperature of the basic
ingredient of geopolymer

Cooled to 10℃ or less

Each basic ingredient will be cooled to 10℃ or less, and will be mixed at room temperature.

6

Geopolymer injection speed

Natural course (about 30 min)

The reduction in weight of the barrel on the supply side will be measured with a weight scale and theinjection speed will be calculated from the time required and the change in weight.

Weight scale

Thermocouple

Geopolymer
Water

Mortarpump
Barrel[Evaluation items (planned)]
・ Verification of the condition after filling andsolidification(The solidified unit will be cut into half and thecross section will be observed)
・ Strength evaluation, component analysis(Whether or not core boring can be performed isbeing coordinated.)

Heater©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.378: Planned: Planned (after revision)*◼ Development Process: Actual

FY2021

FY2022

Study items
4
Major milestones

5

6

7

8

9

10

11

12

1

2

3

Interim Report▼

45Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

12

1

2

3

Final
report
▼1. Conceptual study

2. Element test planning

3. Test preparation/
Test manufacturing oftest equipment
4-1. Element tests(Cutting of RPV headbolt)(Moved up from the original plan of
October 2022 onwards)

4-2. Element tests(Cutting of reactor
internal structures)

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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: Summary

No.379➢ Pre-conditions pertaining to the method of transferring unitized large structures
have been consolidated.
➢ Conceptual study was conducted on the method of disassembling the RPV head,
method of filling and solidification of the reactor core, etc. and the method of
cutting reactor internal structures.

➢ The element test plan related to cutting of RPV head bolts was created. 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 themethod of cutting the RPV head bolts was verified, and issues are being
consolidated.
➢ Element test plan for cutting the reactor internal structures is being created. In the
future, the feasibility of the method of cutting of reactor internal structures will beverified by element tests.

©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]

No.380

Solicitation items are listed② 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 thelarge transfer 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 by 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
retrieving large structures]② Large transfer containers

No.381[Status of studies up to FY2020]⚫ Conceptual study on the large transfer containers was conducted.
⚫ The element tests related to air-tightness of the lid part of large transfer container were conducted during the
Ensuring Safety PJ.
Movable flange

Upper lid

← Developed during theLower lid Ensuring Safety PJ

Large transfer
container← To be developed
during this PJ⇒ The structure of the main body of the large transfer container will be substantiated and the viability of thestructure 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.382
retrieving large structures][Notes]Colors indicate the following contamination levels*
R: Red (high contamination) zone
② Large transfer containers
Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone

*Besides color, the main zones are marked as R, Y and G.
[Issues]•
In order to transfer unitized large structures, large transfer containers with a function for preventing the spread ofcontamination need to be developed.
•
Study on the confinement performance including when the large transfer container is opened and closed, andverification of feasibility•
Study on manufacturing capability including processing and assembly, and verification of feasibility•
Method of remotely connecting the large transfer container and the lid, etc., handling property

Shielding cart

[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 element tests, feasibility evaluationand issues.

Transportation cart

YWork
container

R

R

Container Large transfer container
dual lidG
Reference: Illustration of themain body of the container

Weight:Approx. 390t

Φ8m

Illustration of the container
Fuel debris at thereactor bottom

7.5m[Implementation details]• Preconditions related to the study will be consolidated.
• Studies will be conducted on establishment of the concept of thetransfer system including the method of storing into the large transfer
container and the detailed procedures for transferring the entire largetransfer container, based also on issues studied during the Ensuring
Safety PJ.
• Structural designing of the large transfer containers will be carriedout. Studies will be conducted considering decontamination of theinside of the container assuming that the transfer container will bereused.
• Element tests will be planned, the large transfer container will be test
manufactured, their feasibility will be verified and issues will beconsolidated.

Φ6m
Φ7m
Main dimensions

Illustration of collection at the reactor
bottomAdditional 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
retrieving large structures]② Large transfer containers

No.383[Implementation details]

Implementation items

Implementation details

Consolidation of preconditions

The preconditions while using large transfer container will be consolidated.

Study on large transfer
containers・Studies will be conducted on establishment of the concept of the transfer
system including the method of storing into the large transfer containers andthe detailed procedures for transferring the entire large transfer container,
based also on issues studied during a different subsidy project (Ensuring
Safety PJ).

Structural designing of thelarge transfer containers

・Structural designing of the large transfer containers will be carried out.
・Studies will be conducted considering decontamination of the inside of thecontainer assuming that the large transfer containers will be reused.

Element test planning andimplementation

・Element tests will be planned, the large transfer container will be test
manufactured, their feasibility will be verified and issues will be consolidated.
・The dual lid that was test manufactured during the Ensuring Safety PJ will be
combined with the large transfer container test manufactured during thisproject and tests will be conducted.

©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]② Large transfer containers

No.384[Preconditions]• Preconditions for the method of transferring unitized large structures are given below.
ID.

Preconditions

Basis

1

The structure of the container must enable storageof the structures cut into large pieces.
(The container must be able to store structures thatare about φ5.5m, H5.5m.)

The structure of the container must enable storageof units that have been cut and transferred forevery structure using the method of transferring
unitized large 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 to storage will be evaluated in futuresubsidy 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
would be 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
retrieving large structures]② Large transfer containers

No.385[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.

[Preconditions]

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 andstored in canisters and transport casks.
Scope of use of large transfer containers

Shielding cart Transportation cart

Newl building

Fine cutting cellYWork
container

R

R

Container
Large transfer container
dual lid

Receiving cell

Fine cutting

To the storage facility

Additional building

Canister Transport
caskG(A) Operations in the additional building[Details of the operations]・ The connecting parts of the structures will be cut, the structures will
be hoisted using a crane and unitized large structures will betransferred from the PCV.
・ After the structures are moved over the operation floor using thetransportation cart, they will be lowered with the help of the crane in
the additional building, stored in large transfer containers anddelivered.

(B) On-site transportation[Details of the operations]・ The structures stored in the largetransfer containers will betransported on site to the newbuilding.

(C) Operations in the new building[Details of the operations]・ The structures will be removed from the large transfer
containers.
・ The structures will be finely cut and stored in canisters
and transportation casks.
・ The transportation casks will be delivered and stored at
the storage facility.

©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]② Large transfer containers

No.386[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

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.

Approximate dimensions of thecontainers with common
specifications

Inner diameter Φ6000×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 formaintaining the boundaries through a series ofprocedures.

The sealed portion 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 inside thePCV (high contamination).

5

Target leakage rate
(During the operation inside the cellin the additional building)

0.1[vol%/h]

Set while referring to the acceptable leakage rate for the cell
during the Ensuring Safety PJ.

6Maximum dose rate of contents

1000[Sv/h]

7

Shielding thickness (γ rays)

280 [mm]

A 130mm separate additional shield will be installed beforehand
for structures with a high radiation dose.

Shielding thickness (neutron rays)

100 [mm]

Evaluated based on the radiation source of fuel debris

Approximate weight of thecontainers with common
specifications

520 [ton]

Only container body and lids (not including the structures)

1

2

It must be possible to store and transport
the structures retrieved on site bytransferring unitized large structures.

3

4

8

It must be possible to store structuresinside the cell in the additional building
while preventing spread of contamination.

Shielding must be possible duringtransportation of the structures.

910

Number of times it will be used

Using it multiple times is being considered11

Main material of the container

Low alloy steel

12

Material of the sealed portion

Rubber O ringContainer surface designtemperature

130 [℃]

Repeated use of the container must be
possible.

13

The design must consider generation ofheat by fuel debris.

