Steam Generator IntegrityAssessment GuidelinesRevision 2Non-Proprietary Version
1012987
Final Report, July 2006
EPRI Project ManagerE. Fuller
ELECTRIC POWER RESEARCH INSTITUTE3420 Hillview Avenue, Palo Alto, California 94304-1395 - PO Box 10412, Palo Alto, California 94303-0813 - USA
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ORGANIZATION(S) THAT PREPARED THIS DOCUMENT '1Li
Aptech Engineering
AREVA NP
Electric Power Research Institute
Steve Brown UTennessee Valley Authority
Westinghouse Electric Company LLC UUU
NOTE
For further information about EPRI, call the EPRI Customer Assistance Center at 800.313.3774 ore-mail [email protected]. .
Electric Power Research Institute and EPRI are registered service marks of the Electric PowerResearch Institute, Inc.
Copyright 0 2006 Electric Power Research Institute, Inc. All rights reserved. .
Li
CITATIONS
This report was prepared under the guidance of the Integrity Assessment Guidelines Committee.
Committee Members
Helen Cothron
James Begley
Steve Brown
Russell Cipolla
Robert Keating
David Ayres
Richard Coe
Joseph Mathew
William Moore
Stephen Leshnoff
Brad Corder
Alan Redpath
Daniel Mayes
Steve Swilley
Edward Blandford
Edward Fuller
Tennessee Valley Authority
AREVA NP
Consultant
Aptech Engineering
Westinghouse
Westinghouse
Southern California Edison
Omaha Public Power District
Southern Nuclear Operating Company
Exelon
Ameren UE
Progress Energy
Duke Power
EPRI
EPRI
EPRI
This report describes research sponsored by the Electric Power Research Institute (EPRI).
The report is a corporate document that should be cited in the literature in the following manner:
Steam Generator Integrity Assessment Guidelines: Revision 2. EPRI, Palo Alto, CA: 2006.1012987.
iii
REPORT SUMMARY
This report provides guidance for evaluating the condition of steam generator (SG) tubes basedon nondestructive examination (NDE) or in situ pressure testing. This integrity assessment isnormally performed during a reactor refueling outage. Nuclear power plant licensees who followthis document's guidelines will have satisfied their requirements for condition monitoring andoperational assessment as defined in the Nuclear Energy Institute (NEI) initiative, SteamGenerator Program Guidelines, NEI 97-06.
BackgroundDamage to steam generator tubing can impair its ability to adequately perform required safetyfunctions in terms of both structural integrity and leakage integrity. Therefore, assessing tubeintegrity is an important component of a steam generator program, which is required by NEI-97-06. This program establishes a framework for structuring and strengthening existing steamgenerator programs. The fundamental elements that are needed represent a balance of prevention,inspection, evaluation, repair, and leakage monitoring measures.
Objectives" To help licensees support implementation of NEI 97-06.
• To help licensees meet the integrity assessment performance criteria described in NEI 97-06.
* To define requirements and describe in detail implementation procedures for a successfulsteam generator integrity assessment.
ApproachAn ad-hoc committee of licensee experts and additional industry specialists developed theseintegrity assessment guidelines. This document presents common industry practices for integrityassessment that are achievable with current technology. Any revisions to these guidelines areimplemented through the Steam Generator Management Program consensus process, whichrequires adherence to a formal industry review, comment, and approval protocol. Interimguidance will be provided to the industry whenever necessary between guideline revisions.
ResultsThis document describes acceptable methods for degradation assessments, condition monitoring,operational assessments, and secondary-side assessments. Condition monitoring refers toassessing the status of steam generator tubes during an outage to ensure that they maintainedadequate safety margins for the previous operating period. Operational assessment is intended toensure that steam generator tubes will maintain adequate safety margins during the upcoming
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operating period. There are other acceptable methods for integrity assessment; however, theyrequire technical justification for their application.
This document is a major rewrite of Revision 1 of the integrity assessment guidelines. The reporthas been completely reorganized. There is more detail in each chapter, there are many fewerappendices, and much new material is included. A great deal of emphasis is placed on providingexamples of how to carry out the essential steps of an integrity assessment. Methods fordetermining probability of detection (POD) of flaws are provided, as are methods for estimatingflaw sizes and how large they might grow over an operating interval. There also is a new chapteron secondary-side integrity.
Since Revision I was published, there have been five occasions when interim guidance wasissued. These are as follows:
* Interim Guidance on New Degradation Mechanisms, August 31, 2001;
* Interim Guidance on Three Mile Island Tube Sever Event, August 18, 2003;
* Interim Guidance on Revised Structural Performance Criteria, SGMP-IG-05-001, January17, 2005;Ca
" Interim Guidance to Communicate Issuance ofNE1 97-06 R2 and Gaps Between Revision 2and Current Guidelines, SGMP-IG-05-002, October 10, 2005; and
* Interim Guidance Regarding Adverse Trend of Foreign Objects in Steam Generators,SGMP-IG-05-04, November 18, 2005.
This document incorporates guidance for these occasions, although the wording may be slightlyLdifferent. In any case, interim guidance is now superseded by this document.
EPRI PerspectiveNEI 97-06 requires condition monitoring and operational assessment of steam generator tubing.These integrity assessment guidelines provide a useful description of how steam generator tubingcan be shown to meet required performance criteria. Using a standard approach facilitatesacceptance and review by regulatory authorities.
This document reflects current industry practices and represents an acceptable method forintegrity assessment. Revisions can be expected as the industry accumulates experience with thisguideline.
KeywordsNuclear steam generatorsDegradation assessmentCondition monitoringOperational assessmentSecondary-side integrity assessmentIntegrity assessment
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CONTENTS
1 INTRODUCTION .................................................................................................................... 1-1
1.1 Objective ........................................................................................................................ 1-1
1.2 Scope ............................................................................................................................. 1-2
1.3 Basic Methodology of Steam Generator Integrity Assessment ...................................... 1-2
1.4 Com pliance Responsibilities .......................................................................................... 1-4
1.5 Contractor Oversight ...................................................................................................... 1-4
2 TUBE INTEGRITY CRITERIA ................................................................................................ 2-1
2.1 Introduction .................................................................................................................... 2-1
2.2 Structural Integrity Performance Criterion ...................................................................... 2-1
2.3 Leakage Integrity Performance Criteria .......................................................................... 2-3
2.4 Performance Acceptance Standards .............................................................................. 2-3
2.5 Discussion of Structural Margins and Bases .................................................................. 2-4
2.5.1 Assessment Factors ............................................................................................... 2-4
2.5.2 Burst Definition ....................................................................................................... 2-4
2.5.3 Collapse Definition .................................................................................................. 2-5
2.5.4 Limits on Yield Strength .......................................................................................... 2-5
2.6 Pressure Load Definitions ............................................................................................. 2-5
3 TUBE INTEGRITY ASSESSM ENT LIMITS ........................................................................... 3-1
3.1 Introduction .................................................................................................................... 3-1
3.2 Tube Integrity Limits ....................................................................................................... 3-1
3.2.1 Condition Monitoring Lim it ...................................................................................... 3-2
3.2.2 Operational Assessm ent Limit ................................................................................ 3-2
3.3 Material Properties ......................................................................................................... 3-6
3.4 Repair Limit .................................................................................................................... 3-6
3.5 Technical Specification Repair Limit .............................................................................. 3-6
3.6 Special Considerations for Tube Integrity Assessment .................................................. 3-7
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3.7 Determ ination of Structural Integrity Lim its .................................................................... 3-7
3.7.1 Tube Burst Event .................................................................................................... 3-7
3.7.2 Significant Contributing Loads ................................................................................ 3-7
3.7.3 Tube Collapse Event ............................................................................................ 3-11
4 NDE M EA SUREM ENT UNCERTA INTIES ............................................................................. 4-1
4.1 Introduction .................................................................................................................... 4-1
4.2 Probability of Detection ................................................................................................... 4-2
4.2.1 Requirements and Limitations for Tube Integrity Applications ............................... 4-2
4.2.2 PO D M odeling ........................................................................................................ 4-3
4.2.3 G LM Calculation of PO D and its Uncertainties ....................................................... 4-5
4.2.4 Experim ental Determ ination of System PO D ........................................................ 4-6
4.2.5 M odel-Assisted PO D Developm ent ........................................................................ 4-7
4.3 Sizing Requirements and Limitations for Tube Integrity Applications ............................. 4-8
4.4 Extension of Qualified NDE Techniques for Tube Integrity Applications ....................... 4-10
5 DEG RA DATIO N G ROW TH RATES .................................................................................... 5-1"
5.1 Introduction .................................................................................................................... 5-1
5.2 Background .................................................................................................................... 5-1
5.3 Data Evaluation Procedures ........................................................................................... 5-2
5.3.1 Conservative Estimate of the Growth Rate Distribution .................................... 5-3
5.3.2 Realistic Estim ate of the G rowth Rate Distribution ................................................. 5-3
5.4 Illustrations of Estimations of Actual Growth Rate Distributions ................................. 5-5
5.4.1 Exam ple 1: AVB W ear Plug on Sizing .................................................................... 5-5
5.4.2 Example 2: Axial PWSCC at Dented Intersections Plug-on-Sizing ........................ 5-7
5.4.3 Example 3: Axial ODSCC in OTSG Tubes Plug on Detection ............................... 5-9
5.5 Default G rowth Rate Distributions ................................................................................ 5-10
5.5.1 Axial Stress Corrosion Cracking ........................................................................... 5-10
5.5.2 Circum ferential Stress Corrosion Cracking .......................................................... 5-15
6 DEG RA DATIO N A SSESSM ENT ........................................................................................... 6-1
6.1 Introduction .................................................................................................................... 6-1
6.2 Purpose .......................................................................................................................... 6-1
6.3 Sources of Inform ation for Degradation Assessm ent ..................................................... 6-3
6.4 Identification of Potential Steam Generator Degradation Mechanisms .......................... 6-4
6.4.1 Degradation in Previously Plugged Tubes ............................................................. 6-4
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6.4.2 Types of Degradation .... ....................................................................................... 6-6
6.4.2.1 Intergranular Attack and Outside Diameter Stress Corrosion Cracking .......... 6-6
6.4.2.2 Primary Water Stress Corrosion Cracking and Intergranular Attack ............... 6-7
6.4.2.3 Tube Fretting and W ear .................................................................................. 6-7
6.4.2.4 Other W ear Dam age ....................................................................................... 6-7
6.4.2.5 Pitting .............................................................................................................. 6-7
6.4.2.6 High Cycle Fatigue ......................................................................................... 6-7
6.4.2.7 Im pingement ................................................................................................... 6-8
6.4.2.8 W astage/Thinning .......................................................................................... 6-8
*6.5 Identification of NDE Techniques .................................................................................... 6-9
6.6 Identification of Inspection Sam ple Plan ........................................................................ 6-9
6.7 Integrity Assessm ent and Repair Lim its ......................................................................... 6-9
