ML22139A137
| ML22139A137 | |
| Person / Time | |
|---|---|
| Issue date: | 05/20/2022 |
| From: | Bill Lin NRC/RES/DE |
| To: | |
| Roche-Rivera, R | |
| Shared Package | |
| ML22061A243 | List: |
| References | |
| RG-1.246, Rev 0 | |
| Download: ML22139A137 (27) | |
Text
Overview of ASME Section XI, Division 2, Reliability and Integrity Management (RIM) Programs for Nuclear Power Plants May 20, 2022 Bruce Lin, Materials Engineer Reactor Engineering Branch Division of Engineering Office of Nuclear Regulatory Research
- ASME Section XI, Division 1 was developed and evolved over 40+ years but focused on existing PWR and BWR light water reactor (LWR) technology
- Consequently, the use of ASME Section XI, Division 1 may not be well suited for advanced Non-LWR reactor designs
- ASME Section XI, Division 2 Reliability and Integrity Management (RIM) was developed to be a technology neutral inservice code that can be applied to all reactor types
- RIM has technology-specific supplements intended to account for different reactor designs
- Many of the technology-specific supplements are still under development 2
What is RIM?
- A program to ensure that passive component reliability and integrity are properly managed
- Based on achieving an acceptable level of reliability
- Implement strategies to ensure that Reliability Targets for SSCs are defined, achieved, and maintained throughout the plant lifetime 3
RIM Process Philosophy
- RIM evaluates all SSCs for their impact to plant safety and reliability
- RIM establishes the examination, tests, operation, monitoring, and maintenance requirements to ensure the SSCs meet the plant risk and reliability goals
- This contrasts the prescriptive approach used by Division 1 which uses Class 1, Class 2 and Class 3 approach to ISI with each Class having less rigorous criteria 4
RIM Process Overview
- Step 1: Determine Scope of SSCs for RIM Program
- Step 2: Evaluate SSC Damage Mechanisms
- Step 3: Determine Plant and SSC Level Reliability and Capability Requirements
- Step 4: Identify and Evaluate RIM Strategies to Achieve Reliability Targets
- Step 5: Evaluate Uncertainties in Reliability Performance
- Step 6: Implement RIM Program
- Step 7: Monitor SSC Reliability Performance and Update RIM Program 5
Step 1: RIM Scope
- Applicable over the entire life of the plant and each passive SSC that is in scope [RIM-1.1]
- The Owner shall document the specific list of SSCs to be evaluated for inclusion within the scope of the RIM Program [RIM-2.2]
- The scope shall include SSCs whose failure could adversely affect plant safety and reliability [RIM-2.2]
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Step 2: Degradation Mechanisms Assessment
- The potential active degradation mechanisms for the SSCs within the RIM Program scope shall be identified and evaluated [RIM 2.3]
- Design characteristics
- Operating experience and research experience
- Results of preservice and in-service examinations
- Recommendations by SSC vendors
- Applicable degradation mechanisms including those identified in the applicable Plant Type Mandatory Appendix
- The criteria used to identify and evaluate the susceptibility of each SSC to degradation mechanisms shall be specified in the RIM program documentation 7
Step 3: Plant and SSC Reliability
- Plant Level Risk and Reliability Targets [RIM-2.4.1]
- Plant level reliability shall be derived from regulatory limits on the risks, frequencies, and radiological consequences of licensing basis events that are defined in the probabilistic risk assessment (PRA)
- Plant level RIM goals may include additional goals to meet plant availability
- SSC Level Reliability Target [RIM-2.4.2]
- Allocation of SSC level Reliability Targets from PRA
- Mandatory Appendix II provides a general approach
- Scope, Level of Details, and Technical Adequacy of PRA [RIM-2.4.3]
- PRA shall meet the requirements of the ASME/ANS RA-S-1.4 8
Step 4: RIM Strategies
- The RIM Expert Panel (RIMEP) shall identify the RIM strategies and evaluate and select combinations of strategies that will meet and maintain the Reliability Targets [RIM-2.5]
- RIM strategies may include design strategies, operating practices, inservice inspection, repair and replacement practices, etc.
- The RIM strategies shall account for the potential for specific damage mechanisms applicable to each SSC
- Impact of each RIM strategy on the reliability of each SSC shall be assessed against the SSC-level Reliability Targets 9
Step 5: Evaluate Uncertainties
- Evaluation of Uncertainties [RIM-2.6]
- Lack of service experience
- Unknown degradation mechanisms
- Uncertainties in the prediction of SSC reliability
- Use of multiple strategies to address uncertainties 10
Step 6: RIM Implementation
- RIM Program Documentation
- Scope of SCCs selected for inclusion in RIM program
- Results of degradation mechanisms assessment
- Plant level risk and reliability goals and SCC reliability targets
- Specific RIM strategies and their impact on SCC reliability performance
- Evaluation of uncertainties
- RIM Program Implementation [RIM-2.7]
- Inspection Interval
- Preservice Inspections
- Design Requirements for RIM
- Leak Detection System Requirements for RIM
- Examination and Inspection Requirements for RIM 11
Step 7: RIM Program Updates
- Performance Monitoring and RIM Program Updates [RIM-2.8]
- RIM program shall be re-evaluated to incorporate results from SSC performance monitoring and new information affecting implementation of the program
- Examples may include changes to plant design, operating and maintenance practices, plant, industry and research experience, monitoring or examination results, regulatory requirements, PRA updates, etc.
