JANTI-SANE-G2 Version1

Post-Earthquake Equipment Integrity Assessment Guideline[Inspection Method: Pipes, Foundation Bolts](Tentative Translation of Main Text)

March 2012

Japan Nuclear Technology Institute0Disclaimer
This guideline was enacted after discussions by committee members and participants with expert
knowledge and interest at the “Structural Integrity Assessment for Nuclear Power Components experienced
Niigata-ken Chuetsu-oki Earthquake Committee” (SANE) which was established by the Japan Nuclear
Technology Institute (JANTI).
JANTI is accountable for the content of the guideline, but is not responsible for any problems that
may arise through use of the guideline. In addition, JANTI does not approve or guarantee
inspections, assessments, and other actions that are conducted in accordance with the guideline.
Therefore, the user of this guideline is responsible for use of this guideline and should be awarethat he or she is responsible for the problems that arise as a result of activities related to thisguideline and compensation regarding the infringement of the intellectual property rights of a third
party.
This is tentative translation of the “Post-Earthquake Equipment Integrity Assessment Guideline[Pre-Earthquake Plan and Post-Earthquake Inspections and Assessments]” © Japan Nuclear
Technology Institute, (2012). The authentic version of this material is the Japanese language version.
JANTI makes no warranty and assumes no responsibility for the accuracy or quality.
COPYRIGHT NOTICE: Permission to reproduce or translate the information contained in thisdocument may be obtained by writing to JANTI,4-2-3,Shiba Minato-ku,Tokyo 108-0014,JAPAN1

Introduction
At the “Structural Integrity Assessment for Nuclear Power Components experienced Niigata-ken Chuetsu-oki
Earthquake Committee” (SANE), which was established in the fall of 2007 following the Niigata-ken Chuetsu-oki
Earthquake, learned and experienced experts specializing in structural strength, inspection, earthquake resistance, etc.,
have been gathering with relevant parties from electric power companies and manufacturers to conduct integrity
assessments and reviews of important equipment at the Kashiwazaki-Kariwa Nuclear Power Station which was affectedby the earthquake. In order to allow relevant parties to widely share valuable findings obtained at this committee toprepare for future earthquakes, these findings were put together as the “Post-Earthquake Equipment Integrity
Assessment Guideline.”

In order to inspect the innumerable station equipment when an earthquake far exceeding design predictions occurs,
an inspection plan covering basic inspections (visual inspection and activation tests commonly conducted for eachequipment) and additional inspections (disassembling inspection / non-destructive tests) performed based on basic
inspections or seismic response analysis results must be created to clarify relevant laws and standards that needs to beobserved and skill levels required of inspectors and evaluators, and to undergo equipment inspections by precisely
predicting parts that may be damaged. Therefore, the SANE committee established an working group to deliberate
standards to be adhered to and qualifications of inspectors and evaluators. It also performs plastic strain assessment
along with nondestructive inspections and compiles the assessment method of, foundation bolt integrity assessment intoa guideline.

The Great Tohoku earthquake and tsunami of March 11, 2011, saw serious accidents at the TEPCO Fukushima
Daiichi Nuclear Power Station. Deliberations by this committee were mainly implemented prior to this earthquake andcover damage caused by earthquake motion, or felt earthquake. Accordingly, this guideline covers only damage caused
by earthquake motion.
We hope this guideline will be used to aid safe and stable nuclear power station operations, serving as reference fordeliberations of general industrial equipment inspection methods.
Finally, I would like to give a special thanks to the committee members, participants, and all the parties involved fortaking the time in their busy schedules to participate in the discussions and for their tremendous contributions.

March, 2012

JANTI SANE Committee
Chairman, Toshiharu Nomoto2

Post-Earthquake Equipment Integrity Assessment Guideline[Inspection Method: Pipes, Foundation Bolts] Contents

1.

Objective, scope

2.

Equipment inspection basic policy

3.

Basic inspection

4.

Additional inspection of pipes and foundation bolts

Appendix A: Plastic strain detection and measurement guideline (Index only)
Appendix B: Ultrasonic testing method for foundation bolts guideline (Index only)
Appendix C: Torque check testing method for foundation bolts guideline (Index only)
Appendix D: Ultrasonic testing method for pipe (elbow part) guideline (Index only)

Main Text
1.