6.8 Secondary Side Considerations ................................................................................... 6-10
6.9 Actions Upon Finding Unexpected Degradation .......................................................... 6-10
7 CONDITION M ONITORING .................................................................................................. 7-1
7.1 Introduction .................................................................................................................... 7-1
7.2 Condition M onitoring Evaluation Procedure ................................................................... 7-1
7.3 Structural Integrity Evaluation using Inspection Results ................................................ 7-2
7.3.1 Probabilities and Percentiles .................................................................................. 7-4
7.3.2 Arithm etic Strategy for Com bining Uncertainties .................................................... 7-4
7.3.3 Sim plified Statistical Strategy for Com bining Uncertainties .................................... 7-6
7.3.4 Monte Carlo Strategy for Com bining Uncertainties ................................................ 7-6
7.3.5 Strategy Comparison .............................................................................................. 7-6
7.3.5.1 Arithm etic Evaluation ...................................................................................... 7-7
7.3.5.2 Sim plified Statistical Evaluation ...................................................................... 7-8
7.3.5.3 M onte Carlo Evaluation ................................................................................... 7-9
7.4 Signal Am plitude Approaches to Structural Integrity .................................................... 7-11
7.5 Role of In Situ Pressure Testing ................................................................................... 7-12
7.6 Verification ................................................................................................................... 7-13
8 OPERATIONAL ASSESSM ENT ............................................................................................ 8-1
8.1 Introduction .................................................................................................................... 8-1
8.2 Projection of W orst Case Degraded Tube ...................................................................... 8-2
8.3 Fully Probabilistic Operational Assessm ent M ethods .................................................... 8-4
8.3.1 Repair on Detection ................................................................................................ 8-4
8.3.2 Repair on NDE Sizing ............................................................................................. 8-5
8.4 Repair on NDE Sizing: General Considerations ............................................................. 8-5
8.4.1 Arithm etic Strategy for Repair on NDE Sizing ........................................................ 8-9
8.4.2 Sim plified Statistical Strategy for Repair on NDE Sizing ........................................ 8-9
8.4.3 Mixed Arithmetic/Simplified Statistical Strategy for Repair on NDE Sizing ............ 8-9
8.4.4 Monte Carlo Strategy for Repair on NDE Sizing .................................................... 8-9
8.4.5 Strategy Com parison for Repair on NDE Sizing ................................................... 8-101 "
8.4.5.1 Example: Cold Leg Thinning at Drilled Tube Support Plates ........................ 8-10 I
8.4.5.2 Arithmetic Strategy ........................................................................................ 8-12
8.4.5.3 Mixed Arithmetic/Simplified Statistical/Monte Carlo Strategy ....................... 8-13
8.4.5.4 Sim plified Statistical Strategy ........................................................................ 8-14
8.4.5.5 M onte Carlo Strategy .................................................................................... 8-14
8.5 Repair on Detection General Considerations ............................................................... 8-15
8.5.1 Arithm etic Strategy for Repair on Detection ......................................................... 8-18
8.5.2 Sim plified Statistical Strategy for Repair on Detection ......................................... 8-18 L8.5.3 Mixed Arithmetic/ Simplified Statistical Strategy for Repair on Detection ............. 8-19
8.5.4 Monte Carlo Strategies for Repair on Detection ................................................... 8-19 L8.5.5 Com parison of Strategies for Repair on Detection ............................................... 8-19
8.5.5.1 Example Equation ......................................................................................... 8-19
8.5.5.2 Arithmetic Strategy ........................................................................................ 8-19
8.5.5.3 M ixed Arithm etic/Sim plified Statistical Strategy ............................................ 8-20 L8.5.5.4 Sim plified Statistical Strategy ........................................................................ 8-20
8.5.5.5 M onte Carlo Strategy .................................................................................... 8-21 L8.6 Signal Am plitude Based Operational Assessm ent ....................................................... 8-21
8.7 Verification ................................................................................................................... 8-23
9 PRIMARY-TO-SECONDARY LEAKAGE ASSESSMENT ..................................................... 9-1
9.1 Introduction .................................................................................................................... 9-1
9.2 Accident Induced Leakage ............................................................................................. 9-1
9.3 Operational Leakage ...................................................................................................... 9-1
9.4 Leak Rate Calculation Methodologies ........................................................................... 9-3
9.5 Validation of Leak Rate Equations ................................................................................. 9-7
9.6 Condition M onitoring Evaluation for Leakage Integrity ................................................... 9-9
9.7 Operational Assessm ent Evaluation for Leakage Integrity ........................................... 9-10
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9.8 Actions upon Failure to Meet Leakage Integrity Performance Criteria ......................... 9-12
10 MAINTENANCE OF SECONDARY SIDE INTEGRITY ...................................................... 10-1
10.1 Introduction ........................................................................................................... 10-1
10.2 Purpose ...................................................................................................................... 10-2
10.3 Secondary Side Assessm ents .................................................................................... 10-2
10.4 Secondary Side Cleaning ........................................................................................... 10-4
10.5 Secondary Side Visual Inspections ............................................................................ 10-4
10.6 Upper Internals Inspections ........................................................................................ 10-7
11 REPORTING ....................................................................................................................... 11-1
11.1 External Reporting ..................................................................................................... 11-1
11.2 Internal Reporting ....................................................................................................... 11-1
11.2.1 The Degradation Assessm ent Report ................................................................ 11-1
11.2.2 The Condition M onitoring Report ........................................................................ 11-2
11.2.3 The O perational Assessm ent Report ................................................................. 11-2
12 REQUIREM ENTS ............................................................................................................... 12-1
12.1 Introduction................................................................................................................. 12-1
12.2 Tube Integrity Criteria ............................................................................................ 12-1
12.3 Tube Integrity Assessm ent Lim its .............................................................................. 12-2
12.4 NDE M easurem ent Uncertainties ............................................................................... 12-3
12.5 Degradation G rowth Rates ......................................................................................... 12-3
12.6 Degradation Assessm ent ....................................... .................................................... 12-3
12.7 Condition M onitoring .................................................................................................. 12-6
12.8 Operational Assessm ent ....................................................................................... 12-6
12.9 Prim ary-to-Secondary Leakage Assessm ent ........................................................ 12-7
12.10 M aintenance of SG Secondary Side Integrity ........................................................ 12-10
12.11 Reporting ................................................................................................................ 12-12
13 G LOSSARY ........................................................................................................................ 13-1
14 LIST OF ABBREVIATIONS AND ACRONYMS ................................................................. 14-1
15 REFERENCES ................................................................................................................... 15-1
A APPENDIX A: INDUSTRY TECHNICAL BASES FOR STRUCTURAL INTEGRITYASSESSM ENT ......................................................................................................................... A-1
A.1 Introduction ................................................................................................................... A-1
A.2 Definition of Burst .......................................................................................................... A-2
A.2.1 Burst Condition ...................................................................................................... A-2
A.2.2 Technical Discussion ............................................................................................ A-2
A.2.3 Application - Condition M onitoring ........................................................................ A-3
A.3 Deterministic Structural Performance Criterion Pressure Loading Definition ............... A-3
A.3.1 Background .......................................................................................................... A-3
A.3.2 Statem ent of Structural Perform ance .................................................................... A-3
A.3.3 Definitions ............................................................................................................. A-4
A.3.4 Technical Discussion ............................................................................................ A-5
A.3.5 Limits on Yield Strength ........................................................................................ A-6
A.4 ASM E Code Review ..................................................................................................... A-7
A.4.1 M inim um W all Requirem ents ................................................................................ A-7
A.4.2 Primary Loads from Accidents Events .................................................................. A-8 L
A.4.2.1 ASM E Section III Appendix F Considerations ............................................... A-8
A.4.3 Secondary Loads from Accident Events ............................................................. A-12
A.4.3.1 Definition of Secondary Loads ..................................................................... A-12
A.4.3.2 Code Practice .............................................................................................. A-13
A.4.4 Sum mary of Code Considerations ...................................................................... A-13
A.5 Historical Perspective ................................................................................................. A-14
A.5.1 Regulatory Perspective ....................................................................................... A-14
A.5.2 Application of Industry Definition ......................................................................... A-15
A.5.2.1 Original Design ............................................................................................ A-15
A.5.2.2 Condition Monitoring .................................................................................... A-15
A.5.2.3 Validation of Industry Definition ................................................................... A-16 LA.6 Assessment of Contributing Loads ............................................................................. A-17
A.6.1 Primary Loads ..................................................................................................... A-18A.6.2 Axial Membrane Loads in OTSG Tubing............................A-18
A.6.3 Axial Mem brane Loads in RSG Tubing ............................................................ A-19
A.6.4 Treatm ent of Axial Therm al Loads ................................................................. A-1 9
A.7 Allowable Structural Lim its .......................................................................................... A-21
A.7.1 Tube Burst Condition .......................................................................................... A-21
A.7.2 Plastic Collapse Under Tension and Bending ..................................................... A-22
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A.7.3 Circum ferential Degradation ............................................................................... A-22
A.7.4 Axial Degradation ............. ................................................................................... A-23
A.8 Sum m ary and Conclusions ......................................................................................... A-24
A.9 References .................................................................................................................. A-25
B APPENDIX B: MODEL-ASSISTED POD DEVELOPMENT ............................................ B-1
B.1 M odel-Assisted PO D (M APO D) ............................................................................... B-1
B.1.1 Ahat M odeling ................................................................................................... B-1
B.1.2 Noise-Dependent Structural PO D M odeling .................................... .................... B-6