Remarks

The main material of the container and the material of the sealed
portion have been studied during the Ensuring Safety PJ
assuming the container will be used multiple times.
Specific number of times it will be used will be studied in the
future.

Considering vibrations during transportation, and that the dual lids
will be opened and closed multiple times.
The amount of heat generated by fuel debris is set tentatively
based on estimation.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.387
retrieving large structures][Notes]Colors indicate the following② Large transfer containers
contamination levels*[Steps involved in operating the dual lids in connection with transferring structures by themethod of transferring unitized large structures (1/7)]
The steps involved in operating the dual lids while transferring structures and the primary boundaries are given below.
(1) Preparing for carrying-in the container: Removing the safety lid

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.

Enlarged view of Part A

Additional building
Building cover

Movable flange
Primary boundary

R

Work container

Y

Shielding cart

Primary boundary (area enclosed by red line)

Upper lid

Primary boundary

Water seal

Fixed flange(Fixed to theadditional building)Primary boundary-400Pa***Bellows
Sealedpart ①

Passageway
Since air-tightness is ensured by means of theupper lid (and safety lid), this zone is assumed to
be “Y” which is extremely near “G”.

Upper lid

R

R
-400Pa***Safety lid

Safety lid

Sealedpart ③

G-150Pa -64Pa

Y(G)*Safety lid

Part A(2) Carrying-in the container: Carrying-in the large transfer container(1) Preparing for carrying-in the container: Removing the safety lid

Enlarged view of Part A

Movable flange is raisedR

Shielding cart

YWork container
Transportation
Since air-tightness is ensured by means ofcartthe upper lid, this zone is assumed to be

Sealedpart ③“Y” which is extremely near “G”

Sealed part②

Upper lid

R

Part AR

Large transfer container(Lower lid)

Lower lid

Y(G)*G(R)**

Sealedpart ⑥Large transfer
container is carried inLarge transfer containerG(2)-1： Raising the movable flange(2)-2: Carrying-in the large transfer container(The large transfer container moves only in the horizontal direction)* 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”. *** Value of pressure is assumed©International Research Institute for Nuclear Decommissioning

Since the classification of contaminated areas is under examination, it could change in the future.

6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.388
retrieving large structures][Notes]Colors indicate the following② Large transfer containers
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.

[Steps involved in operating the dual lids in connection with transferring structures by the method of transferring
unitized large structures (2/7)]
The steps involved in operating the dual lids while transferring structures and the primary boundaries are given below.
(3) Connecting the container: Connecting the upper lid and

The boundaries need to be maintained bymeans of 4 sealed portions ③ to ⑥.

Enlarged view of Part A

lower lid (Large transfer container)

Movable flange is lowered

R
Sealed part ③
Work container
Shielding cart

Primary boundary (area enclosed by red line)

Sealed part ⑤

YTransportation cart

Sealed part ①Y(G)*Isolation sheet

Sealed part ④
R

Part A

R

G

Y(G)*

(3) -1： Lowering the movable flange(3)-2： Connecting the upper lid and lower lid (Large transfer container)

Large transfer
container(4) Lifting the dual lid, opening the container

G(R)**

Sealed part ⑥

If the space between the upper lid and lower lid is not completely
air-tight, the upper surface of the lower lid gets contaminated.
Hence it needs to be air-tight to some extent.

Upper and lower lid areraisedEnlarged view of Part A
Enlarged
Shielding cart

Y
Sealed part ⑤

Transportation cart

Work containerY(G)*Attached to the lower
lid by means of a hook

Sealed part ①

Container dual lid

R
R

Part AR

Large transfer
containerY(G)*The boundaries need to be
maintained by sealed
portion ④ alone.

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): Lifting the dual lid and opening the 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.389retrieving large structures][Notes]Colors indicate the following contamination② Large transfer containerslevels*
R: 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.

[Steps involved in operating the dual lids in connection with transferring structures by the method oftransferring unitized large structures (3/7)]
The steps involved in operating the dual lids while transferring structures and the primary boundaries are given below.
(5) Completely opening the container

Shielding cart

Transportation
cart

Enlarged view of Part A

Primary boundary (area enclosed by red line)
Y
Sealed part ①
Work container

R

Container dual lid

R

Y(G)*

R

G
Large transfer
container

Part A

Sealed part ④(5)： Completing opening the large transfer container(6) Placing the structures in the container

Shielding cart

Transportation
cart

Enlarged view of Part A

The structure is lowered

Y

Sealed part ①

Work container
Container dual lid

R
R
R
Large transfer
container* Assumed to be “Y” which is extremely near “G”

Y(G)*Part AG

Sealed part ④(6)： Lowering and placing the structures in the large transfer container

Since the classification of contaminated areas is under examination, it could change in the future.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.390retrieving large structures][Notes]Colors indicate the following contamination② Large transfer containerslevels*
R: 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.

[Steps involved in operating the dual lids in connection with transferring structures by the method oftransferring unitized large structures (4/7)]
The steps involved in operating the dual lids while transferring structures and the primary boundaries are given below.
Enlarged view of Part A(7) Lowering the dual lid

Sealed part ⑤Y(G)*Shielding cart

Transportation
cart

Primary boundary (area enclosed by red line)

Y

Sealed part ①

Upper and lower lid areloweredWork container

R

Container dual lidY(G)*Sealed part ④

R
Large transfer
container

R

Part AG(7)-1: Inspection and cleaning the sealed surface (removing trash, etc.)(7)-2： Lowering the dual lid(8) Closing the dual lid of the container

Enlarged view of Part A

R
Shielding cart

Transportation
cart

Y

Sealed part ③
Sealed part ①

Sealed part ⑤

Work container

Y(G)*
R

Sealed part ④

Container dual lid

R

Y(G)*
Sealed part ⑥
Large transfer
container

R

Part AG(8)： Closing the lid of the large transfer container* Assumed to be “Y” which is extremely near “G”
Since the classification of contaminated areas is under examination, it could change in the future.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.391
retrieving large structures][Notes]Colors indicate the following contamination② Large transfer containerslevels*
R: 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.

[Steps involved in operating the dual lids in connection with transferring structures by the method oftransferring unitized large structures (5/7)]
The steps involved in operating the dual lids while transferring structures and the primary boundaries are given below.
(9) Separating the container: Decoupling the upper
lid and lower lid
Enlarged view of Part A
Movable flange is raisedR

Primary boundary (area enclosed by red line)
Shielding cart

Transportation
cart

Y

Sealed part ③
Upper lid
Work containerR

Since air-tightness is ensured by means of
the upper lid, this zone is assumed to be “Y”
which is extremely near “G”

Container dual lid

R

Part A

Sealed part ②
Large transfer
container

Y(G)*

G

The lower lid of the large transfer container presses down the O ringwith its own body weight and secures it in place.

Sealed part ⑥

R(9)-1： Raising the movable flange(9)-2: Decoupling the upper lid and lower lid* Assumed to be “Y” which is extremely near “G”

Since the classification of contaminated areas is under examination, it could change in the future.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.392
retrieving large structures][Notes]Colors indicate the following contamination② Large transfer containerslevels*
R: 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.

[Steps involved in operating the dual lids in connection with transferring structures by the method oftransferring unitized large structures (6/7)]
The steps involved in operating the dual lids while transferring structures and the primary boundaries are given below.
Enlarged view of Part A(10) Transferring the container: Transferring thelarge transfer container

R

Sealed part ③

If the space between the lower lid and the container is not completely air-tight, the outersurface of the container gets contaminated. Hence it needs to be air-tight to some extent.