Objective, scope

1.1 Objective
This guideline shows the scope of inspections for static equipment, especially piping andfoundation bolts, to be conducted by the nuclear power station when an earthquake occurs. The
inspection guideline shown here is the codification of applicable items to the nuclear power station
following the Niigata-ken Chuetsu-oki earthquake. The objective is to contribute to safe and stable
operation via use in integrity assessment plans for each nuclear power station.
1.2 Scope
Equipment and parts requiring post-earthquake inspection will be selected according to thepost-earthquake

equipment

integrity

assessment

guideline[pre-earthquake

plans,

andpost-earthquake inspection and assessment] (JANTI-SANE-G1). The inspection method for theselected equipment / parts will be determined according to the predicted damage type. When theinspection objective and scope coincide, the inspection method shown here may be applied.

2.

Equipment inspection basic policy
Equipment inspection will be classified as shown below for implementation.
(1) Basic inspection: Comprised of visual inspection and activation tests (function
verification, vibrational confirmation, leakage confirmation); performed for selected
equipment.
(2) Additional inspection: Comprised of non-destructive tests and plastic strain measurement;
performed based on basic inspection and seismic response analysis results. Includes
confirming the presence of abnormality check through open vessel inspection andmeasurement control equipment characteristic tests.

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The post-earthquake equipment integrity assessment guideline [pre-earthquake plans, andpost-earthquake inspection and assessment] (JANTI-SANE-G1) lists the conclusive approach on
post-earthquake equipment integrity assessment of the nuclear power station , pre-earthquake
plans, and post-earthquake response according to damage level.

3.

Basic inspection
3.1 Inspection method and decision standard
The equipment inspection procedures and decision standards utilize the regulation / policy
used for maintenance inspections (see Table 3-1), and adopt items found to be technologicallysound, to be stipulated for each SSC for inspection.

Table 3-1 List of sample decision standards for inspection / assessment methods (basic inspection)
Inspection method
Visual inspection

Leakage test
Activation test

Functionverification

Procedure / decision standard
・JSME Codes for Nuclear Power Generation Facilities: Rules on Maintenance VT-3
・JIS Z 3090 Visual testing method of fusion-welded joints
・NDIS 3414 Method of visual test
・NDIS 3415 Method of inspections for equipment and device
・JSME Codes for Nuclear Power Generation Facilities: Rules on Maintenance VT-2
・Regular testing performance values
・Procedures and decision standards of function / performance tests (regular operator
inspection)
・LBWR station operation maintenance policy (JEAC 4803)
・Procedures and decision standards of function / performance tests (regular operator
inspection)

3.2 Inspectors / evaluators
Inspectors / evaluators shall be workers possessing skills shown in Table 3-2.

Table 3-2 Skills required of inspectors / evaluators (basic inspection)
Inspection method
Visual inspection

4.

Skill
・Workers confirmed to have no vision problems through checks of close-up vision
required of non-destructive testing personnel as per JIS Z 2305 “Non-destructive
testing – Qualification and certification of personnel” utilized in NDIS 3413 “Methodof vision and color sight tests for non-destructive testing personnel.”・Workers with years of work experience, internal certification, record of education /testing reception, and other appropriate skills.

Additional inspection of pipes and foundation bolts
Knowledge based on the examples of the non-destructive inspection method and hardness

measurement method used after the Chuetsu-oki earthquake were organized to be able to be applied
to additional inspections of pipes and foundation bolds, which comprise the majority of static
equipment, when needed during post-earthquake structural integrity assessment. Testing guideline
details were compiled in Appendices A through D.

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4.1 Inspection method / decision standard(1)

The inspection method and decision standard for pipes are shown in Tables 4-1 through

4-5.
Table 4-1 Visual testing method and decision standard for pipes (additional inspection)
Item
Objective

Scope of inspection

Inspection method

Details
Confirm presence of warping or surface abnormalities on pipes.
Select systems where damage was discovered during basic inspections and systems withresults that do not satisfy allowable value during the seismic response analysis of seismic
resistance S class pipes that uses observed waves. These are subject to visual testing(VT).
Scope will cover all exteriors of each selected system. Thermal insulation will be
removed to perform VT for all scope items.
Based on IA-2523 VT-3 testing of the Rules on Maintenance (JSME S NA1-2004),
directly perform VT on the pipe surface.

Applicable regulation
Rules on Maintenance (JSME S NA1-2004)/ applied regulation
No pipe warping or other surface abnormalities.
Decision standard
If abnormality is detected, perform non-destructive testing according to abnormality type.
JSME S NA1-2004: Codes for Nuclear Power Generation Facilities: Rules on Maintenance (JSME)
Table 4-2 Liquid penetrant testing method and decision standard for pipes (additional inspection)
Item
Objective
Scope of inspection
Inspection method

Details
Confirm presence of cracks on external surface of pipes.
Select areas that do not satisfy allowable values from the seismic response analysis thatuses observed waves, for liquid penetrant testing (PT). Subject areas are within the scopeof the figure below.
Based on IA-2532 penetration testing of Rules on Maintenance (JSME S NA1-2004),
conduct PT on the external surface of pipes.