B.1.2.1 Ahat (S/N) M odeling ...................................................................................... B-7
B.1.2 2 M onte Carlo Ahat (S/N) Sim ulation ............................................................... B-7
B.1.2.3 Incorporating Hum an Factor or Personnel Effects ........................................ B-9
B.1.2.4 Illustrating the Dependency of PO D on (S/N) .......................................... B-11
B.1.2.5 PO D M odel Prediction and Validation ......................................................... B-12
B.1.2.6 Applications ................................................................................................. B-14
B.2 References .................................................................................................................. B-19
C APPENDIX C: EXAMPLES OF CONDITION.MONITORING AND OPERATIONAL
ASSESSM ENT LIM IT DETERM INATIO N ........................................................................... C-1
C.A Axial Cracking Exam ples .............................................................................................. C-2
C.1.1 Exam ple of Freespan, Through-wall Axial Crack .................................................. C-2
C.1.2 Condition M onitoring Lim it Using Arithm etic M ethod ............................................ C-3
C.1.3 Condition Monitoring Limit Using Simplified Statistical Method ........................ C-4
C.1.4 G rowth .................................................................................................................. C-6C.1.5 M onte Carlo Analysis ............................................................................................ C-6
C.2 Circum ferential Cracking Exam ples ....................................................................... C-10
C.2.1 Circumferential Cracking with Restricted Lateral Tube Motion, Pressure andBending Loads ............................................................................................................... C -1 0
C .2.2 Input Param eters ............................................................................................ C-I 1
C .2.3 G overning Equations .......................................................................................... C-12
C.2.4 Structurally Significant External Loads ............................................................... C-15
C.2.5 Pressure O nly ..................................................................................................... C -16
C.2.5.1 Calculation of the Structural Lim it ................................................................ C-17
C.2.5.3 Sim plified Statistical Analysis, Pressure O nly ......................................... C-1 9
C.2.5.4 M onte Carlo Analysis, Pressure O nly .......................................................... C-21
C .2.6 Pressure Plus External Bending and Axial Loads ............................................... C-23
C.2.6.1 Calculation of the Structural Limit, Pressure Plus Bending & AxialLoads ........................................................................................................................ C-24
C.2.6.2 Condition Monitoring Limit, Pressure Plus Bending & Axial Loads ............. C-26
C.2.6.3 Arithmetic Method, Pressure Plus Bending & Axial Loads .......................... C-27
C.2.6.4 Simplified Statistical Analysis, Pressure Plus Bending & Axial Loads ........ C-28
C.2.6.5 Monte Carlo Analysis, Pressure Plus Bending & Axial Loads ..................... C-31
C.2.7 Conclusions ........................................................................................................ C-32 1
C.3 Volum etric Degradation Exam ples ............................................................................. C-33
C.3.1 Example of Uniform 3600 Thinning Over a Given Axial Length .......................... C-33
C.3.2 Structural Lim it .................................................................................................... C-33
C.3.3 Condition M onitoring Lim it .................................................................................. C-34
C.3.4 G rowth ................................................................................................................ C-35
C.3.5 M onte Carlo Analysis .......................................................................................... C-38
C.4 References ................................................................................................................. C-41
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LIST OF FIGURES
Figure 1-1 Steam Generator RCS Pressure Boundary Assessment; Condition Monitoringand O perational Assessm ent ............................................................................................. 1-3
Figure 2-1 SIPC Im plem entation Logic ...................................................................................... 2-2
Figure 3-1 Condition Monitoring Elements of Tube Integrity Assessment ................................. 3-3
Figure 3-2 Operational Assessment Elements of Tube Integrity (Repair on Sizing) .................. 3-4
Figure 3-3 Operational Assessment Elements of Tube Integrity (Repair on Detection) ............ 3-5
Figure 3-4 Logic for Screening Contributing Loads ................................................................... 3-9
Figure 4-1 Generating a POD Model Using Binary Hit-Miss Data ............................................. 4-4
Figure 4-2 Different POD Models Resulting from the Same Hit-Miss Data ............................... 4-4
Figure 4-3 GLM Workbook for Calculating POD and POD Uncertainties .................................. 4-5
Figure 4-4 Accounting for Data Analyst Uncertainty using a GLM Weighted AverageP O D ................................................................................................................................... 4 -7
Figure 4-5 Model-Assisted Example POD Calculations Using Data for VolumetricDegradation at Tube Support Plate Center and Edges ...................................................... 4-8
Figure 4-6 Regression Plot Format Used for Determining NDE Sizing Errors - Cold LegT hinning D ata ..................................................................................................................... 4-9
Figure 5-1 Global Average Growth rate of Maximum Depth as Voltage Threshold ofAcceptable Sizing Data is Increased .................................................................................. 5-5
Figure 5-2 Comparison of NDE Measured Growth Rates, Actual Physical Growth Ratesand Computer Simulation of NDE Measured Growth Rates for Wear Depth Growth ........ 5-7
Figure 5-3 Distribution of NDE Measured Average Depth Growth Rates of PWSCCIndications Left In Service under an ARC .................................. 5-8
Figure 5-4 Distribution of NDE Measured Length Growth Rates of PWSCC IndicationsLeft In Service under an ARC ............................................................................................ 5-8
Figure 5-5 Comparison of NDE Measured Growth Rates, Actual Physical Growth Ratesand Computer Simulation of NDE Measured Growth Rates for Axial PWSCC ................ 5-11
Figure 5-6 Deceleration Factor for ODSCC and PWSCC Growth Rates Compared to6 11°F ................................................................................................................................ 5-12
Figure 5-7 Comparison of NDE Measured Growth Rate Distribution with ComputerSimulation Result of NDE Measured Growth Rate Distribution, OTSG AxialO D S C C /IG A ..................................................................................................................... 5-13
Figure 5-8 Comparison of NDE Measured Growth Rate Distribution with Best EstimatePhysical Growth Rates Distribution, OTSG Axial ODSCC/IGA ........................................ 5-14
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Figure 5-9 Cumulative Distributions of Average Depth Growth Rates of AxialODSCC/IGA (curve on the left is a best estimate distribution, others include NDEsizing uncertainties) ........................................................................................................ 5-15
Figure 6-1 Recirculating Steam Generator Degradation Mechanisms ...................................... 6-2
Figure 6-2 Once Through Steam Generator Degradation Mechanisms .................................... 6-3
Figure 7-1 Condition Monitoring Structural Limit Curves for Axial PWSCC Per ETSS96703.1 at 4155 psi Using Three Strategies for Combining Uncertainties ....................... 7-10
Figure 7-2 Condition Monitoring Plot for Freespan Axial ODSCC/IGA in OTSG Tubing at4 050 psi ............................................................................................................................ 7-12
Figure 8-1 Cumulative Distribution of Cold Leg Thinning Depth Growth Rate NDEMeasurements, Computer Simulation of NDE Measurements, and Best EstimateGrowth Rate Distribution .................................................................................................. 8-12
Figure 8-2 Signal Amplitude-Based Operational Assessment for Freespan AxialODSCC/IGA at OTSG Plants Voltage Illustrated ............................................................. 8-22
Figure 9-1 Calculated and Measured Leak Rates for Axial Cracks in Alloy 600 Tubing atNormal Operating Conditions ............................................................................................. 9-8
Figure 10-1 Process of Recording, Monitoring, and Assessing Data ....................................... 10-3
Figure 10-2 Contingency Planning for Secondary Side Inspection with no PlannedPrimary Side Inspection ................................................................................................... 10-8
Figure A-1 SIPC Implementation Logic ..................................................................................... A-4
Figure B-1 Ahat POD Modelling ................................................................................................ B-3
Figure B-2 ExcelTM Implementation of Ahat POD Modeling for Cold-Leg Thinning ETSSD ata ................................................................................................................................... B 4
Figure B-3 ExcelTM Implementation of Ahat POD Modeling for Cold-Leg Thinning ETSSD ata ................................................................................................................................... B -5
Figure B4 ExcelTM Implementation of Ahat POD Modeling for Cold-Leg Thinning ETSSD ata ................................................................................................................................... B -6
Figure B-5 Monte Carlo Simulation of Ahat (S/N) Data ............................................................ B-8
Figure B-6 Modelling Data Analyst Human Factor Effects using a (S/N) DependentR eporting Probability ......................................................................................................... B-9
Figure B-7 Monte Carlo Generated Noise Dependent Structural POD Model .................... B-1 1
Figure B-8 Cumulative Noise Distributions Used for Noise-Dependent Monte Carlo PODS im ulations ...................................................................................................................... B -12
Figure B-9 Monte Carlo Simulated Noise-Dependent Structural Detection ProbabilitiesShowing the Effects of Increasing and Decreasing Noise .............................................. B-13
Figure B-10 Monte Carlo Predicted POD Compared with Technique Limit and WeightedAverage POD for one the Performance Demonstration Datasets ................................... B-14
Figure B-11 Kolmogorov-Smirnov Comparison of Two Noise Distributions ....................... B-1 5
Figure B-12 Kolmogorov-Smirnov Comparison of Two Noise Distributions ....................... B-1 6Figure B-13 Simulation Logic for Deriving Effective POD .................................................. B-1 7
Figure B-14 Simulation Outputs for +Pt Confirmation ............................................................. B-18 L8Figure B-15 Comparison of Effective POD with Bobbin and +Pt coil PODs (+Pt
C onfirm ation) ................................................................................................................... B-18
Xvi
Figure C-1 Burst Pressure as a Function of Critical Crack Length for the Three Methods ....... C-9
Figure C-2 Burst pressure as a function of PDA for circumferentially cracked tubes [CI] ...... C-13
Figure C-3 Distribution of Growth for Uniform Thinning .......................................................... C-37
Figure C-4 Comparison of CM solutions for a burst pressure of 4.473 ksi ............................. C-39
Figure C-5 Distribution of simulated burst pressures for a sample depth and length ............. C-40
LIST OF TABLES
Table 4-1 Steam Generator Tube Wall Degradation ............................................. 4-2
Table 4-2 Correlation Coefficient, r*, at 95% confidence level for a positive correlation[19] ................................................................................................................................... 4 -10
Table 4-3 Examples of Extended Applicability of Qualified Techniques .................................. 4-11
Table 7-1 Condition Monitoring Uncertainty Treatment for Structural Integrity .......................... 7-5
Table 8-1 Operational Assessment Uncertainty Treatment for Structural Integrity forRepair on NDE Sizing ....................................................................................................... 8-6
Table 8-2 Operational Assessment Uncertainty Treatment for Structural Integrity forRepair on Detection ........................................................................................................ 8-16
Table A-1 Alloy 600 Typical Properties - Mean Values ............................................................ A-9
Table A-2 Typical Differential Pressures for NSSS Designs ................................................... A-17
Table B-1 Example Monte Carlo POD Simulator Output Data ........................................... B-10
Table C-1 Summary of Critical FDA Results for Circumferential Crack Example ................... C-32
Table C-2 Structural Limit Parameter hsL Solutions for Several L Values ............................... C-34
Table C-3 Relational and Material Uncertainties Calculated at the 95 th Percentile ................. C-35
Table C-4 Postulated Distribution of Growth of Uniform Thinning Indications forOperational Assessment Calculations (OD = 0.875, t = 0.050) ....................................... C-36
xix
1INTRODUCTION
1.1 Objective
These guidelines present requirements and implementation procedures for meeting the objectivesof steam generator tube integrity assessments including:
1. Identification and characterization of degradation forms within steam generators that requireassessment,
2. Application of appropriate NDE technology, consistent with the expected degradation and inaccordance with the EPRI Steam Generator Examination Guidelines [1].