Large transfer container is moved

Primary boundary (area enclosed by red line)
Shielding cart

Transportation
cart

Sealed part ②

Y

Y(G)*
R

Sealed part ⑥
Work
container

Part AR
Container
dual lidR

Large transfer container (with lower lid)(10)-1: Moving the large transfer container
to the next cell which is the lid closing cell

Large transfer container

G

Structurecollection cell

Lid closing cell

Delivery cell

Sealed part ⑥R(10)-2： Moving the large transfer container to the lid closing cell

* Assumed to be “Y” which is extremely near “G”
Since the classification of contaminated areas is under examination, it could change in the future.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.393
retrieving large structures][Notes]Colors indicate the following contamination② Large transfer containerslevels*
R: 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.

[Steps involved in operating the dual lids in connection with transferring structures by the method oftransferring unitized large structures (7/7)]
The steps involved in operating the dual lids while transferring structures and the primary boundaries are given below.
(11) Installing the secondary lid: Installing the transportation lid for on-site transportation Enlarged view of Part A

Transportation lid

The bolt is fastenedY(G)*Shielding cart

Transportation
cart

Primary boundary (area enclosed by red line)

Y

Y(G)*

Work container

R

Transportation lid
Container
dual lidR

Large transfer
containerR

The large transfer container
is transported after
contamination inspection
and pressure resistance test

Sealed part ⑦
Sealed part ⑥

G
Part A

Structure collection cell

Lid closing cell

Delivery cell(11)-1： Installing a lid for on-site transportation(11)-2: Moving to the delivery cell after contamination inspection and pressure resistance test(12) Transporting to a separate building: Transporting the large transfer containers to a separate building

Fine cutting cellWork container
Shielding cart

Y

Transportation
cart
Primary boundary (area enclosed by red line)

Isolation sheet

R

R

Container
dual lid・Large transfer containers aretransported to a separate building withthe transportation lid installed.
(Transportation method is being studied.)
Receiving cell

Fine cuttingCanister

To the storage facility

New building

Transport cask

G
Safety lid

Since the classification of contaminated areas is under examination, it could change in the future.

©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]② Large transfer containers

No.394[Study on large transfer containers]⚫
⚫
⚫

Conceptual study of the method of using the large transfer container
at the actual site was conducted based on the rough outline of steps
involved mentioned earlier.
Moving the dual lid to the temporary storage cell using an overheadcrane when it is removed before storing structures in the largetransfer container, is being considered.
Raising and lowering the movable flange supporting frame with amotor operated jack for raising and lowering the movable flange isbeing considered.
Travelling rail

Temporarystorage platform

Waste
Crane

Maintenance cell

Upper lid

Part A (Waste transfer route)Temporarystorage platform

Motor operated jack x 4
Movable flange supporting frame

Temporary placement ofupper and lower lid

Movable flange
Upper lid

Hoisting accessories/cranemaintenance

Fixed flangePart B (Mechanism for raising movable flange)

Illustration of the structure of each part

Waste receptacle

Illustration of the use of 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
retrieving large structures]② Large transfer containers

No.395⚫ Moving the safety lid laterally with a link mechanism when the lid is removed is being
considered.
⚫ Study of the method of using the large transfer containers at the actual site will be
continued.
Worm speed reducer
Interlocking shaft

Ball screw

Safety lid

Raising the movable flange
Slide base
Link

Moving the safety lid

Ball screw
Drive motor with brakes
Cam follower
Link
Guide rail
Slide baseIllustration of the structure ofeach part

Position where the safety
lid is completely closed

Worm speed reducer
Position where the safety
lid is completely open

Part C (Safety lid opening/closing mechanism)©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]② Large transfer containers

No.396[Structural designing of the large transfer containers]
Structural designing of the actual large transfer containers was studied.
Upon studying the manufacturing procedures based on this structure, the items for which
manufacturing capability must be verified were identified, and the container for the element test was
manufactured.
Transportation lid
A

Lower lid
Container flange
Resin
Body

Proposed structure of the actual
large transfer container

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
retrieving large structures]② Large transfer containers

No.397[Structural designing of the large transfer container]
The manufacturing procedures were studied based on the structural design of the actual large transfer container.
・ Also, for the thickness of the container, bending plates with a thickness that enables cold bending, assembling them to form acylinder, and pasting the bent plates until the desired plate thickness is achieved, or fabricating forging material to the desired
thickness are being considered.
・ While fabricating the container body, fabricating it in 3 parts split in the vertical direction and then welding those parts is being
considered.

FlangePortion welded
while assemblingin the form of acylinderUpper body

Middle body

Bottom plate

Temporary assemblyof upper body andmiddle body

Welding the middle
body and lower
body

Arranging for forging materialof the desired thickness or

Bending the plates

Assembling toform a cylinder

Pasting bent plates

Lower body

Components before assembling
the large transfer container

Connecting the upper
body and middle bodyConnecting the middle
body and lower body

Study of the procedures for fabricating 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
retrieving large structures]
Upper lid
② Large transfer containers[Structural designing of the large transfer container]

No.398

Movable flange⚫ Considering the operation of the container flange in theactual large transfer container, manufacturing would beeasier if the structure is such that air tightness of the
movable flange and the transportation lid is ensured
respectively with the same sealed portion.
→ The structure of the container flange is an importantcomponent in achieving air tightness.

O ring(Sealed part ④)

Container flange

Detailed drawing of container
flange (with the upper lid installed)
Transportation lid
Fastening thetransportation lid
with bolts

O ring(Sealed part ④)

Illustration of a large transfer container

Detailed drawing of container flange (withthe transportation lid installed)©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]② Large transfer containers[Items to be verified by element tests (Scope of simulation of actual equipment)]
Actual equipment specifications (approximate
dimensions)ID.

Equipment

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

4)

Lower lid➢

Diameter 6800, thickness 280, weight 80 ton

5)➢Container

6)

Lifting hook➢

For development and test manufacturing

Mock-up specifications (approximate dimensions)➢No.399Simulation method for the test➢

Actual equipment-shaped is simulated.

ー➢Not simulated this time.

➢ Same as the actual equipment (Unit manufactured during
the Ensuring Safety PJ is used.)➢

Actual equipment-shaped is simulated.

➢

Actual equipment-shaped is simulated.

Diameter 8000, height 1100, weight 30ton➢

Same as the actual equipment (Unit manufactured during
the Ensuring Safety PJ is used.)

Inner diameter 6000, thickness 280, height 7500, weight390 ton➢Inner diameter 6000, thickness 50, height 3635, weight 85
ton

Diameter 500, height 1500➢

Diameter 500, height 1500

ー➢

Shape of the hook is simulated.

Differences with the mock-up structure for the dual lid test that is being 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 fabricating the actual equipment. (Bare minimum structure with which amanufacturing 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 shape that is similar
to the actual equipment)
6) Lifting hook3) Upper lid

2) Fixed flange

4) Lower lid

1) Movable flange5) Container

3) Upper lid

4) Lower lid3) Upper lid

6) Lifting hook

4) Lower lid

1) Movable flange(Fixed this time)5) Simple container
for the test
Illustration of actual
equipment

Illustration of the mock-up structure for the
Ensuring Safety PJ5) Container
for the test6) Lifting hook

1) Movable
flange(Can be raised
and lowered)

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
retrieving large structures]② Large transfer containers[Element test plan (Large transfer container for the element test
It was decided to fabricate 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 which was about half of the height of theactual container (7.5m) considering that the height was sufficient aslong as the plate can be bent and welded.