Applicable regulation
Rules on Maintenance (JSME S NA1-2004)/ applied regulation
No cracking-related indicators.
Decision standard
If cracking indicators are found, perform non-destructive testing such as UT.
JSME S NA1-2004: Codes for Nuclear Power Generation Facilities: Rules on Maintenance (JSME)
ｔ+20(1) Scope overview of PT on the elbow partｔ+20

All frequencies for ends and bend of the elbow part at
t+20mm scope (t: piping thickness)
ｔ+20

D(2) Scope overview of PT on the T part
Saddle part with same scope as header outside diameter (D)Ｌ(branch pipe side radius + branch straight pipe)
L: distance from header to branch pipe R

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t+20

t+20

(3) Scope overview of PT on the straight pipe
t+20mm from the support, weld and anchor scope where
PT is possible as shown in the figure on the right(t: pipe wall thickness)

Supportt+20

t+20

AnchorPipingｔ+20mmCenter of weld line

Table 4-3 Ultrasonic testing method and decision standard of pipe weld joints(additional inspection)
Item

Details

Objective

Check for cracks on the internal surface of pipe weld joints.
Select weld joints that do not satisfy the allowable value during the seismic response
Scope of inspection
analysis that uses observed waves. These are subject to ultrasonic testing (UT).
Perform UT on whole circumference of the internal surface of pipe weld joints from both
Inspection method
the axial and circumferential directions.
Applicable regulation Rules on Maintenance (JSME S NA1-2004)/ applied regulation JEAG4207-2004
Conform to the standard sensitivity stipulated in JEAG4207-2004. Create DAC arcs using
the skip points of the internal surface.
Standard sensitivity
1) Thickness under 25mm: 2S/8 & 6S/8
2) Thickness over 25mm: 3S/8 & 5S/8
Flaw detection sensitivity is as shown below:
Flaw detection
1) Manual flaw detection: more than twice the standard sensitivity (+6dB)
sensitivity2) Automatic flaw detection: standard sensitivity
Record level
Indicators exceeding DAC20%.
No indicators exceeding DAC20%.
When internal echo exceeding DAC20% is detected, assess the reflection source type.
Decision standard
Conduct additional testing and other non-destructive testing as needed for assessment.
When it is deemed to be an internal crack, discuss separately.
JSME S NA1-2004: Codes for Nuclear Power Generation Facilities: Rules on Maintenance (JSME)JEAG4207-2004: Ultrasonic testing policy for in-service inspection of LBWR nuclear power generationequipment (JEA)

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Table 4-4 Ultrasonic testing method and decision standard for pipe inspection (elbow part) (additional inspection)
Item
Objective
Scope of inspection
Inspection method

Details
Confirm presence of cracks on the internal surface of the pipe elbow part.
Select areas (elbow part) that do not satisfy allowable value during the seismic response
analysis that uses observed waves, for ultrasonic testing (UT). Scope of subject areas isshown in the figure below.
Perform UT on the internal surface of the pipe elbow part from the circumferential
direction.

Applicable regulation
Rules on Design and Construction (JSME S NC1-2005)/ applied regulation
Standard sensitivity is the sensitivity derived by adjusting the reflected echoes from theStandard sensitivity
internal slits of contrast testing parts to 80% of the value on the flaw detector screen.
Flaw detection sensitivity is as shown below:
Flaw detection
1) Manual flaw detection: more than twice the standard sensitivity (+6dB)
sensitivity2) Automatic flaw detection: standard sensitivity
Record level
Indicators standard sensitivity exceeding 40% of the value on the display device.
No indicators exceeding 40% of the value on the display device.
When internal echo exceeding 40% of the value on the display device is detected, assess
Decision standard
the reflection source type. Conduct additional testing and other non-destructive testing as
needed for assessment.
When it is deemed to be an internal crack, discuss separately.
JSME S NC1-2005: Codes for Nuclear Power Generation Facilities: Rules on Design andConstruction (JSME)(1) Scope overview of UT on the elbow part

４５°
９０°

探触子走査
probe
running test(2) Flaw detection method
Flaw detection in circumferential direction at
45° angle (lateral wave, 5MHz)