3. Application of integrity assessment methods, consistent with the expected degradation andrequired safety factor, for use in evaluating integrity at the end of an inspection interval andto ensure integrity during the subsequent inspection interval.
Successful implementation of the above objectives will help ensure that steam generator integritywill be maintained for each degradation form during operation and applicable design basisaccidents.
Licensees should use this document to demonstrate the condition of their steam generatorsrelative to performance criteria used for condition monitoring and operational assessment asdefined in the NEI initiative, Steam Generator Program Guidelines NEI 97-06 [2].
1-1
Introduction
1.2 Scope
As required by NEI 97-06, this document offers guidance and requirements for the evaluationmethods, margin, and uncertainty considerations used to determine tube integrity. It alsoprovides guidance for performing steam generator degradation assessment (DA), conditionmonitoring (CM), operational assessment (OA), and secondary side assessment. Assessment ofsteam generator tube integrity requires an evaluation of both burst and leakage throughout anoperational plant cycle. Information on how to carry out these assessments is provided in thebody of this document with supplemental examples in the appendices. Other approaches may beused with technical justification.
1.3 Basic Methodology of Steam Generator Integrity Assessment
This section summarizes the details of steam generator integrity assessment. This assessmentapplies to steam generator components which are part of the primary pressure boundary (e.g.,tubing, tube plugs, sleeves and other repairs). It also applies to foreign objects and secondaryside structural supports (e.g., tube support plates) that may, if severely degraded, compromisepressure-retaining components of the steam generator.
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Introduction
Figure 1-1Steam Generator RCS Pressure Boundary Assessment; Condition Monitoring andOperational Assessment
1-3
Introduction
1.4 Compliance Responsibilities
This document presents a general approach and examples for demonstrating steam generator tubeintegrity. Plant specific programs should consider plant design, materials, steam generatorcorrosion experience, and operating philosophy. Performing the assessments herein will helpplant personnel understand what inspections and repairs are necessary and the appropriate lengthof operation between inspections. To meet this goal, an effective corporate policy andmonitoring program are essential and should be based on the following:
1.5 Contractor Oversight
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2TUBE INTEGRITY CRITERIA
2.1 Introduction
This chapter presents analysis margins and acceptance criteria for structural integrity andthrough-wall leakage associated with degraded steam generator tubing.
2.2 Structural Integrity Performance Criterion
The SIPC provides the margins for tube integrity against tube burst or collapse. The structuralintegrity performance criterion is:
2-1
Tube Integrity Criteria
Figure 2-1SIPC Implementation Logic
2-2 U
Tube Integritj, Criteria
2.3 Leakage Integrity Performance Criteria
The leakage integrity performance criteria provide requirements for both operational andaccident leakage.
2.4 Performance Acceptance Standards
The performance acceptance standards for assessing tube integrity to the structural integrity andaccident leakage performance criteria apply to both condition monitoring and operationalassessments. The acceptance standard for structural integrity is:
The acceptance standard for accident leakage integrity is:
2-3
Tube Integrity Criteria
2.5 Discussion of Structural Margins and Bases
2.5.1 Assessment Factors
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2-4
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Tube Integrity Criteria
2.5.3 Collapse Definition
2.5.4 Limits on Yield Strength
2.6 Pressure Load Definitions
2-5
Tube Integrity Criteria
Normal steady-state full power operation as defined in NEI 97-06 [2], and discussed in AppendixA, is:
The conditions existing during MODE 1 operation at the maximum steady state reactorpower as defined in the design or equipment specification. Changes in design parameterssuch as plugging or sleeving levels, primary or secondary modifications, or Thot should beassessed and their effects on differential pressure included if significant.
The limiting accident pressure differential is the maximum or largest pressure differential acrossthe tube wall for the design basis accidents (Service Levels C and D). For most plants, this is thepressure differential during a main steam line break. Apart from pressure loading, othercontributing loads that can occur during the postulated accidents shall be evaluated to determineif these loads contribute significantly to tube burst. Such loads are discussed in Section 2.5.1,Section 3.7.2, and in Appendix A.
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3TUBE INTEGRITY ASSESSMENT LIMITS
3.1 Introduction
This chapter presents the general requirements for establishing the tube integrity and repair limitsassociated with steam generator tubing, such that the tube integrity performance criteria and theperformance acceptance standards defined in Chapter 2 are satisfied during operation. Tubeintegrity limits are defined for each degradation mechanism.
3.2 Tube Integrity Limits
3-1
Tube hItegrity Assessment Limits
3.2.1 Condition Monitoring Limit
Condition monitoring is the assessment of the current state of the steam generator tubing, and isperformed at the conclusion of each steam generator inspection. The purpose of conditionmonitoring is to confirm that both the structural integrity and accident-induced leakageperformance criteria were satisfied during the past inspection interval.
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3.2.2 Operational Assessment Limit
An operational assessment is a forward-looking prediction of the steam generator tube conditionsat the next inspection.
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Tube Integrity Assessment Limits
Figure 3-1Condition Monitoring Elements of Tube Integrity Assessment
3-3
Tube Integiity Assessment Limits
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Tube Integrity Assessment Limits
Figure 3-3Operational Assessment Elements of Tube Integrity(Repair on Detection)
3-5
Tube Integrity Assessment Limits
3.3 Material Properties
3.4 Repair Limit
3.5 Technical Specification Repair Limit
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3.6 Special Considerations for Tube Integrity Assessment
3.7 Determination of Structural Integrity Limits
3.7.1 Tube Burst Event
3.7.2 Significant Contributing Loads
3-7
Tube hutegrity Assessment Limits
3-8
Tube Integrity Assessment Limits
Figure 3-4Logic for Screening Contributing Loads
3-9
Tube Integrity Assessment Limits
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Tube Integrity Assessment Limits
3.7.3 Tube Collapse Event
3-11
4NDE MEASUREMENT UNCERTAINTIES
4.1 Introduction
This chapter addresses NDE system performance measures and their uncertainties associatedwith tube bundle examination for tube integrity applications. Two aspects of performance areconsidered: 1) degradation detection, quantified by Probability of Detection (POD), and 2)degradation sizing, quantified by linear correlations of true-versus-measured values of structuralquantities of interest, such as length and depth of degradation.
4-1
NDE Measurement Uncertainties
Table 4-1Steam Generator Tube Wall Degradation
4.2 Probability of Detection
4.2.1 Requirements and Limitations for Tube Integrity Applications
4-2
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NDE Measurement Uncertainties
4.2.2 POD Modeling
A POD model is a functional measure of the ability of an NDE system to detect degradati6n.
4-3
NDE Measutrement Uncertainties
Figure 4-1Generating a POD Model Using Binary Hit-Miss Data
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Figure 4-2Different POD Models Resulting from the Same Hit-Miss Data
4-4
NDE Measurement Uncertainties
4.2.3 GLM Calculation of POD and its Uncertainties
4-5
a-
NDE Measurement Uncertainties
4.2.4 Experimental Determination of System POD
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4-6
NDE Measurement Uncertainties
Figure 4-3Accounting for Data Analyst Uncertainty using a GLM Weighted Average POD
4.2.5 Model-Assisted POD Development
4-7
NDE Measurement Uncertainties
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4.3 Sizing Requirements and Limitations for Tube Integrity Applications
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NDE Measurement Uncertainties
Figure 4-5Regression Plot Format Used for Determining NDE Sizing Errors - Cold Leg Thinning Data
4-9
NDE Measurement Uncertainties
Table 4-2Correlation Coefficient, r*, at 95% confidence level for a positive correlation [19]
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4.4 Extension of Qualified NDE Techniques for Tube Integrity Applications
4-10
NDE Measurement Uncertainties
Table 4-3Examples of Extended Applicability of Qualified Techniques
4-11
5DEGRADATION GROWTH RATES
5.1 Introduction
In this chapter methods are presented to determine degradation growth rates from NDEinspection information. This chapter also provides specific growth rate information from industryservice experience that may be used when plant-specific data are limited.
5.2 Background
5-1
Degradation Growth Rates
5.3 Data Evaluation Procedures
The following procedures can be used to characterize distributions of growth rates for use inOperational Assessments. Two methods are presented. The first method is a simplified approachthat provides a conservative estimate for growth since it includes sizing uncertainties. In somesituations, this method may result in a very conservative value for growth rate distribution, inwhich case a second, more refined method, may be used to give a more realistic estimate forgrowth rate by explicitly accounting for sizing uncertainties.