No.400

Rough specifications)]
Large transfer container for the element test

Component table

Product
NumberProduct Name

Numberof units

Material

Remarks

1

Container
flange1SF440A

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

Outer diameter of the container
for the test： φ6100④ Side support(Mold steel)The upper body of the container is manufactured in parts bybending a 50t steel plate.

② Body⑤ Bottom support(Mold steel)

3835

Depth of the container
for the test: 3585

Inner diameter of the container
for the test:φ6000

3635

350

① Container flange③ 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
retrieving large structures]② Large transfer containers

No.401[Element test plan (Sealed parts to be verified by the test)]
Considering the operational steps at the actual site, the air-tightness of the following 4 sealed portions 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 lids, opening thecontainer(7) Lowering the dual lids

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)-2 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 ③
Sealed part ④

Sealed part ④

Sealed part ⑤

Sealed part ⑤
Sealed part ⑥
Sealed part ⑥©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]② Large transfer container

No.402[Element test plan (conceptual image of the test)]
The dual lid manufactured during the Project of Ensuring Safety will be used, the largetransfer container will be test manufactured and element tests will be conducted to verify
feasibility and identity issues.
[Items to be verified by means of the element tests (proposed)]・ Method of remotely monitoring the raising and lowering movement of the movable flange
・ Verification of the impact of misalignment of the movable flange and the large transfer
container→ Air-tightness of the sealed portions will be verified.
(In particular, the impact on air-tightness between the movable flange and thecontainer flange will be verified,)Movable flange
Dual lids

Raising and lowering the movable flange

Raising and lowering the dual lids

Illustration of the large transfer container element test
©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]② Large transfer container

No.403: Planned: Actual◼ Development Process
FY2021

Study items
4

Major milestones

5

6

7

8

9

10

11

Interim Report▼

FY2022
12

1

2

3

4

5

Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

12

1

2

3

Final
report
▼1. Conceptual study
2. Element testplanning

3. Test preparation /Testmanufacturing oftest equipment
4. Element tests
5. Summary

Remarks©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]② Large transfer container: Summary

No.404➢ Preconditions pertaining to large transfer containers were consolidated and thedevelopment policy was studied.
➢ The aspects to be covered by the simulation during the test were studied considering
the procedure of fabricating large transfer containers.
➢ Structural designing of large transfer containers is underway. As the structure of thecontainer flange is important for ensuring air-tightness, the plan is to fabricate thecontainer for the element test considering the structure of the actual equipment andverify air-tightness through element tests.
➢ The plan for the element tests mentioned above is being developed. In the future, thefeasibility of the large transfer container will be verified by element tests.

©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]

No.405

Solicitation items are listed.

③ Large transportation equipment
With respect to retrieving fuel debris and reactor internal structures, in order to enhance the throughput
using the top access method, the method of transferring unitized large structures is being studied as part ofthe development being undertaken since FY2019. To make this method possible, large structures need to be
separated from the reactor and transferred, however, the large transportation equipment inside the R/B thatwill be used for transferring those structures needs to be developed so that the structures separated fromthe 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 the operating
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 a cart, generally one that is
towed with a wire can have a lower floor as compared to the automated one, and is suitable for reducing thesize as well. However, if an air-tight gate will be installed for compartmentalizing contaminated areas, suchtransportation equipment will be difficult to use. Such preconditions for the large transportation equipment
and items that need to be developed for its use will be studied and consolidated, the methods for properlytransporting large and heavy contaminated structures including their applicability when there is an air-tightgate will be investigated and studied, the structure of the transportation equipment including the drive
mechanism will be studied and element tests will be conducted for evaluating the on-site applicability of thelarge transportation equipment, and consolidating related issues.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept ofNo.406
retrieving large structures][Notes]Colors indicate the following③ Large transportation equipment
contamination levels*[Status of studies up to FY2020]⚫ Conceptual study of the method for reducing the high contamination areas inside the passageways was
conducted.
⚫ The method of transporting structures using carts was studied.
(Passageway method)(Passageway method) Revision 1
Setting up partitions using gates
Secondary boundary

Secondary boundary
Retrieval equipment

Conceptual drawing

Passageway

Retrieval equipment

Gate opening/closing
equipment(Passageway method) Revision 2
Setting up partitions using work containers
Secondary boundary

Passageway

Passageway

Work container

Gate
Additional opening/closing
equipment
building

Additional buildingGate
opening/closing
equipment
Transportation
cart

R

Work
container

Retrieval equipment

Passageway
Additional building

Connection
sleeve

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, and the red zone
is marked with a red border.

Dual lid
Dedicatedtransportation
containers

Connection
sleeveY

Connection
sleeveTransportation
cart

Dual lid
Dedicatedtransportation
containers

Connection
sleeveTransportation
cart
Work
container

Dual lid
Dedicatedtransportation
containers

Transportation
cart

While transferring
the containerG

MeritsDemerits

・Simple retrieval procedure・Equipment made up of few components,
small quantity of waste

・

・

・

Radioactive dust generated during cutting
gets dispersed directly into thepassageways (Large accumulation ofradioactive dust)

Reduction in dispersion of radioactive dust
generated during cutting into thepassageways by closing the gates

When the gate is closed, it causesinterference for the rail and travel drive part・ Radioactive dust adhered to the structures
disperses into the passageways duringtransportation

・

Reduction in dispersion of radioactive dust generated
during cutting into the passageways by means of work
containers
・ Reduction in dispersion of radioactive dust into thepassageways while transporting structures, by using
work containers for transportation
・ Quantity of secondary waste increases due to additionof work containers.
Note: Since the underside of the working container is not
closed, it remains open momentarily at the time oftransferring on to the transportation cart.

⇒ In order to reduce accumulation of radioactive dust into the passageways, the method described in (Revision 2) was
studied as the main proposal. Specific studies will be continued.
©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]③ Large transportation equipment

No.407[Issues]•
If shielding will be accomplished by means of the passageways, the weight will increase depending on the shielding method, and theequipment scale will also increase.
•
If air-tightness will be ensured by means of the passageways, contamination is likely to spread throughout the passageways.
•
Since the items to be transported are heavy, the impact of loading heavy items on the transportation equipment needs to beconsidered.
[Implementation details]•
The method of reducing contamination inside the passageways when large
structures are transported will be studied, and the preconditions and the items
that need to be developed pertaining to the large transportation equipment
Crane(shielding cart and transportation cart) considering that method will be(Passageway)
consolidated.
•

Existing technology and track record, etc. related to the method of properlytransporting large and heavy structures will be investigated and studied.

Shielding cart
Passageway•

The configuration of the large transportation equipment including the drive
mechanism will be studied. Also,
the impact of loading heavy items on traveling will be studied.
•Viability of the placement of the large transportation equipment and its drive
mechanism inside the passageways will be studied.
•

Element tests will be planned and implemented, on-site applicability of thelarge transportation equipment will be evaluated and issues will beconsolidated.

Transportation cart
(Localized shielding)(Note) “Large transportation equipment” refers to“Shielding cart” and “Transportation cart”.

[Expected outcome]• Presentation of a method of properly transporting large and heavy contaminated structures.

©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]③ Large transportation equipment

No.408[Implementation details]

Implementation items

Implementation details

Consolidation of preconditions

The method of reducing contamination inside the passageways when large
structures are transported will be studied, and the preconditions when thelarge transportation equipment is used considering that method will beconsolidated.

