ML24172A295
| ML24172A295 | |
| Person / Time | |
|---|---|
| Issue date: | 06/25/2024 |
| From: | Robert Tregoning NRC/RES/DE |
| To: | |
| Rezai, A., NRR/DNRL, 301-415-1328 | |
| Shared Package | |
| ML24159A553 | List: |
| References | |
| Download: ML24172A295 (18) | |
Text
Overview of NRC Materials Research Supporting Long-Term Operation Rob Tregoning Nuclear Regulatory Commission Industry/NRC Materials Technical Exchange Meeting June 25-27, 2024 Materials and Aging Research
- Research objectives
- Improve timeliness of regulatory decision-making on the use of new materials, manufacturing technologies, and inservice inspection techniques through independent and confirmatory research
- Address materials degradation during long-term plant operation
- Inform and enhance the use of risk information in regulatory decision making
- Strategic Focus Areas
- Support resolution of safety-significant technical issues
- Maintain core capabilities to support emerging technical needs related to corrosion, metallurgy, component integrity assessment, and non-destructive examination
- Enhance modeling/analytical tools to support efficient regulatory decision-making
- Foster collaborations with domestic and international counterparts to stimulate information sharing and cooperative research approaches
- More information contained in U.S.NRCs Research Prospectus for Fiscal Years 2022 - 2024 (ML22235A651)
2 Long-Term Operation (LTO) & Aging Management
- What are w e doing? Supporting guidance development, coordinating related research activities, developing a systematic approach for harvesting materials and components from reactors.
- Motivation: Provide assurance that aging effects will be adequately managed during LTO.
- Regulatory Application: Refine, as appropriate, existing aging management programs and guidance
- Significant activities
- Draft report on knowledge gaps in online monitoring and structural health management for NPP LTO in FY24
- Collaborating with EPRI on cables aging management workshop (June 13-14, 2024)
- Workshops on structural materials (metals and concrete) researchfor LTO (October 1-4, 2024)
3 Materials Harvesting
- What are w e doing? Extracting materials from decommissioning or operating plants for laboratory testing
- Objective: Improve understanding of material degradation associated with LTO
- Motivation: Confirm information on aging mechanisms generated through other research programs and operating experience
- Regulatory Application: Inform aging management approaches for LTO
- Significant activities
- OECD/NEA SMILE project (2021-2025), potential SMILE 2 project (2026- )
- Obtained Ringhals A690 CRDM nozzles and SGT piece 4 - Updating NRCs harvesting priorities Irradiation Assisted Degradation (IAD)
- What are w e doing? Testing highly irradiated materials to characterize irradiation effects on materials performance
- Motivation: Confirm adequacy of reactor internals aging management programs
- Regulatory Application: Support reviews of internals inspection/ evaluation guidance, ASME Code changes and associated rulemaking
- Significant activities
- Testing Zorita RVI materials
- Participating in OECD/NEA SMILE project
- Participating in FIDES project
5 Primary Water Stress Corrosion Cracking (PWSCC)
- What are w e doing? Evaluating Alloy 690/52/152 crack growth rate (CGR), crack initiation, and long-term aging performance
- Motivation: Provide assurance of reactor coolant pressure boundary integrity
- Regulatory Application: Support reviews of proposed changes to the inspection requirements in the ASME Code and associated rulemaking
- Significant activities
- Evaluating temperature and dissolved hydrogen effects on CGR
- Investigating HAZ, dilution zone, and pre-existing defects effects on crack initiation
- Participating in expert panel CGR evaluations
6 Steam Generator Tube Integrity Program (SG-TIP)
- Regulatory Application: Review acceptability of current and new approaches to inspection techniques and changes to SG guidelines as proposed by industry
- Significant activities
- Report evaluating eddy current sizing capabilities for PWSCC at expansion transition regions of SG tubing
- Independent assessments of industry ET approach and probe-probe equivalency.