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5-3
Degradation Growth Rates
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Degradation Growth Rates
Measured Average Growth Rates per Cycle versus Voltage Threshold,OTSG Freespan ODSCC
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5.4 Illustrations of Estimations of Actual Growth Rate Distributions
Three examples of estimating actual physical growth rates from NDE measurements ofdegradation growth are presented below. The first two examples are for plug on sizing repairscenarios and the third is for a plug-on-detection degradation mechanism.
5.4.1 Example 1: A VB Wear Plug on Sizing
5-5
Degradation Growth Rates
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Degradation Growth Rates
Figure 5-2Comparison of NDE Measured Growth Rates, Actual Physical Growth Rates and ComputerSimulation of NDE Measured Growth Rates for Wear Depth Growth.
5.4.2 Example 2: Axial PWSCC at Dented Intersections Plug-on-Sizing
5-7
Degradation Growth Rates
Figure 5-3Distribution of NDE Measured Average Depth Growth Rates of PWSCC Indications Left InService under an ARC
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5.4.3 Example 3: Axial ODSCC in OTSG Tubes Plug on Detection
5-9
Degradation Growth Rates
5.5 Default Growth Rate Distributions
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Figure 5-5Comparison of NDE Measured Growth Rates, Actual Physical Growth Rates and ComputerSimulation of NDE Measured Growth Rates for Axial PWSCC
5-11
Degradation Growth Rates
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5-13
Degradation Growth Rates
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Figure 5-9Cumulative Distributions of Average Depth Growth Rates of Axial ODSCCIIGA(curve on the left is a best estimate distribution, others include NDE sizing uncertainties)
5.5.2 Circumferential Stress Corrosion Cracking
5-15
6DEGRADATION ASSESSMENT
6.1 Introduction
Degradation assessment is the process of identifying and documenting existing and potentialdegradation in planning for an upcoming outage, including inspection plans and related actionsfor the primary and secondary sides of the steam generator.
6.2 Purpose
The overall purpose of the degradation assessment is to ensure that appropriate inspections areperformed during the upcoming outage, and that the requisite information for integrityassessment is provided.
6-1
a.-
Degradation Assessment
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Figure 6-1Recirculating Steam Generator Degradation Mechanisms
6-2
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Figure 6-2Once Through Steam Generator Degradation Mechanisms
6.3 Sources of Information for Degradation Assessment
6-3
Degradation Assessment
6.4 Identification of Potential Steam Generator Degradation Mechanisms
6.4.1 Degradation in Previously Plugged Tubes
6-4
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Degradation Assessment
6-5
Degradation Assessment
6.4.2 Types of Degradation
6.4.2.1 Intergranular Attack and Outside Diameter Stress Corrosion Cracking
6-6
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Degradation Assessment
6.4.2.2 Primary Water Stress Corrosion Cracking and Intergranular Attack
6.4.2.3 Tube Fretting and Wear
6.4.2.4 Other Wear Damage
6.4.2.5 Pitting
6.4.2.6 High Cycle Fatigue
6-7
Degradation Assessment
6.4.2.7 Impingement
6.4.2.8 Wastage/Thinning
6-8
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Degradation Assessment
6.5 Identification of NDE Techniques
6.6 Identification of Inspection Sample Plan
6.7 Integrity Assessment and Repair Limits
6-9
Degradation Assessment
6.8 Secondary Side Considerations
6.9 Actions Upon Finding Unexpected Degradation
6-10
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7CONDITION MONITORING
7.1 Introduction
Condition monitoring (CM) involves the evaluation of inspection results at the end of theinspection interval to determine the state of the steam generator tubing for the most recent periodof operation relative to structural and leakage integrity performance criteria. This chapterprovides guidance on performing structural assessments.
7.2 Condition Monitoring Evaluation Procedure
7-1
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Condition Monitoring
7.3 Structural Integrity Evaluation using Inspection Results
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Condition Monitoring
7-3
Condition Monitoring
7.3.1 Probabilities and Percentiles
7.3.2 Arithmetic Strategy for Combining Uncertainties
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Condition Monitoring
Table 7-1
Condition Monitoring Uncertainty Treatment for Structural Integrity
7-5
Condition Monitoring
7.3.3 Simplified Statistical Strategy for Combining Uncertainties
7.3.4 Monte Carlo Strategy for Combining Uncertainties
7.3.5 Strategy Comparison
7-6
Condition Monitoring
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7-7
Condition Monitoring
7.3.5.2 Simplified Statistical Evaluation
7-8
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Condition Monitoring
7.3.5.3 Monte Carlo Evaluation
7-9
I-
Condition Monitoring
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Figure 7-1Condition Monitoring Structural Limit Curves for Axial PWSCC Per ETSS 96703.1 at 4155psi Using Three Strategies for Combining Uncertainties
7-10
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Condition Monitoring
7.4 Signal Amplitude Approaches to Structural Integrity
7-11
Condition Monitoring
Figure 7-2Condition Monitoring Plot for Freespan Axial ODSCCIIGA in OTSG Tubing at 4050 psi
7.5 Role of In Situ Pressure Testing
7-12
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7.6 Verification
7-13
8OPERATIONAL ASSESSMENT
8.1 Introduction
Operational Assessment (OA) involves projecting the condition of the SG tubes to the time ofthe next scheduled inspection outage and determining their acceptability relative to the tubeintegrity performance criteria of NEI 97-06 [2].
8-1
4.-
Operational Assessment
8.2 Projection of Worst Case Degraded Tube
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8-2
Operational Assessment
8-3
IOperational Assessment
8.3 Fully Probabilistic Operational Assessment Methods
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Operational Assessment
8.3.2 Repair on NDE Sizing
8.4 Repair on NDE Sizing: General Considerations
8-5
Operational Assessment
Table 8-1Operational Assessment Uncertainty Treatment for Structural Integrity for Repair onNDE Sizing
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8-6
Operational Assessment
Table 8-1 (continued)Operational Assessment Uncertainty Treatment for Structural Integrity for Repair onNDE Sizing
8-7
Operational Assessment
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8-8
Operational Assessment
8.4.1 Arithmetic Strategy for Repair on NDE Sizing
8.4.2 Simplified Statistical Strategy for Repair on NDE Sizing
8.4.3 Mixed Arithmetic/Simplified Statistical Strategy for Repair on NDE Sizing
8.4.4 Monte Carlo Strategy for Repair on NDE Sizing
8-9
Operational Assessment
8.4.5 Strategy Comparison for Repair on NDE Sizing
8.4.5.1 Example: Cold Leg Thinning at Drilled Tube Support Plates
8-10
I LOperational Assessment
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Operational Assessment
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Figure 8-1Cumulative Distribution of Cold Leg Thinning Depth Growth Rate NDE Measurements,Computer Simulation of NDE Measurements, and Best Estimate Growth Rate Distribution
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8-12
Operational Assessment
8.4.5.3 Mixed Arithmetic/Simplified Statistical/Monte Carlo Strategy
8-13
Operational Assessment
8.4.5.4 Simplified Statistical Strategy
8.4.5.5 Monte Carlo Strategy
8-14
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8.5 Repair on Detection General Considerations
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Operational Assessment
Table 8-2Operational Assessment Uncertainty Treatment for Structural Integrity for Repairon Detection
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Operational Assessment
Table 8-2 (continued)Operational Assessment Uncertainty Treatment for Structural Integrity for Repairon Detection
8-17
Operational Assessment
8.5.1 Arithmetic Strategy for Repair on Detection
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8-18
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8.5.3 Mixed Arithmetic/ Simplified Statistical Strategy for Repair on Detection
8.5.4 Monte Carlo Strategies for Repair on Detection
8.5.5 Comparison of Strategies for Repair on Detection
8.5.5.1 Example Equation
8.5.5.2 Arithmetic Strategy
8-19
Operational Assessment
8.5.5.3 Mixed Arithmetic/Simplified Statistical Strategy
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Operational Assessment
8.5.5.5 Monte Carlo Strategy
8.6 Signal Amplitude Based Operational Assessment
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8-21
Operational Assessment
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Signal Amplitude-Based Operational Assessment for Freespan Axial ODSCCIIGA at OTSGPlants Voltage Illustrated
8-22
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Operational Assessment
8.7 Verification
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8-23
9PRIMARY-TO-SECONDARY LEAKAGE ASSESSMENT
9.1 Introduction
This chapter provides requirements for primary-to-secondary leakage assessment and documentsmethods to calculate leakage.
9.2 Accident Induced Leakage
9.3 Operational Leakage
9-1
*1
Primary-to-Secondary Leakage Assessment
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9-2
Prima y-to-Seconda)' Leakage Assessment
9.4 Leak Rate Calculation Methodologies
9-3
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Primary-to-Secondary Leakage Assessment
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Primaqy-to-Secondary Leakage Assessment
9-5
Prirnay-to-Secondary Leak-age Assessment
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9-6
Primamy-to-Secondawy Leakage Assessment
9.5 Validation of Leak Rate Equations
9-7
Primary-to-Secondary Leakage Assessment
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Figure 9-1Calculated and Measured Leak Rates for Axial Cracks in Alloy 600 Tubing at NormalOperating Conditions
9-8
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Primai,-to-Secondaiy Leakage Assessment
9.6 Condition Monitoring Evaluation for Leakage Integrity
9-9
Prima9y-Io-Secondaly Leakage Assessment
9.7 Operational Assessment Evaluation for Leakage Integrity
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Priinai-to-Secondaiy Leakage Assessment
9-11
Primaqy-to-Secondary Leakage Assessment
9.8 Actions upon Failure to Meet Leakage Integrity Performance Criteria
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9-12
10MAINTENANCE OF SECONDARY SIDE INTEGRITY
10.1 Introduction
10-1
Maintenance of Secondaty Side Integrity
10.2 Purpose
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Maintenance of Secondawy Side Integrity
Figure 10-1Process of Recording, Monitoring, and Assessing Data
10-3
Maintenance ofSecondany Side integrity
10.4 Secondary Side Cleaning
10.5 Secondary Side Visual Inspections
10-4
Maintenance of Secondary Side Integrity
10-5
Maintenance of Secondary Side Integrity
ii
10-6
Maintenance of Secondary Side Integrity
10.6 Upper Internals Inspections
10-7
Maintenance of Secondagy Side hItegrity
Figure 10-2Contingency Planning for Secondary Side Inspection with no Planned Primary Side Inspection
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11REPORTING
11.1 External Reporting
Required reporting to the NRC is addressed in each licensee's technical specification and in NEI97-06. The NRC report includes the results of the condition monitoring performed during a SGinspection.