Investigation and study ofexisting technology and trackrecord, etc.

Existing technology and track record, etc. related to the method of properlytransporting large and heavy structures will be investigated and studied.

Study of large transportationequipment

・ The configuration of the large transportation equipment including the drive
mechanism will be studied.
・ The impact of loading heavy items on traveling will be studied.

Study of the availability ofplacement of largetransportation equipment

・ Viability of the placement of the large transportation equipment and its
drive mechanism inside the passageways will be studied.

Element tests planning andimplementation

・ Element tests will be planned and implemented, on-site applicability of thelarge transportation equipment will be evaluated and issues will beconsolidated.

©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]③ Large transportation equipment

No.409[Preconditions]• Preconditions pertaining to the large transportation equipment are indicated below.

ID.

Preconditions

Basis

1

An additional building for the top access methodshould 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 is being considered. Hence itwould be difficult to use the delivery equipment incommon with the side access method.

2

A frame should be installed so that the load of thepassageway in which retrieval equipment, etc. will be
installed is supported by the ground surface. The
transportation cart travels on the frame.

Considering the acceptable maximum load of theoperation floor, it will be difficult to support the loadof the passageway.

3

The transportable weight should be studied
considering that structures and work containers willbe transported.

The study should be conducted while reflecting
the status of the study of retrieval methods suchthat structures and work containers can betransported.

©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]③ Large transportation equipment

No.410[Study of transportation methods and equipment]
Issues with the transportation cart having a low floor and an overview of the study are given below. Element tests will be conducted as
required to verify feasibility.
＊ Issues with using a generic cart (Remotely◆ Example of investigation of traveling systems
Proposal 1: Wheeled system

Rail

Remotely operated
transportation cart

Remotely operated wheels(With drive motor)

MeritsTransportation cart

Demerits

Traveling

Remotely operated wheels

approx. 2m or more due to theremotely operated wheels and rail,a larger passageway is requiredEndless roller

・ Can have a low floor

・ Can have a low floor

・ Requires a higher floor height due toremotely operated wheels and rail (assumed tobe approx. 2m or more)・ As it does not have a remote operation
functionality, it requires an external towing or
drive mechanism
・ Load distribution needs to be considered・ As it does not have a remote operation
functionality, it requires an external towing or
drive mechanism
・ As air is constantly blown against the floor,
quantity of gaseous waste to be treatedincreases

TravelWire (connected to
the winch)

Maintenance(increases the load on R/B).

Proposal 3: Underground drive
mechanism system

Drive motor(Outside thepassageway)

Proposal 4: Trapezoidal screw thread
drive system

Drive motor (inside AT/Cell)
Sprocket
TravelPin rack

Endless roller

MeritsResults of theinvestigation andstudy of existing
technology andtrack record, etc.
will be reflected.

Proposal 2: Jack towing system

Conceptual
drawing

TravelDemerits

transportation cart, as its height isCenter plate

Proposal 3: Air caster system
Air

Frame body

◆ Example of investigation of drive systems

Issues in the remotely operated

In the case of a remotely operated

Ground contact
area

Plate

Pin

・ The drive motor can be connected to the axle
(Can have a remote operation functionality)

Proposal 1: Wire towing systemtransportation cart

Proposal 2: Endless roller system
RollerConceptual
drawing

operated transportation cart) and response measures

Wire
connection

Endlessroller

Cylinderjack

Guide (wire,
rail, etc.)

Endless roller

Drive motor (Outside
the passageway)

Guide
Trapezoidal screw
thread・ The cart structure can be
simplified.
・ Highly flexible in terms ofplacement of the drive member(winch, etc.)

・ The cart structure can be
simplified.

・ The cart structure can be
simplified.
・ The drive motor and the cable canbe placed outside the passageway.

・ The cart structure can be simplified
・ The drive motor and the cable canbe placed outside the passageway.
・ High positioning accuracy

・ If there is a gate in the area
where this system will move,interference avoidance is required.

・ If there is a gate in the area where
this system will move, interference
avoidance is required.
・ The hose of the cylinder jack needs
to be routed in accordance with the
movement of the cart.

・ There are issues in the method of
re-engaging the rack and sprocket inaccordance with the movement of
the cart.
Re-engagement

・ If there is a gate in the area where
this system will move, interference
avoidance is required.

・ The drive member (winch, etc.)
gets contaminated due to windingof wire, and hence requires special
attention.

・ The drive member (cylinder jack)gets contaminated as it isintegrated with the cart, and hence
requires special attention.

Transportation
cart

TravelSprocket・ The impact of contamination is less as thedrive member (motor) is placed outside thepassageway.
・ However, measures to prevent dirt fromgetting stuck on the rack surface will continue
to be studied as an issue.

The impact of contamination is less as thedrive member (motor) is placed outside thepassageway.
・ However, measures to prevent dirt fromgetting stuck into the trapezoidal thread
screw will continue to be studied as an issue.

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.411
retrieving large structures][Notes]Colors indicate the following contamination levels*③ Large transportation equipment
R: Red (high contamination) zone

Y: Yellow (moderate contamination) zone
G: Green (low contamination) zone
*Besides color, the main zones are marked as R, Y andG, and the red zone is marked with a red border.

[Study of transportation methods and equipment]
A shielding cart for shielding the radiation dose from the PCV and a transportation cart fortransporting work containers will be used as large transportation equipment which travel thesame route inside the passageways.
While studying the large transportation equipment, the engagement between the isolation
sheet and the work container being studied as a method for reducing contamination inside
the passageways will be considered.

Isolation sheet

Items

Overview

Illustration of confinement by means ofisolation sheet

Shielding cart

Cart for shielding radiation dose from the PCV.

Transportation
cart

Cart used between the well and the additional building.
Transports work containers.

Shielding cart

Carrying-in work container A

Work 作業容器
container

Shielding cart
遮へい台車

Isolation sheet

R

Y

搬送台車
Transportation
cart

Illustration of carrying-in of work container (Before the transportation cart retreats)

Polar craneTransportation cart

Illustration of carrying-in of work container (After the transportation
cart retreats)©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]③ Large transportation equipment

No.412[Functions required of large transportation equipment]
Functions required of the large transportation equipment are indicated below.
Details are being studied along with the overall steps involved in the method of transferring unitized large structure,but it was decided to study the structure of large transportation equipment viable based on the current assumed
values.
ID.

Items

Required functions

Course of study in this project1

Shielding
performance

Should be able move up to the top of the reactor well and shield the radiationdose from inside the reactor
Results of the conceptual study conducted in FY2020: External appearance
L14×W14×H0.18m

The structure will be studied considering the engagement between
the work container and the isolation sheet.

2

Transportation
weightShould be able to transport work containers containing structures (Tentative
weight: Approx. 600 ton)
(Weight of work container shielding approx. 330ton, structures (reactor bottom)
approx. 250ton, ＋α)Will be revised as needed based on the results of the study on the
structure of the work container

3

Transportability
between cells

Should be able to move between multiple cells

Conceptual study will be conducted including the study onplacement inside the passageways and additional building.

4

Air-tightness

Considering movement between multiple cells, structures such as rails, etc. arelikely to be laid across multiple cells.
In that case as well, it should be possible to secure air-tightness between the cells.

Same as above

5

Maintainability

It should be possible to remotely perform maintenance inside the passageways orin the additional building.

Same as above

6

Positioning
capability

Should be able to be positioned at the prescribed position even when the abovementioned transportation weight is loaded

Conceptual study will be conducted on a movement mechanism
which provides positioning considering the procedures for the
method of transferring unitized large structures.