7 Probabilistic Integrity Assessment
- What are w e doing? Developing probabilistic methods to assess structural integrity of RPV and piping components
- Motivation: Confirm continued integrity of safety-critical components subject to degradation
- Regulatory Application: Support review of related Code and industry applications and evaluate emergent operating experience
- Significant activities
- Issue FAVPRO v1.0.x PFM code for RPV integrity and associated manuals and QA documentation
- Continue development and modernization of the xLPR code (i.e., V2.4) for probabilistic piping integrity
- Confirming LOCA frequency estimates from NUREG-1829
8 Piping Integrity
- What are w e doing? Developing and enhancing analytical methods and tools for assessing structural integrity of reactor piping systems; specific topics on
- Leak-before-break (LBB)
- High energy line break (HELB)
- Thermal embrittlement (TE) of cast austenitic stainless steel (CASS) and austenitic stainless-steel welds (ASSW)
- Motivation: Confirm integrity of safety-critical piping systems during LTO
- Regulatory Application: Enhance guidance for piping structural integrity calculations
- Significant Activities
- Supporting review of industrys risk-informed HELB method
- Considering developing alternative HELB framework for existing and new reactors
- Updating Flaw Evaluation Software (FES) for evaluating PWSCC in piping and CRDM nozzles 9 - Completing reports on TE of CASS and ASSW Nondestructive Evaluation (NDE)
- What are w e doing? Evaluating effectiveness and reliability of NDE techniques
- Motivation: Confirm adequacy of industry procedures and practices
- Regulatory Application: Support reviews of ASME Code modifications and proposed revisions of current requirements
- Collaboration: EPRI, IRSN, and PIONIC
- Significant activities
- Completed report on assessment of ML applied to UT NDE
- Evaluating effectiveness of virtual and synthetic flaws for training and qualification testing
- Assessing NDE capabilities for carbon fiber reinforced composite repairs
- Assessing capabilities of ML and automated data analysis in NDE
10 Concrete Research
- What are w e doing? Evaluating concrete aging and performance for LTO
- Motivation: Understand significance of aging mechanisms identified through research and operating experience
- Regulatory Application: Confirm adequacy and reduce uncertainties associated with aging management programs
- Significant activities
- Evaluating effects of irradiation on concrete biological shield structures and concrete-rebar bond
- Exploring harvesting of irradiated concrete materials
- Completing study on creep and shrinkage effects on prestressed concrete containment vessels (PCCVs)
11 Cables Research
- What are w e doing? Evaluating cable aging effects on environmental qualification (EQ) and condition monitoring (CM) for LTO NUREG 7300NUREG 7300NUREG 7300
Published 2023Published 2023Published 2023
Cable Condition Monitoring Study:Cable Condition Monitoring Study:Cable Condition Monitoring Study:
- Condition monitoring while Condition monitoring while Condition monitoring while
- Motivation: Ensure acceptable cable performance and reduce aging samplesaging samplesaging samples
- Performed LOCA testingPerformed LOCA testingPerformed LOCA testing uncertainties associated with aging management programs
- Regulatory Application: Confirm adequacy of Tan Delta TestingTan Delta TestingTan Delta TestingConditionConditionConditionEMDA UncertaintiesEMDA UncertaintiesEMDA Uncertainties
Re se ar ch I nfor ma ti on L et ter R ESRe se ar ch I nfor ma ti on L et ter R ESRe se ar ch I nfor ma ti on L et ter R ES---202120212021---011011011MonitoringMonitoringMonitoring industry-proposed CM techniques to effectively identify
- Statistical Analysis of EPRI Tan Statistical Analysis of EPRI Tan Statistical Analysis of EPRI Tan *** Review researc h effortsReview researc h effortsReview researc h efforts Delta GuidesDelta GuidesDelta GuidesSubmergedSubmergedSubmergedNRCNRCNRCMaterialMaterialMaterial*** Summarize findings and Summarize findings and Summarize findings and adverse cable performance *** Evaluated confidenc e level in Evaluated confidenc e level in Evaluated confidenc e level in Cab lesCab lesCab lesR ese a rc h R ese a rc h R ese a rc h ScienceScienceSciencea ttri b ute sa ttri b ute sa ttri b ute s EPRI recommended guidelines EPRI recommended guidelines EPRI recommended guidelines *** Evaluate conclusions and resultsEvaluate conclusions and resultsEvaluate conclusions and results for test results evaluationfor test results evaluationfor test results evaluation
Fu tureFu tureFu ture
- Significant activities Mot ivat ionMot ivat ionMot ivat ion Innovati ve Condition Innovati ve Condition Innovati ve Condition NRC Commission directionNRC Commission directionNRC Commission directionMonitoringMonitoringMonitoring
Pe rform ance during L TO:Pe rform ance during L TO:Pe rform ance during L TO:
- Studied relationship between cable performance and condition *** Degradation and aging effects Degradation and aging effects Degradation and aging effects *** Identify innovative methodsIdentify innovative methodsIdentify innovative methods understandingunderstandingunderstanding *** Evaluate merits and trendsEvaluate merits and trendsEvaluate merits and trends
- Condition monitoringCondition monitoringCondition monitoring*** Identify methods applicable to Identify methods applicable to Identify methods applicable to monitoring attributes *** EQ extension and service lifeEQ extension and service lifeEQ extension and service lifeCBQ per RG 1.89 Rev. 2CBQ per RG 1.89 Rev. 2CBQ per RG 1.89 Rev. 2
- Aging m anageme nt Aging m anageme nt Aging m anageme nt
- Evaluated efficacy of Tan-Delta testing
- Exploring innovative CM techniques and their ability to support condition-based qualification (CBQ)
12 Summary
- NRC Office of Nuclear Regulatory Research conducts confirmatory research to establish technical bases that support regulatory decisions and development of regulatory guidance documents
- NRC staff exchanges information with domestic and international counterparts on materials performance and aging management of nuclear power plant structures and components and conducts independent analyses
- Research results
- Operating experience
- Research activities are prioritized to address potential safety -significant technical issues.