Required reporting to the industry is addressed in NEI 97-06. It is important the licensees shareexperiences with the industry in a timely manner through the SGMP and/or the INPO OEprocess. If a performance criterion is exceeded or if a new industry degradation mechanism isidentified, this information should be sent to appropriate SGMP representatives as soon aspossible via e-mail so that lessons learned can be disseminated quickly to the industry. Allappropriate tables in the EPRI Steam Generator Database shall be completed within 120 daysafter startup.
11.2 Internal Reporting
The reporting discussed in this section is not meant to cover all required internal reporting ordocumentation. This section is concerned with required reporting for integrity assessments.Refer to other EPRI Guidelines for additional internal reporting requirements.
11.2.1 The Degradation Assessment Report
I-I
Reporting
11.2.2 The Condition Monitoring Report
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11.2.3 The Operational Assessment Report
11-2
12REQUIREMENTS
12.1 Introduction
12.2 Tube Integrity Criteria
12-1
Requirements
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12.3 Tube Integrity Assessment Limits HLHLL
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12-2
Requirements
12.4 NDE Measurement Uncertainties
12.5 Degradation Growth Rates
12.6 Degradation Assessment
12-3
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12-4
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12-5
Requirements
12.7 Condition Monitoring
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12-6
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12-8
Requirements
12-9
Requirements
12.10 Maintenance of SG Secondary Side Integrity
12-10
Requirements
12-11
Requirements
12.11 Reporting
12-12
13GLOSSARY
13-1
Glossary
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13-2
Glossary
13-3
Glossary
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13-5
14LIST OF ABBREVIATIONS AND ACRONYMS
AILPC Accident-Induced Leakage Performance Criterion
ARC Alternate Repair Criteria
ASL Axial Secondary Loads
ASME American Society of Mechanical Engineers
AVB Anti-Vibration Bar
AVT All Volatile Treatment
BOC Beginning of Cycle
BP Burst Pressure
B&W Babcock and Wilcox
CAF Corrosion-Assisted Fatigue (High Cycle Fatigue)
CDF Cumulative Distribution Function
CE Combustion Engineering
CEOG Combustion Engineering Owners' Group
CFR Code of Federal Regulations
CLT Cold Leg Thinning
CM Condition Monitoring
CMTR Certified Mill Test Report
DA Degradation Assessment
ECT Eddy Current Testing
EDF Empirical Distribution Function
EFPY Equivalent Full-Power Years
EOC End of Cycle
EPRI Electric Power Research Institute
ETSS Examination Technique Specification Sheet
FDA Fractional Degraded Area
FLB Feed Line Break
FME Foreign Material Exclusion
FOSAR Foreign Object Search and Retrieval
FS Free Span
FSAR Final Safety Analysis Report
14-1
List ofAbbreviations andAcronyms
GDC General Design Criteria
GLM Generalized Linear Modeling
GPD Gallons Per Day
GR Growth Rate
IAGL Integrity Assessment Guidelines
ICC Intergranular Cellular Corrosion
ID Inside Diameter
IGA Intergranular Attack
IDIGA Inside Diameter Intergranular Attack
IGSCC Intergranular Stress Corrosion Cracking
INPO Institute for Nuclear Power Operations
ISI In-Service Inspection
LAPD Limiting Accident Pressure Differential
LCO Limiting Condition Operation
LOCA Loss of Coolant AccidentLR Leak Rate --'LTL Lower Tolerance Limit
MAPOD Model-Assisted Probability of Detection
MD Maximum Depth
MSLB Main Steam Line Break
NDE Nondestructive Examination L,NEI Nuclear Energy Institute
NMP NDE Measurement Parameter iNOP Normal Operating Pressure
NOPD Normal Operating Pressure Differential
NRC United States Nuclear Regulatory Commission
NSSS Nuclear Steam Supply System
OA Operational Assessment
OD Outside Diameter
ODSCC Outside Diameter Stress Corrosion Cracking
OE Operating Experience
01 Operating Interval
OTSG Once Through Steam Generator
PDA Percent Degraded Area
Pdf Probability Density Function
PICEP Pipe Crack Evaluation Program (a computer program)
14-2
List ofAbbreviations and Acronyms
PL
POB
POD
POL
PWR
PWSCC
RCPB
RFC
RG
RPC
RSG
SF
SG
SGDD
SGMP
SGPB
SGTR
SIPC
SL
SLB
SR
SRP
SSE
STP
S/N
TRM
TS
TSP
TSPC
TSPE
TW
UTS
W
Primary Load
Probability of Burst
Probability of Detection
Probability of Leak
Pressurized Water Reactor
Primary Water Stress Corrosion Cracking
Reactor Coolant Pressure Boundary
Retirement for Cause
Regulatory Guide
Rotating Pancake Coil
Recirculating Steam Generators
Safety Factor
Steam Generator
Steam Generator Degradation Database
Steam Generator Management Program
Steam Generator Pressure Boundary
Steam Generator Tube Rupture
Structural Integrity Performance Criterion
Structural Limit
Steam Line Break
Stability Ratio
Standard Review Plan
Safe Shutdown Earthquake
Standard Temperature and Pressure (60'F, 760 mm Hg)
Signal-to-Noise Ratio
Technical Requirements Manual
Tubesheet
Tube Support Plate
Tube Support Plate Center
Tube Support Plate Edge
Through Wall
Upper Tubesheet (in OTSGs)
Westinghouse
14-3
15REFERENCES
1. Pressurized Water Reactor Steam Generator Examination Guidelines: Revision 6,Requirements. EPRI, Palo Alto, CA: 2002. 1003138.
2. "Steam Generator Program Guidelines," Nuclear Energy Institute NEI 97-06, Revision 2,Nuclear Energy Institute, Washington, DC (May 2005).
3. Steam Generator Management Program Administrative Procedures, Revision 1, EPRI, PaloAlto, CA: 2004. 1011274.
4. Steam Generator Degradation Specific Management Flaw Handbook, EPRI, Palo Alto, CA:2001. 1001191
5. Impacts of the Structural Integrity Peiformance Criterion on Steam Generator Tube IntegrityEvahlations, EPRI, Palo Alto, CA: 2004. TR-1009541
6. Annis. C., "Measuring the Reliability of Nondestructive Evaluation Systems." AmericanInstitute of Aeronautics and Astronautics, AIAA-94-1399-CP. 1994.
7. Statistical Engineering Webpage, http://wwv.stastisticalemiineering.com
8. Myers, R.H. and D. Montgomery. "A Tutorial on Generalized Linear Models." Journal ofQuality Technology, Vol. 29, No. 3, July 1997.
9. Meyers, R., et al., "Generalized Linear Models With Applications to Engineering and theSciences," John Wiley and Sons, New York, New York, USA, 2002.
10. Dobson, A. "An Introduction to Generalized Linear Models." Chapman & Hall/CRC 2002.
11. SG-SGDA-02-51, "Tube Integrity Tools Manual," Westinghouse Electric Company,Madison, PA, USA: December, 2002.
12. "Flaw Handbook Tools Theory Manual," Prepared for EPRI by Westinghouse ElectricCompany, Madison, PA, USA: July 2005.
13. Integrity Assessment Examples Manual, EPRI, Palo Alto, CA: 2006. 1012986.
14. "Recombinant DNA - A New Approach to Evahlating the Effects of Plant Noise on NDEDetection and Sizing Capabilities," EPRI SG NDE Conference, July 2002.
15. "DQV on Eddyview - Where We Have Been and Where are We Going?, "EPRI SG NDEConference, July 2004.
16. SG-SGDA-06-02, "Users Manual - Crystal Ball Program for Adjusting NDE PerformanceTest PODs for Alternate Noise Distributions, Westinghouse Electric Company, Madison PA,USA - December 2005.
17. Users Manual - rystal Ball Program for Predicting NDE System POD, EPRI, Palo Alto:2006. 1012988.
15-1
References
18. Brown, S. D., "NDE System Sizing Error Verification," Letter Report dated November,2005.
19. Beyer, W.H "Handbook of Tables for Probability and Statistics", CRC Publications 1966.
20. "Degradation Growth Rates in OTSG Tubing," AREVA/FANP Document 51-5022969-00,September 2003.
21. "Assessment of Current Understanding of Mechanisms of Initiation, Arrest and Reinitiationof Stress Corrosion Cracks in PWR Steam Generator Tubing," NUREG/CR-5752, ANL-99/4, February 2000.
22. "Sequoyah Nuclear Plant U1CI 0 Steam Generator Inspection Results," TVA Presentation toNRC Staff, April 25, 2000.
23. Three Mile Island Plugged Tube Severance: A Study of Damage Mechanisms, EPRI, PaloAlto, CA: May 2003: 1008438.
24. "Rapidly Propagating Fatigue Cracks in Steam Generator Tubes," NRC Bulletin No. 88-02,United States Nuclear Regulatory Commission, Washington, DC, February 5, 1988.
25. Steam Generator In Situ Pressure Test Guidelines, EPRI, Palo Alto, CA: 2003. 1007904Rev. 2.
26. EPRI Steam Generator Management Program, "ECT Examination Technique SpecificationSheets," www.EPRlq.comrL
27. "Correlation of Burst Pressure with Plus Point Voltage and Length for OTSG AxialODSCC," Framatome Calculation Note 32-5030334-00, August 2003.
28. Technical Basis for Steam Generator Tube Integrity Performance Acceptance Standards,EPRI, Palo Alto, CA: 2006. 1012984.
29. "Alternative Radiological Source Terms for Evaluating Design Basis Accidents at NuclearPower Reactors," Regulatory Guide 1. 183, United States Nuclear regulatory Commission,Washington, DC, July 2000.