超音波探触子ultrasonic probe
配管
pipe

45°

7

Table 4-5 Surface hardness testing method and decision standard for pipes (additional inspection)
Item
Objective
Scope of inspection

Inspection method

Details
Confirm presence of plastic strain that will affect wear intensity.
Select areas that do not satisfy allowable values during the seismic response analysis thatuses observed waves. These will be subject to surface hardness testing. Select areas where
the maximum stress does not satisfy the allowable value (assessment parts) and where
impact is small (comparison parts) for testing.
Measurement areas of assessment and comparison parts shall be equal in diameter, form,material, manufacturing method, and direction.
A portable Vickers hardness instrument shall be used to measure surface hardness.
・T part (see fig. below)
・Straight pipe (see fig. below)

Applicable regulation
JIS Z 2244-2003/ applied regulation
Remove surface hardening layer.
Use #400 as final surface polishing conditions.
Use standard hardness testing piece to confirm a significant difference does not exist
Testing guideline
between standard hardness and measurement value, before and after testing.
Assume the score for each measurement area is 40 points to derive the average value andstandard deviation.
Find the maximum and minimum value for each assessment or comparison part. Compare
all maximum values and minimum values. Both the maximum and minimum values ofassessment parts must be less than those of comparison parts, or within the scope ofDecision standard
allowable dispersion (standard deviation). If decision standard is exceeded, conduct
overall assessment upon deliberation of measurement value dispersion, manufacturinghistory, and possibility of material non-uniformity.
JIS Z2244-2003: Vickers hardness testing method (JIS): hardness measurement area

SupportT partStraight pipe8(2) Inspection methods and decision standards equipment foundation bolts are shown in Tables 4-6
through 4-8.
Table 4-6 Visual testing method and decision standard for foundation bolts (additional inspection)
Item
Objective

Scope of inspection

Details
Confirm presence of warping, loosening, detachment or surface abnormalities onfoundation bolts.
Select systems where damage was discovered during basic inspections or systems withresults that do not satisfy allowable value during the seismic response analysis of seismic
resistance S class pipes that uses observed waves. These will be subject to visual testing(VT).
Directly perform VT on foundation bolts.

Inspection method
Applicable regulation
Rules on Maintenance (JSME S NA1-2004)/ applied regulation
No warping, loosening, detachment or surface abnormalities on foundation bolts.
Decision standard
If abnormalities are found, perform overall assessment through percussion testing, torquecheck testing and UT results.
JSME S NA1-2004: Codes for Nuclear Power Generation Facilities: Rules on Maintenance (JSME)
Table 4-7 Ultrasonic testing method and decision standard for foundation bolts(additional inspection)
Item
Objective
Scope of inspection

Details
Confirm presence of cracks on foundation bolt screws.
Select systems where damage was discovered during basic inspections or systems withresults that do not satisfy allowable value during the seismic response analysis of seismic
resistance S class pipes that uses observed waves. Foundation bolt screws will be subject
to UT.
Vertical deflection method (bottom echo method) used on foundation bolt screws.

Inspection method
Applicable regulation
Rules on Design and Construction (JSME S NC1-2005)/ applied regulation
Standard sensitivity is as shown below:
1) Screws on the ultrasonic echo incidence side: sensitivity derived by adjusting thereflected echoes from the bottom of sound parts to 80% of the value on the flaw
Standard sensitivity
detector screen.
2) Screws on the opposite of the ultrasonic echo incidence side: four times (+12dB) the
sensitivity derived by adjusting the reflected echoes from the bottom of sound parts to
80% of the value on the flaw detector screen.
Flaw detection
Flaw detection sensitivity will be the standard sensitivity + 6dB.
sensitivity
Record level
Indicators where echo height exceeds 5%.
No effective indicators where echo height exceeds 5%.
Decision standard
Discuss separately if effective indicators are confirmed.
JSME S NC1-2005: Codes for Nuclear Power Generation Facilities: Rules on Design andConstruction (JSME)

9

Table 4-8 Torque check testing method and decision standard for foundation bolts (additional inspection)
Item
Objective
Scope of inspection

Inspection method

Details
Confirm whether foundation bolts have lost fastening ability.
Select systems where damage was discovered during basic inspections or systems withresults that do not satisfy allowable value during the seismic response analysis of seismic
resistance S class pipes that uses observed waves. These will be subject to torque checktesting.
Tools (torque wrench) will be used for torque check testing (loosened side).
Torque value will be decided for each part using design requirement bolt axial force.

Applicable regulation/ applied regulation
Decision standard

Nuts not spinning during torque check testing.
If nuts spin, conduct overall assessment through the percussion test, VT and UT results.