7

Seismic
resistance

Should not get overturned in the event of an earthquake, when loaded with work
containers containing structures.

Seismic resistance will not be evaluated, but conceptual study will
be conducted considering seismic resistance.

8

Impact resistance

The integrity of the structures should be ensured even if the work container falls
on the large transportation equipment.

Impact resistance will not be evaluated, but conceptual study will
be conducted considering impact resistance.

9

Corrosion
resistance

The structure should prevent corrosion or should be able to withstand corrosion.

Corrosion resistance will not be evaluated, but conceptual study
will be conducted considering corrosion resistance.
©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]③ Large transportation equipment

No.413[Overview of the course of development of large transportation equipment]
While using the method of transferring unitized large structures, work containers are loaded on the largetransportation equipment and transported from the passageways to the additional building.
In order to reduce the contamination of the passageways and the additional building, the method of installing gatesand dividing the area into several cells to prevent extensive spread of radioactive materials can be considered.
As part of that, large transportation equipment will be necessary to be transported between several cells, and in thecase of the aforementioned wire towing system or trapezoidal screw drive system, or when the equipment isremotely controlled, since the cables, hose, etc. interfere with the gates, securing the boundaries is a challenge. A
brief study of the transportation system will be conducted considering these aspects.
Air-tight gate
Processing area crane

Crane

Crane

Crane

Maintenance cell

Shielding cart

Transportation cart

Interference withthe gate and cable

Power cable fordriving the cart

Illustration of the large transportation equipment (The layout of the additional building is being examined. This drawing is based on FY2020 results.)©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]③ Large transportation equipment

No.414[Implementation details (Overview): Study of the placement of the large transportation equipment and its drive mechanism inside thepassageways]
The placement of the large transportation equipment and its drive mechanism will be studied based on the results of studies conducteduntil FY2020.
Additional building(Example image of the location)<Results of studies conducted until FY2020>
R/B

Crane

Shielding
cart

Drive mechanism chamber(An example)

Crane
350ml
(87.5t×4)

Transport
ation cart

Drive Mechanism

Maintenance cell

TransferoutletCarrying-in
cart

Processing area

➢Study of a drive system that assumes that individualcarts will travel independently and study of the placementof the drive mechanism part will be conducted.

Processing area crane
Carrying-in craneService entrance

Processing area equipment
Maintenance cell

©International Research Institute for Nuclear Decommissioning6. Implementation Items of This Project [2) (1) Development of technology for realizing the concept of
No.415
retrieving large structures][Legend]○: Few issues in application③ Large transportation equipment△: Issues in application▲: Many issues in application[Overview of the results of the study of large transportation equipment]

Results of the brief study conducted considering movement between multiple cells are given below. Details are provided later.
In this project, elements that pose issues will be test manufactured and the viability of the large transportation equipment will
be verified.
(1) Motor operated
transportation system(2) Wire transportation system(3) Screw shaft typetransportation system(4) Shuttle transportation system(5) Wire towing system

Transportability
between cells○: No interference with the gate
(Cable bear installed for each cell)○: No interference with the gate
(Drive mechanism installed for each cell)○: No interference with the gates(Trapezoidal screw installed for each cell)△: No interference with the gate, but notsuitable for moving between multiple cells
due to the mechanism▲: Measures are required as there isinterference with the gates

Air-tightness△: Maintenance of the connector andthe cables△: Wire passes through to the outside of
the cell→ Improvement by means of secondary
containment△: Screw shaft interferes with the gate
→ Improvement by means of secondary
containment△: Motor operated cylinder installedoutside the cell
→ Improvement by means of secondary
containment▲: Wire interferes with the gate

Maintenancecapability▲: Repairs need to be performed inside
the cell△: Contamination is likely to spread via
the wire△: Maintenance can be performed outside
the cell(Contamination accumulates on the screw
itself)○: Maintenance can be performed outside
the cell△: Contamination is likely to spread via
the wire

Positioning
capability△: Depends on motor performance△: Depends on the performance of the wire
mechanism that activates the hook○: Enhanced stop system can be expectedby controlling the screw shaft▲: Positioning accuracy is low due to thenature of the mechanism△: Depends on the performance of themechanism that activates the wire

Seismic
resistance○: Planned to move along the rail andhence the risk of overturning is small△: Fixed with a hook△: Fixed with a screw shaft▲: The cart cannot be fixed△: Planned to move along the rail andhence the risk of overturning is small

Manufacturing
capability○: Proven track record of remotely
performed small air-tight connection○: Proven track record of fabricating asmall unit and thus transporting heavy
items is feasible▲: Issues in manufacturing capability oflarge screw shafts○: Comparatively simple structure○: Comparatively simple structure

Conceptual
drawing

Evaluation

△

△

△

▲

▲

©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]③ Large transportation equipment

No.416[Conceptual study of the structure of the large transportation equipment](1) Motor operated transportation system
・A cable bear and connector positioning unit is installed in each cell.
・A connector socket is provided on the front and rear end of the cart. The connectors are switched remotely while the cart
moves between cells.
Connector
Connector positioning unit

B-1: Cable bear

B-2: Cable bear

C-1: Cable bear

C-2: Cable bear

A-1: Cable bear

B-1: Cable bear

B-2: Cable bear

C-1: Cable bear

C-2: Cable bear

A-1: Cable bear

B-1: Cable bear

C-1: Cable bear

C-2: Cable bear

Cable bear

Overview
Cable bear and connector positioning unit are
installed in each cell.
A connector socket is provided on the front
and rear end of the cart. The connectors are
switched remotely while the cart moves
between cells.

B-2: Cable bear

C-2: Cable bear

B-1: Cable bear

B-2: Cable bear

C-1: Cable bear

©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]③ Large transportation equipment

No.417[Conceptual study of the structure of the large transportation equipment](2) Wire transportation system
・ The wire that is passed through the cell wall is powered up to move the cart.
・ The cart is moved by powering up the wire after the towing dock installed on the cart side is tucked on to
the towing hook which opens when a predetermined tension is applied.

Transportation unit

End unit

Tension unit

Inside the cell

Drive unit

Outside the cell
Towing hookTension unit

Transportation unit
Drive unit

Towing dock (cart side)

Towing dock(cart side)

Towing hook
Guide rail
Rail for the cart

Transportation unit

Portion enlarged©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]③ Large transportation equipment

No.418[Conceptual study of the structure of the large transportation equipment](3) Screw shaft type transportation system
・ The screw shaft of the trapezoidal screw is rotated from outside the cell.
(In the figure below, the screw shaft is rotated from the end of the passageway, but in the case of multiple cells it needs tobe driven from the cell wall side (side).)・ The cart moves by means of the driving force obtained when the half nut installed on the cart engages with the trapezoidal
screw.
Transportation cart drive unit

Shielding wall

Transportation
cart drive unit

Transportation cart

Shielding wall drive unit
Shielding wall

Shielding wall drive unit

©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]③ Large transportation equipment

No.419[Conceptual study of the structure of the large transportation equipment](4) Shuttle transportation system
The cart is moved by pressing the dock installed on the cart by moving the rudder (frame with a hook roller)
back and forth by means of the cylinder installed at the end of the tunnel.
・ The structure is simple, but there are many issues such as difficulty in accurate positioning, etc.