30. PWR Primary-To-Secondary Leak Guidelines-Revision 3, EPRI, Palo Alto, CA: 2004.1008219
31. Depth Based Structural Analysis Methods for SG Circumferential Indications, EPRI, PaloAlto, CA: 1997. 107197-P1
32. Steam Generator Tubing Burst Testing and Leak Rate Testing Guidelines, EPRI, Palo Alto,CA: 2002. 1006783
33. PICEP: Pipe Crack Evaltation Program, EPRI, Palo Alto, CA: 1987. NP-3596-SR, Rev. I
34. Steam Generator Tube Leakage Experiments and PICEP Calculations, EPRI, Palo Alto, CA:1990. NP-6897-L
35. Depth Based Structural Analysis Methods for SG Circumferential Indications, EPRI, PaloAlto, CA: 1997. 107197-PI
36. Ductile Fracture Handbook, Vohlme 1: Circumferential Throughwall Cracks, EPRI, PaloAlto, CA: 1989. NP-6301-DVI
15-2
References
37. Ductile Fracture Handbook. Vohlme 2, EPRI, Palo Alto, CA: 1990. NP-6301-DV2
38. Duffy, A. R., Eiber, R. J. and Maxey, W. A., "Recent Work on Flaw Behavior in PressureVessels," Proceedings of the Symposium on Fracture Toughness Concepts for WeldableStructural Steel, UKAEA, Chapman and Hall Ltd., Risley, April 1969.
39. "Pressure and Leak-Rate Tests and Models for Predicting Failure of Flawed Steam GeneratorTubes," NUREG/CR-6664, ANL 99/23, August 2000.
40. Steam Generator Foreign Object Task Force Review Material. EPRI, Palo Alto, CA: 2006.1012921.
15-3
AAPPENDIX A:STRUCTURAL
INDUSTRY TECHNICAL BASES FORINTEGRITY ASSESSMENT
A.1 Introduction
A-1
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.2 Definition of Burst
A.2.1 Burst Condition
A.2.2 Technical Discussion
A-2
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.2.3 Application - Condition Monitoring
A.3 Deterministic Structural Performance Criterion Pressure LoadingDefinition
A.3.1 Background
A.3.2 Statement of Structural Performance
A-3
Appendir A: hIdustry Technical Bases for Structural Integrity Assessment
Figure A-I1SIPC Implementation LogicL
A.3.3 Definitions
A-4
Appendix A: Industiy Technical Bases for Structural Integrity Assessment
LA.3.4 Technical Discussion
LLL
A-5
Appendix A: Indusiy Technical Bases for Structural Integrity Assessment
L
LLL
A.3.5 Limits on Yield Strength L
LLLL
A-6
Appendix A: Industs, Technical Bases for Structural Integrity Assessment
A.4 ASME Code Review
A.4.1 Minimum Wall Requirements
A-7
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.4.2 Primary Loads from Accidents Events
A.4.2.1 ASME Section III Appendix F Considerations
A-8
L4Li
Li
Lj
UjLL
LL
L
Appendix A: Industry Technical Bases for Structural Integrity Assessment
Table A-1
L Alloy 600 Typical Properties - Mean Values
LLLL
A-9
Appendix A: Industry Technical Bases for Structural Integrity Assessment
LLLLLLLL
LU
LA-10
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A-1I
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.4.3 Secondary Loads from Accident Events
A.4.3.1 Definition of Secondary Loads LJ
I,,J
L
L7L
L•L•
LL•L
A-12 L
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.4.3.2 Code Practice
A.4.4 Summary of Code Considerations
A-13
Appendix A: Industiy Technical Bases for Structural Integrity Assessment
A.5 Historical PerspectiveL
A.5.1 Regulatory Perspective
IL4
L
LLLU 'L
L
A-14
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.5.2 Application of Industry Definition
A.5.2.1 Original Design
A.5.2.2 Condition Monitoring
A-15
Appendix A: Industry Technical Bases for Structural Integrity Assessment
I I
L
LL
A.5.2.3 Validation of Industry Definition LLLLLL
L
L
A-16
Appendix A: lndustiy Technical Bases for Structural Integrity Assessment
Table A-2Typical Differential Pressures for NSSS Designs
A.6 Assessment of Contributing Loads
A-17
Appendix A: Industry Technical Bases for Strlctural Integrity Assessment
A.6.1 Primary Loads
A.6.2 Axial Membrane Loads in OTSG Tubing
A-18
L.
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.6.3 Axial Membrane Loads in RSG Tubing
A.6.4 Treatment of Axial Thermal Loads
A-19
L-a
Appendix A: Industry Technical Bases for Structural Integrity Assessment,
b 4
L•
L;
L
A-2L
Appendix A: Industy Technical Bases for Structural Integrity Assessment
A.7 Allowable Structural Limits
A. 7.1 Tube Burst Condition
L
L
L
L
U
L
L
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.7.2 Plastic Collapse Under Tension and Bending
A. 7.3 Circumferential Degradation
A-22
LL
LLLLU
LL
LL
L
L•
Appendix A: Industry Technical Bases for Structural Integrity Assessment
Axial Degradation
A-23
Appendix A: Industry Technical Bases for Structural Integrity Assessment
A.8 Summary and Conclusions
L
L
L
LLiLi
Li
LA-24L
Appendix A: Industiy Technical Bases for Structural Integrity Assessment
A.9 References
Al Title 10 to the Code of Federal Regulations, Part 50.
A2 "Steam Generator Program Guidelines," Nuclear Energy Institute NEI 97-06, Revision 1,Nuclear Energy Institute, Washington, DC (January 2001).
A3 Testimony of James Knight before the Atomic Safety and Licensing Board, U.S. NuclearRegulatory Commission, Washington, DC (January 1975).
A4 Draft Regulatory Guide 1.121, "Bases for Plugging Degraded PWR Steam GeneratorTubes," U.S. Nuclear Regulatory Commission, Washington, DC (August 1976).
A5 ASME Boiler and Pressure Vessel Code, Section III, Division 1, Subsection NB, "Class IComponents," 2004 Edition.
A6 "Burst Pressure Correlation for Steam Generator Tubes with Through-Wall Axial Cracks",EPRI TR-105505, Final Report, October 1997.
A7 "Safety Evaluation Report Related to the Preliminary Design of the Standard ReferenceSystem RESAR-414," NUREG-0491, Docket Number STN 50-572, United States NuclearRegulatory Commission, November 1978.
A8 "Steam Generator In Situ Pressure Test Guidelines," EPRI Report TR-107904-R2, ElectricPower Research Institute, Palo Alto, CA (August 2003).
A9 "Guidelines for Steam Generator Tube Section Removal, Test and Examination", EPRITR-016743-V4R1 Final Report, December 1997.
A10 Steam Generator Tubing Burst Testing and Leak Rate Testing Guidelines, EPRI, Palo Alto,
CA: 2002. 1006783
Al l Draft Regulatory Guide DG-1074, "Steam Generator Tube Integrity," March 1998.
A12 "Impacts of the Structural Integrity Performance Criterion on Steam Generator TubeIntegrity Evaluations," EPRI TR- 1009541, (November 2004).
A13 ASME Boiler and Pressure Vessel Code, Section XI, Rules for the Inservice Inspection ofNuclear Power Plant Components," 2004 Edition.
A14 "Evaluation of Flaws in Austenitic Steel Piping," EPRI NP-4690-SR, Special Report, (July1986).
A15 Cipolla, R. C., D. A. Scarth, G. M. Wilkowski, and V. A. Zilberstein, "Technical Basis forProposed Revision to Acceptance Criteria for ASME Section XI Pipe Flaw Evaluation,"
A-25
11Appendix A: Industry Technical Bases for Structural Integrity Assessment
PVP Vol. 422, 2001 ASME Pressure Vessel and Piping Conference, Atlanta, Georgia, (July23-26, 2001).
A16 Testimony of Raymond Maccary before the Atomic Safety and Licensing Appeal Board,U.S. Nuclear Regulatory Commission, Washington, DC (January 1976).
A17 Atomic Safety and Licensing Board, LBP-75-27, U.S. Nuclear Regulatory Commission,Washington, DC (May 1, 1975).