4.2 Inspector / evaluator
Inspectors / evaluators shall be workers possessing skills shown in Table 4-9.
Table 4-9 Skills required of inspectors / evaluators (additional inspection)
Inspection method
Visual inspection

Non-destructive
testing

Pipe surface
hardness testing
Foundation bolt
torque test

Skill
・Workers confirmed to have no vision problems through checks of close-up vision
required of non-destructive testing personnel as per JIS Z 2305 “Non-destructive testing– Qualification and certification of personnel” utilized in NDIS 3413 “Method of visionand color sight tests for non-destructive testing personnel.”・Workers with years of work experience, internal certification, record of education /testing reception, and other appropriate skills.
Workers with qualifications and skills shown below for non-destructive testing:・Above Level 2 in JIS Z 2305 “on-destructive testing – Qualification and certificationof personnel”
・Skill level equivalent to above certification
・Workers with years of work experience, record of education / testing reception, andother appropriate skills.
・Workers with years of work experience, record of education / testing reception, andother appropriate skills.

10Appendix A: Plastic strain detection and measurement guideline (Index only)
1. Overview
1.1 Objective
1.2 Scope
1.3 Terms and abbreviations
1.4 Relevant regulations
2. Testing guideline
2.1 Assessed parts and compared parts
2.2 Polishing workers and measurers
2.3 Equipment used
2.4 Testing guideline
3. Decision-making and plastic strain measurement guideline
3.1 Plastic strain presence judgment
3.2 Plastic measurement
4. Record guideline
4.1 Recording procedures
4.2 Recorded contents
5. Assessment on earthquake impacts on plastic strain(Description)(Description.-1.1) Definitions of assessed parts, compared parts, measured part and measured area
(Description.-2.1) Ferrite steel annealed with low-temperature or normally(Description.-2.2) Austenite stainless steel treated with solution heat
(Description.-2.3) Materials with similar hardness(Description.-2.4) Polishing workers(Description.-2.5) Hardness measurers(Description.-2.6) Hardness measuring instruments(Description.-2.7) Inspection of repetition and errors(Description.-2.8) Work hardened layer confirmation method(Description.-2.9) Checking error pre/post-testing(Description.-2.10) Evidence for measured area of each measured part
(Description.-2.11) Space between measured areas(Description.-3.1) Decision method(Description.-4.1) Recording guideline(Description.-5.1) Assessment of earthquake impacts on plastic strain(Description.-5.2) Knowledge regarding equipment subject to testing11

Appendix B Ultrasonic testing method for foundation bolts guideline (Index only)
1. Overview
1.1 Objective
1.2 Scope of application
1.3 Terms and abbreviations
1.4 Relevant regulation
2. Testing guideline
2.1 Scope of testing
2.2 Testers and test evaluators
2.3 Materials used
2.3.1 Ultrasonic flaw detector
2.3.2 Probe
2.3.3 Contact medium
2.3.4 Ultrasonic flaw detector / probe correction
2.4 Testing guideline
2.4.1 Adjustment and confirmation of time axis and standard sensitivity
2.4.2 Testing
3. Decision guideline
3.1 Extracting ordered portions
3.2 Decision-making
4. Recording guideline
4.1 Recording procedure
4.2 Recorded contents(Description)(Description.-1.1) Impairment caused by earthquake(Description.-1.2) Guidelines stipulated in this Appendix(Description.-2.1) Adjusting standard sensitivity around terminal area
(Description.-3.1) Extracted standards(Description.-3.2) Impression impact(Description.-3.3) Determining whether impairment was caused by the earthquake

12Appendix C Torque check testing method for foundation bolts guideline (Index only)
1. Overview
1.1 Objective
1.2 Scope
1.3 Terms
2. Testing guideline
2.1 Materials used
2.2 Testing guideline
3. Decision guideline
4. Recording guideline

Appendix D Ultrasonic testing method for pipe (elbow part) guideline (Index only)
1. Overview
1.1 Objective
1.2 Scope
1.3 Terms and abbreviations
2. Testing guideline
2.1 Tested parts
2.2 Testers and Test evaluators
2.3 Materials used
3.4 Testing guideline
3. Decision guideline
3.1 Extracting ordered portions
3.2 Decision-making
4. Recording guideline
4.1 Recording procedure
4.2 Recorded contents

Post-Earthquake Equipment Integrity Assessment Guideline[[Inspection Method: Pipes, Foundation Bolts]]

Main Text

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Tel:+81-3-5440-3603

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