Cylinder for the shuttle
drive system

CylinderTowing dock(cart side)Rail

Towing dock(cart side)
Hook

Hook roller

Stopper©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]③ Large transportation equipment

No.420[Conceptual study of the structure of the large transportation equipment](5) Wire towing system
・ In this system, the structure is such that the cart of the large transportation equipment moves by means ofrollers, and the cart is towed by means of a drive mechanism such as wire, etc. from outside the cell.
・ After the cart has moved up to another cell, when the gate is being closed, the wire interferes with thegate and thus there is an issue in terms of air-tightness.

Wire

Wire interferes with the gate

Wire
Drive
Mechanism©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]③ Large transportation equipment

No.421[Element tests planning and implementation]
Items to be test manufactured and verified by element tests are being examined based on the aforementioned
issues in the large transportation equipment.
Prospective large transportation equipment will be selected based on the results of those element tests.
Studies will continue to be conducted and element tests will be planned considering the following items asprospective options.
(1) Whether or not the large connector can be remotely connected in the motor operated transportation system(2) Viability of transporting heavy items with the wire transportation system(3) Air-tightness between the drive part such as the wire, etc.

©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]③ Large transportation equipment

No.422:Planned: Planned(after revision)*: Actual◼ Development Process
FY2021

FY2022

Study items
4

Major milestones

5

6

7

8

9

10

11

12

1

2

3

Interim Report▼

45Interim Report
▼

6

7

8

9

10

Interim Report
▼

11

12

1

2

3

Final report▼

1. Conceptual study

2. Element test planning
3. Test preparation /Test manufacturing oftest equipment
4. Element tests

5. Summary
As the items to be tested in the element tests will be identified based on the details on compiled issues, the element test plan will be createdafter the issues have been compiled.
Remarks

The steps involved in carrying-in/out including the work container and the isolation sheet are being studied. The study of large transportationequipment will be continued in accordance with those steps. As the study of the steps involved in carrying-in/out requires time, consolidationof the issues pertaining to the large transportation equipment and development of the elemental plan based on those issues is planned to be
implemented in FY2022 (Development is expected to pick up speed from FY2022 and is expected to be completed in FY2022.)* 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
retrieving large structures]③ Large transportation equipment: Summary

No.423➢ Preconditions pertaining to the structure of the large transfer equipment wereconsolidated and the development policy was studied.
➢ The motor operated transportation system, wire transportation system, screw shaft
transportation system and shuttle transportation system were studied with respect tothe structure of the large transportation equipment, and issues were consolidated.
➢ Element test plan related to the large transportation equipment will be created and thefeasibility will be verified by element tests.

©International Research Institute for Nuclear Decommissioning7. Summary

No.424

1） Development for the side access method(1) Development of the method of installing access equipment① Installation of large heavy structures➢ The structure was studied focusing on connected parts, assembled parts and installed part
related to the cell adapter of the access equipment, shielding door, and fuel debris retrieval
cell.
➢ The access equipment and other fuel debris retrieval equipment cells need to be installedaccurately in a straight line between the pedestal opening and the X-6 penetration opening, inorder to establish the shortest access route. Hence, the installation procedures and structure
were studied, and further feasible proposals were developed considering the installation
accuracy.
➢ The work steps involved in installing large heavy structures were detailed and revised, andissues in each step were identified,➢ The measures for responding to the issues identified in the steps involved in installation work
were clearly specified.
➢ Since the work of installation would be carried out under high radiation dose environment, thecell adapter would need to be installed by remote operations. Hence the detailed steps
involved in the installation procedure were consolidated and related isuues were compiled.
Also, a test plan for clarifying the required conditions for the remotely controlled equipment isbeing created along with substantiating the structure.
➢ As a part of the study for enhancing throughput, the work carried out inside the cells wasdetailed for improving the accuracy of the results of calculating throughput.
©International Research Institute for Nuclear Decommissioning7. Summary

No.4251） Development for the side access method(1) Development of the method of installing access equipment (Continued)② ＰＣＶ connection sleeve remote installation and welding➢ Pre-conditions pertaining to remote installation of the sleeve were compiled, and the delivery method andresults of the study of the equipment were consolidated. “The method of delivering the whole unit” which isthe same as the method used for delivering the main access tunnel was selected, and the issues and items
that need to be verified by tests, etc. were consolidated. Details of 3D measurement, camera placement, etc.
are being examined.
➢ The target height while delivering the PCV connection sleeve was set to 4000mm which is the same as theheight while delivering the access tunnel. Prospects of being able to achieve a height of 4000mm or lower bymodifying the remote installation equipment were seen.
➢ The methods of responding to the issues pertaining to remote welding of the sleeve consolidated during the
FY2019-20 subsidy project were studied, and issues as well as items that need to be verified by tests, etc.
were consolidated. Details such as study of test equipment including the welding torch, inspection method,etc. are being examined.
➢ Element test plan is being studied along with remote installation, remote welding of the sleeve, and the test
equipment and facility are being arranged for. In the future, the feasibility of remote installation of the sleeve,
the welding procedures and the equipment will be verified by element tests.

③ Installation of shield➢ The course of study and preconditions for studying the method of providing additional shield wereconsolidated. Shielding was evaluated and it was found that as the radiation dose from neutron beams ishigh, neutron shielding needs to be installed to reduce the shielding thickness.
➢ For shielding that will be installed later, iron plate delivery, filling of iron balls, casting, mortar filling are being
studied considering shielding performance and workability, and comparative evaluation is being carried out.
In the future, comparative evaluation will be carried out with the schematic view, and the proposal for
additional installation will be selected.
➢ In the future, the feasibility of installation of additional shielding will be verified by tests.

©International Research Institute for Nuclear Decommissioning7. Summary

No.426

1） Development for the side access method(1) Development of the method of installing access equipment (Continued)④ Disassembly of shield plug
➢ The course of study and the preconditions pertaining to the method of transferring
unitized structures for the shield plug in Unit 1 were consolidated, and a brief
study of the removal procedures was conducted. The disassembly procedures
were consolidated.
➢ The course of study and preconditions pertaining to the method of disassembling
the concrete blocks in Unit 2, 3 were consolidated, and the disassembly andremoval procedures were studied briefly. The disassembly procedures wereconsolidated.
➢ Issues in the procedures for disassembling and removing the shield plug in Unit 1
and the concrete blocks in Units 2 and 3 were identified, and the roughly estimatedradiation dose was assessed. Although either of the disassembly methods are
general disassembly methods, as the concrete blocks have an impact on the
installation accuracy of the PCV connection sleeve, element tests on
disassembling the concrete blocks will be conducted in the future.
➢ In future, processing tools will be evaluated and the feasibility of the methods will
be verified by element tests.

©International Research Institute for Nuclear Decommissioning7. Summary

No.4271） Development for the side access method (Continued)(2) Development of disassembly and removal technology① HVH disassembly➢ Pre-conditions pertaining to HVH disassembly were consolidated. Results of studies concerning theselection of items to be tested based on the level of difficulty of disassembly, selection of circular
saw and reciprocating saw as the cutting technology, and identification of element test items basedon the disassembly work steps have been compiled.
➢ The work steps were examined in detail, and issues in each of the steps were identified.
➢ The test equipment such as HVH disassembling robot, crane, etc., and the cutting tools such as tip
saw, etc. were studied, and their specifications were consolidated.
➢ Based on the results of above mentioned studies, the element test plan was created, and element test
items, judgment criteria, etc. were studied. In the future, the feasibility of the method ofdisassembling and removing the HVH will be verified by element tests.
② Disassembly of CRD exchanger➢ Pre-conditions pertaining to CRD exchanger disassembly were consolidated.
➢ Technologies that must be developed in common for Units 1/3 were identified upon studying themethod of disassembly and removal of CRD exchangers in Units 1/3 and the work steps involved.
➢ Basic tests were conducted to verify the viability of carrying-in the equipment through the CRD
opening and lifting up → loading → transferring the disassembled pieces, under a test environment
simulating Unit 2, and prospects of actual equipment applicability were seen.
➢ In the future, work steps specific to each unit will be studied in detail, the disassembly and removal
equipment will be designed and test manufactured, an element test plan will be drafted, and thefeasibility of the method of disassembly and removal of CRD exchanger will be verified by element
tests.