A18 Regulatory Guide 1.160, "Assessing and Managing Risk Before Maintenance Activities atNuclear Power Plants," U.S. Nuclear Regulatory Commission, Washington, DC -
A19 Costa, D., "Treatment of Tube Axial Thermal Loads," Report No. 51-5021407-01,AREVA. j
A20 NEI letter to NRC (S.J. Collins), "Industry Steam Generator Program Initiative", datedDecember 17, 1998. i1
L
L
A-26
BAPPENDIX B: MODEL-ASSISTED PODDEVELOPMENT
B.1 Model-Assisted POD (MAPOD)
B.1.1 Ahat Modeling
B-1
t-J
Appendix B: Model-Assisted POD Development
LL
L
B-2
L
Appendix B: Model-Assisted POD Development
Figure B-1Ahat POD Modelling
B-3
Appendix B: Model-Assisted POD Development
L
LjLL7Li
Figure B-2Excel TM Implementation of Ahat POD Modeling for Cold-Leg Thinning ETSS Data
B-4
U
Appendix B: Model-Assisted POD Development
Figure B-3ExceITM Implementation of Ahat POD Modeling for Cold-Leg Thinning ETSS Data
B-5
Appendix B: Model-Assisted POD Development
I .;
L
Figure B-4Excel TM Implementation of Ahat POD Modeling for Cold-Leg Thinning ETSS Data
B. 1.2 Noise-Dependent Structural POD Modeling
B-6
Appendix B: Model-Assisted POD Development
B.1.2.1 Ahat (S/N) Modeling
B.1.2 2 Monte Carlo Ahat (S/N) Simulation
B-7
Appendix B: Model-Assisted POD Development
Figure B-5 %JMonte Carlo Simulation of Ahat (SIN) DataL
LiL
LLL
B-8
L
Appendix B: Model-Assisted POD Development
B.1.2.3 Incorporating Human Factor or Personnel Effects
Figure B-6Modelling Data Analyst Human Factor Effects using a (SIN) Dependent ReportingProbability
B-9
Appendix B: Model-Assisted POD Development
Table B-1Example Monte Carlo POD Simulator Output Data
B-1O
L
LU
LLLUU
LU
U
U
U
Appendix B: Model-Assisted POD Development
Figure B-7Monte Carlo Generated Noise Dependent Structural POD Model
B.1.2.4 Illustrating the Dependency of POD on (SIN)
B-1I
Appendix B: Model-Assisted POD Development
Figure B-8Cumulative Noise Distributions Used for Noise-Dependent Monte Carlo POD Simulations
HU
H
B.1.2.5 POD Model Prediction and Validation
B-12
L
Appendix B: Model-Assisted POD Development
Figure B-9Monte Carlo Simulated Noise-Dependent Structural Detection Probabilities Showing theEffects of Increasing and Decreasing Noise
B-13
Appendix B: Model-Assisted POD Development
'I
Figure B-10Monte Carlo Predicted POD Compared with Technique Limit and Weighted Average PODfor one the Performance Demonstration Datasets
B.1.2.6 Applications
1.0
0.8
CU.0
EC.,
0.6
0.4
LLLLLL
L
L~i
0.2
0.00.0 0.1 0.2 0.3 0.4 0.5
Noise Amplitude, volts
0.6
B-14
ULUUULULU
Appendix B: Model-Assisted POD Development
Figure B-11Kolmogorov-Smirnov Comparison of Two Noise Distributions
B-15
Appendix B: Model-Assisted POD Development
U
UU
Figure B-12Kolmogorov-Smirnov Comparison of Two Noise Distributions U
UUU
UUUU
B-16
U
LLU
LLLU
LLLIiUUL
Appendix B: Model-Assisted POD Development
Figure B-13Simulation Logic for Deriving Effective POD
B-17
Appendix B: Model-Assisted POD Development
Simulation Outputs
for +Pt Confirmation
Figure B-14 L
Figure Bo15 (Comparison of Effective POD with Bobbin and +Pt coil PODs (+Pt Confirmation)
B-18
Appendix B: Model-Assisted POD Development
B.2 References
BI Berens, A.P. and P.W. Hovey, "Evaluation of NDE Reliability Characterization," AFWAL-TR-81-4160, Vol. 1, Air Force Wright Aeronautical Laboratories, WPAFB, OH, December1981
B2 Berens, A.P. and P.W. Hovey, "Flaw Detection Reliability Criteria, Volume I - Methodsand Results" AFWAL-TR-84-4022, Vol. 1, Air Force Wright Aeronautical Laboratories,WPAFB, OH, April 1984
B3 Berens, A.P., "NDE Reliability Data Analysis," ASM Metals Handbook Volume 17Nondestructive Evaluation and Quality Control, 9"' Ed., American Society of MetalsInternational, Materials Park, OH, 1989
B4 MIL-HDBK-1823, "Department of Defense Handbook - Nondestructive Evaluation SystemReliability Assessment," April 1999
B5 Berens, A.P. "Probability of Detection (POD) Analysis for the Advanced retirement forCause (RFC)/Engine Structural Integrity Program (ENSIP) Nondestructive Evaluation(NDE) System- Volume 1: POD Analysis " AFRL-ML-WP-TR-2001-4010, Air ForceResearch Laboratory, WPAFB, OH, January, 2000
B6 Berens, A.P. "Probability of Detection (POD) Analysis for the Advanced retirement forCause (RFC)/Engine Structural Integrity Program (ENSIP) Nondestructive Evaluation(NDE) System - Volume 2: POD Users Manual" AFRL-ML-WP-TR-2001-401 1, Air ForceResearch Laboratory, WPAFB, OH, January, 2000
B7 "Monte Carlo POD Simulator Users Guide" Aptech Engineering Services Report, Preparedunder Task 6b of the EPRI Tools for Tube Integrity Assessment Program, Draft dated July,2004
B8 "Guidelines for NDE and Destructive Exam Data Acceptability for NDE POD and SizingPerformance Evaluations" Westinghouse/Aptech Engineering Report prepared under Task 3of EPRI Tools for Tube Integrity Assessment Program, July 2003
B-19
CAPPENDIX C: EXAMPLES OF CONDITIONMONITORING AND OPERATIONAL ASSESSMENTLIMIT DETERMINATION
C-1
Appendix C:- Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.1 Axial Cracking Examples
C. 1. 1 Example of Freespan, Through-wall Axial Crack
La
La
La
La
LLL
LL
C-2
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C. 1.2 Condition Monitoring Limit Using Arithmetic Method
C-3
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
L
&-j
C. 1.3 Condition Monitoring Limit Using Simplified Statistical Method
LLLL
Li
LLLL
C-4
L
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C-5
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.1.4 Growth
C.1.5 Monte Carlo Analysis
C-6
I-
I-
L
iiKKKKKKLK
L
Appendix C: Examples of Condition Monitoring and Operational Assessment LinitDetermination
C-7
Appendix C:- Examples of Condition Monitoring and Operational Assessment LimitDetermination
U.
Ls
LLLLi
L
LILLLLIU
C-8 L
L
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
Figure C-1Burst Pressure as a Function of Critical Crack Length for the Three Methods
C-9
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2 Circumferential Cracking Examples
C.2.1 Circumferential Cracking with Restricted Lateral Tube Motion, Pressure andBending Loads
C-10
Appendix C: Examples of Condition Monitoring and Operational Assessment Linit
Determination
C.2.2 Input Parameters
C-1I
L..
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.3 Governing Equations
U
L
LL
C-12
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
Figure C-2Burst pressure as a function of PDA for circumferentially cracked tubes [Cl]
C-13
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
L
LL
L
L
L
CJ
Li
C-14
L
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.4 Structurally Significant External Loads
C-15
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.5 Pressure Only
LLiiLUUU
C-16
L
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.5.1 Calculation of the Structural Limit
C-17
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.5.2 Arithmetic Method, Pressure Only
C-18
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.5.3 Simplified Statistical Analysis, Pressure Only
C-19
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
LLLLL
LLL
C-20
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.5.4 Monte Carlo Analysis, Pressure Only
C-21
Appendix C: Examples of Condition Monitoring and OperationalAssessment LimitDetermination
LIiLUUUU
L
U
C-22
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.6 Pressure Plus External Bending and Axial Loads
C-23
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.6.1 Calculation of the Structural Limit, Pressure Plus Bending & Axial Loads
L
L
LIL
LC-24
L
LLU
Appendix C: Examples of Condition Monitoring and Opelational Assessment LimitDetermination
C-25
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.6.2 Condition Monitoring Limit, Pressure Plus Bending & Axial Loads
C-26
L Appendix C.: Examples of Condition Monitoring and Operational Assessment Limit
LO DeterminationC.2.6.3 Arithmetic Method, Pressure Plus Bending & Axial Loads
L
LL
LL
LLL I
C-27LL
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.6.4 Simplified Statistical Analysis, Pressure Plus Bending & Axial Loads LL'LLL
LiLL
C-28
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C-29
Appendir C: Examples of Condition Monitoring and Operational Assessment LimitDetermlination
L.
U
U
4.
LL
L
C-30
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
C.2.6.5 Monte Carlo Analysis, Pressure Plus Bending & Axial Loads
C-31
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
i !
U
UC.2.7 Conclusions
Table C-1Summary of Critical FDA Results for Circumferential Crack Example
LAUI
C-32
Appendix C: Examples of Condition Monitoring and Operational Assessment Limit
L ~C.3 Volumetric Degradation Examples D emnto
L C.3.1 Example of Uniform 360 0 Thinning Over a Given Axial Length
L C.3.2 Structural Limit
LL
LL
LLLL
LLL
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
Table C-2Structural Limit Parameter hsL Solutions for Several L Values
C.3.3 Condition Monitoring Limit
C-34
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
Table C-3Relational and Material Uncertainties Calculated at the 95 th Percentile
C.3.4 Growth
C-35
Appendix C: Examples of Condition Monitoring and Operational Assessment Limit Determination
Table C-4Postulated Distribution of Growth of Uniform Thinning Indications for Operational Assessment Calculations (OD = 0.875, t =0.050)
C-36
rx ~ 17 E~rzz r7- tzz- r-c rizi r-_ r~ L tI [ r, r , r
V-7 Sf7 F- 7 r~ r7 V-- SF- C=7 U7 1-7 r7 U>_!?r r-, Ur- C r -u rz
Appendix C: Examples of Condition Monitoring and Operational Assessment Limit Determination
Figure C-3Distribution of Growth for Uniform Thinning
C-37
Appendix C.: Examples of Condition Monitoring and Operational Assessment LimfitDetermination
C.3.5 Monte Carlo Analysis
Lj
LiUL
UUL
C-38 L
L
V1777 r-7 r7 -- U7-- E77] 9771 r7l 1717 FiT U r - r- - r-- U r-
Appendix C: Examples of Condition Monitoring and Operational Assessment Limit Determination
Figure C-4Comparison of CM solutions for a burst pressure of 4.473 ksi
C-39
Appendix C: Examples of Condition Monitoring and Operational Assessment Limit Determnination
Figure C-5Distribution of simulated burst pressures for a sample depth and length
C-40
r7 r- > rr rz 7 rz rn z z rz 'v ix r7ci r( - r --- F
Appendix C: Examples of Condition Monitoring and Operational Assessment LimitDetermination
CA References
C1 Steam Generator Degradation Specific Management Flaw Handbook, EPRI, Palo Alto, CA:January 2001. 1001191
C2 Burst Pressure Correlation for Steam Generator Tubes With Throughwall Axial Cracks,EPRI, Palo Alto, CA: 1997. TR-105505
C3 Impacts of the Structural Integrity Performance Criterion on Steam Generator Tube IntegrityEvaluations, EPRI, Palo Alto, CA: 2004. 1009541
C4 McKay, M. D., R. J. Beckman, and W. J. Conover, "A Comparison of Three Methods forSelecting Values of Input Variables in the Analysis of Output from a Computer Code,"Technometrics, Vol. 21, No. 2, May 1979.
C5 Pressurized Water Reactor Steam Generator Examination Guidelines: Revision 6, EPRI, PaloAlto, CA: September 1997. 1003138.
C-41