- Long-lead-time confirmatory research is an important consideration in proactive aging management.
- For more information contact: Robert.Tregoning@nrc.gov
14 Select Recently Published Reports
2nd Workshop on International Harvesting Cooperation: Summary Report, November 2022 (ML23347A144)
NRC Technical Assessment of Zorita Materials Testing Results, RIL 2022- 05, May 2022 (ML22132A039)
Chemical Compositional Analysis and Microstructural Characterization of Harvested Zorita Reactor Pressure Vessel (RPV) Internals, INL/EXT 62220, March 2021 (ML22249A319)
Cracking Behavior of Irradiated Ex-Plant Materials, ANL-22/22, June 2022 (ML21124A112)
Primary Water Stress Corrosion Cracking of High-Chromium Nickel-Base Welds at or Near Interfaces - 2020, NUREG/CR-7277, April 2023 (ML23095A385)
CSNI Leak-Before-Break Benchmark - Summary of Phase I, SMiRT 26, July 2022 (ML22161A476).
Technical Support for Component Integrity - Postulated Pipe Rupture Locations, TLR-RES/DE/REB-2022- 09, October 2022 (ML22277A504)
15 15 Select Recently Published Reports
Evaluation of Factors Affecting Durability of Carbon Fiber Reinforced Polymer Composite Repairs
- Single-Ply Laminate Study, TLR-RES/DE/REB-2022- 02, April 2022 (ML22118A351)
Risk-informed Assessment of French Stress Corrosion Cracking Operational Experience Relative to US Fleet (ML23236A080)
Development and testing of coarse-grained models for ultrasonic simulations of cast austenitic stainless steel, Ultrasonics, September 2023 (ML23318A217)
Evaluating Flaw Detectability Under Limited-Coverage Conditions, NUREG/CR-7304, October 2023 (ML23284A269)
An Assessment of Machine Learning Applied to Ultrasonic Nondestructive Evaluation, ORNL/SPR-2023/3245, February 2024 (ML24046A150)
Classification of Ultrasonic B-Scan Images from Welding Defects Using A Convolutional Neural Network, NPIC&HMIT 2023, July 2023 (ML23241A961)
16 16 Select Recently Published Reports
NUREG/CR-7280, Review of Radiation Induced Concrete Degradation and Potential Implications for Structures Exposed to High, Long-Term Radiation Levels in Nuclear Power Plants, July 2021 ( ML21202A265)
RIL 2021- 07, Radiation Effects on Concrete - An Approach for Modeling Degradation of Concrete Properties, August 2021 ( ML21238A064)
NUREG/CR-7281, Radiation Evaluation Methodology for Concrete Structures, July 2021 (ML21216A100)
RIL 2022- 06, Aging of PCCV with Emphasis on Creep and Creep Rupture, March 2022 (ML22075A007)
RIL 2022- 07, Assessment of the San Onofre Concrete Susceptibility against Radiation Damage, 2022 ( ML22119A092)
17 17 Select Recently Published Reports
Assessing In-Situ Mechanical Properties of ASR-Affected Concrete, NIST Technical Note 2121, February 2021 Assessing Bond and Anchorage of Reinforcing Bars in ASR -Affected Concrete, NIST Technical Note 2127, February 2021 Assessing Cyclic Performance of ASR-Affected Concrete Shear Walls, NIST Technical Note 2180, September 2021 Material Research Support for the Structural Performance of Nuclear Power Plant Concrete Structures Affected by Alkali-Silica Reaction, NISTIR 8415, May 2022
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