©International Research Institute for Nuclear Decommissioning7. Summary

No.4281） Development for the side access method (Continued)(2) Development of disassembly and removal technology (continued)③ Removal of interfering objects from inside the 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 as preconditions for removing interfering objects from inside thepump pit.
➢ The work steps involved in removing interfering objects from inside the pump pit
were studied, and test items were selected.
➢ Detailed study of the work steps is underway. Illustrations of the work of removing
the existing pump from pump pit (225°) inside PCV in Unit 1 were consolidated.
➢ The simulated pump and pump pit, and the hoisting equipment to be used for theelement test are being studied. In the future, element test plan including the study
on disassembly equipment, etc. will be created, and the feasibility of the method
for removing interfering objects from inside the pump pit will be verified byelement tests.

©International Research Institute for Nuclear Decommissioning7. Summary

No.4291） Development for the side access method (Continued)(3) Advancement and development of retrieval methods① Remote controlled tip tools for retrieval
Tip tool➢ Throughput computations from the past were analyzed, and processing tests for reducing the time requiredfor processing block fuel debris accumulated at the pedestal bottom were selected as element tests.
➢ Circular cutter for interfering objects, core boring for block fuel debris, which have not undergone processing
tests as a tool, were identified as element test items based on the status of implementation of past deskstudies and processing tests.
➢ The specifications required of the above-mentioned tools have been consolidated and conceptual studies andelement test planning are underway.
Operation system➢ The work flow for fuel debris retrieval was studied.
➢ Details of manipulator work and remote operation method during each phase of the work flow wereconsolidated.
➢ For works wherein the operator focuses on the arm tips such as “grabbing”, “cutting”, etc., measures werestudied to automate obstacle avoidance by the elbow of the manipulator. The method of implementing thesystem is being examined.
➢ The function of sounding an alarm or initiating interlock shutdown when the distance between the obstacle
and manipulator goes below a certain value was studied. The method of implementing the system is being
examined.
➢ A 3D model is used for determination of collision. Hence, there is the risk of interference if there is any
deviation on site. A mechanism for correcting deviations using point cloud data acquired by scanning the sitewith a laser scanner, etc. in response to this issue was studied.
©International Research Institute for Nuclear Decommissioning7. Summary

No.4302） Development for the 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 were consolidated.
➢ Conceptual study was conducted on the method of disassembling the RPV head, method of fillingand solidification of the reactor core, etc. and the method of cutting reactor internal structures.
➢ The element test plan related to cutting of RPV head bolts was created. 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 feasibility of the method of cutting the RPV head bolts was verified,and issues are being consolidated.
➢ The element test plan for cutting the reactor internal structures is being created. In the future, thefeasibility of the method of cutting of reactor internal structures will be verified by element tests.
② Large transfer container➢ Preconditions pertaining to large transfer containers were consolidated and the development policy
was studied.
➢ The aspects to be covered by the simulation during the test were studied considering the procedureof fabricating large transfer containers.
➢ Structural designing of large transfer containers is underway. As the structure of the container flange
is important for ensuring air-tightness, the plan is to fabricate the container for the element test
considering the structure of the actual equipment and verify air-tightness through element tests.
➢ The plan for the element tests mentioned above is being created. In the future, the feasibility of thelarge transfer container will be verified by element tests.

©International Research Institute for Nuclear Decommissioning7. Summary

No.431

2） Development for the top access method (Continued)(1) Development of technology for realizing the concept of retrieving large structures（Continued）③ Large transportation equipment➢ Preconditions pertaining to the structure of the large transfer equipment wereconsolidated and the development policy was studied.
➢ The motor operated transportation system, wire transportation system, screw
shaft transportation system and shuttle transportation system were studied withrespect to the structure of the large transportation equipment, and issues wereconsolidated.
➢ Element test plan related to the large transportation equipment will be created andthe feasibility will be verified by element tests.

©International Research Institute for Nuclear Decommissioning8. Specific goals for achieving the purpose of the projectNo.432① Installation of large heavy structures
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 through element tests.
(Target TRL at completion: Level 4)② PCV connection sleeve remote installation and welding
The method of remotely installing the access tunnel sleeve connected to the
PCV should be studied, the requirements should be consolidated, and feasibility
should be shown through element tests. Also, feasibility of the method of welding
by remote operations should be shown through element tests.
(Target TRL at completion: Level 4)③ Installation of shield
Feasibility such as manufacturing capability, etc. of the access tunnel shieldshould be shown through element tests.
(Target TRL at completion: Level 3)④ Disassembly of shield plug
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)(2) Development of disassembly and removal ① HVH disassembly
technology
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)1) Development for the side access method(1) Development of the method of installing
access equipment©International Research Institute for Nuclear Decommissioning8. Specific goals for achieving the purpose of the projectNo.433

1) Development for the side access method② Disassembly of CRD exchanger(Continued)
Feasibility of specific cutting/collection methods with regards to the method of(2) Development of disassembly and removal removing the CRD exchanger, which is a large structure located at the center oftechnology (continued)
the pedestal, should be shown through element tests.
(Target TRL at completion: Level 3)③ Removal of interfering objects from inside the pump pit
Feasibility of the method of cutting, etc. and transferring with regards to themethod of removing interfering objects from inside the pump pit, which is requiredfor installing the submersible pump into the pump pit inside the PCV, should beshown through element tests.
(Target TRL at completion: Level 3)(3) Advancement and development of① Remote controlled tip tools for retrieval
retrieval methods
The viability of a series of operations from processing interfering objects andfuel debris from inside the PCV to collecting the cut pieces in unit cans should beshown through element tests, etc., and data for evaluating the throughput shouldbe acquired.
(Target TRL at completion: Level 3)2) Development for the top access method① Method of cutting large structures(1) Development of technology for realizing
Feasibility of the cutting and separating with regards to the method of cutting
the concept of retrieving large structures
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)② Large transfer container
The performance of the container in which unitized structures are stored andtransferred when the top access method is used, should be verified by element
tests, and the issues in site applicability should be indicated.
(Target TRL at completion: Level 3)©International Research Institute for Nuclear Decommissioning8. Specific goals for achieving the purpose of the project2) Development for the top access method(Continued)(1) Development of technology forrealizing the concept of retrieving
large structures (Continued)

TRL level

No.434③ Large transportation equipment
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 by element tests,
and the issues should be consolidated.
(Target TRL at completion: Level 3)

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.

TRL4

Stage at which functional tests are implemented at the test manufacturing level as adevelopment and engineering process.

TRL3

Stage at which development and engineering are being carried out by applying or
combining past experiences. 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

Simulated verification
Research forpractical use©International Research Institute for Nuclear DecommissioningNo.435

Explanation of terminology
No.

Term

Explanation

1

Fukushima Daiichi NPS

Fukushima Daiichi Nuclear Power Station

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

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 of Japan, etc.
©International Research Institute for Nuclear Decommissioning