- Minimum frequency of updates - Once per inspection interval 12
Expert Panels
- RIM Expert Panel (RIMEP)
- RIMEP is responsible for the technical oversight and direction of the risk-informed aspects of RIM program development and implementation.
- Establishes RIM Scope
- Establishes Reliability Targets
- Identifies RIM Strategies
- Monitoring and NDE Expert Panel (MANDEEP)
- Responsible for all things NDE
- Develops MANDE specifications
- MANDE qualification
- Specific examination requirements
- Minimum criteria of MANDE 13
Section XI, Division 2 Organization
- RIM-1 Scope and Responsibility - Similar to Div. 1 IWA-1000
- RIM-2 Reliability and Integrity Management (RIM) Program - This article covers RIM program implementation
- RIM-3 Acceptance Standards - Appendix VII will have acceptance standards for each reactor type
- RIM-4 Repair/Replacements Activities - Done in accordance with Div. 1 IWA 4000 with a few exceptions
- RIM-5 System Leak Monitoring and Periodic Tests - Provides rules for leakage monitoring and leak testing
- RIM-6 Records and Reports - Similar to Div. 1 IWA-6000
- RIM-7 Glossary 14
Section XI, Division 2 Organization Mandatory Appendices
- Appendix I, RIM Decision Flowcharts
- Appendix II, Derivation of Component Reliability Targets From Plant Safety Requirements
- Appendix III, Owners Record and Report for RIM Program Activities
- Appendix IV, Monitoring and NDE Qualification
- Appendix V, Catalog of NDE Requirements and Areas of Interest
- Appendix VI, Reliability and Integrity Management Expert Panel
- Appendix VII, Supplements for Types of Nuclear Plants Nonmandatory Appendices
- Appendix A, Alternate Requirements for NDE and Monitoring
- Appendix B, Regulatory Administrative Provisions for Nuclear Plants Using RIM Program 15
Overview of RG 1.246 Endorsement of ASME Section XI, Division 2, and Resolution of DG-1383 Public Comments May 20, 2022 Steve Philpott, Project Manager / Acting Branch Chief Advanced Reactor Technical Branch 2 Division of Advanced Reactors and Non-Power Production and Utilization Facilities Office of Nuclear Reactor Regulation
Background
- ASME issued Section XI, Division 2 Requirements for Reliability and Integrity Management (RIM) Programs for Nuclear Power Plants in the 2019 Edition of the BPV Code.
- ASME requested NRC endorsement in October 2019.
- NRC responded to ASME in August 2020 and formed a review working group.
- Staff working group reviewed Section XI, Division 2 for endorsement via regulatory guide for applicability to non-light water reactors (Non-LWRs).
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RIM Review Summary
- Reviewed code and developed initial staff positions:
Aug - Dec 2020 o confirmed RIM is appropriate to endorse with conditions
- Developed staff positions and draft regulatory guide (DG-1383): Jan - Sep 2021
- Published DG-1383 in Sep 2021: 45-day public comment period
- Comment resolution and concurrence review:
Nov 2021 - Apr 2022
- Publish Final RG: Jun 2022 18
RG 1.246 Structure
- Section A o Purpose o Applicability (Non-LWRs) o Applicable Regulations and Related Guidance
- Section B o Background o Bases for NRC Staff Positions
- Section C o Staff Regulatory Guidance (Conditions) 19
RG 1.246 Conditions Condition 1: Applicants intending to use RIM should include a license condition / Identifies information to be included in their application Condition 4: Changes to a RIM program and information to be provided to the NRC for review and approval / for information Condition 10: RIM provisions in the course of preparation or otherwise under development 20
RG 1.246 Conditions Additional conditions:
- Use with 2019 Edition of Section XI-Division 1
- Document how aspects of Section XI-Division 2 are considered
- ANDE-1 not approved for personnel Qualification
- Editions of supporting standards acceptable for use
- Justify acceptability of the PRA in RIM program
- Cannot override construction code NDE without approval 21
RG 1.246 Conditions Additional conditions:
- Preservice inspections for repair and replacement
- Appendix V to be considered for low pressure applications
- Stress relaxation to be considered as a degradation mechanism
- Liquid leak test clarifications and hold time limits
- Minor errata type corrections 22
DG-1383 Public Comments
- Received 8 distinct comment submissions
- Approximately 35 individual comments
- No additional or eliminated conditions
- Clarified applicability, information to be submitted for review, and other staff positions 23
DG-1383 Public Comments
- Change in Applicability: Multiple comments suggested that RG 1.246 should include applicability to LWR designs. For some LWR cooled /
moderated advanced reactors, it would be difficult to implement Section XI, Division 1. RIM is intended to be technology neutral.
- One commenter recommended rulemaking to amend 50.55(a).
- Rulemaking is outside the scope of this RG
- Staff reviewed and is endorsing ASME BPV Code,Section XI, Division 2 only for use by non-LWRs.
- 10 CFR 50.55a(g) mandates the use of the ASME BPV Code,Section XI, Division 1 for boiling and pressurized water-cooled reactors.
- Staff agrees that RIM was developed for any type of reactor design.
- Added footnote in Background section in the RG:
RIM was developed for any type of reactor design. However, 10 CFR 50.55a(g) mandates the use of the ASME Code,Section XI, Division 1 for boiling and pressurized reactors. If a boiling or pressurized water-cooled reactor licensee or applicant wishes to use RIM, they would need to request an exemption under 10 CFR 50.12 or 10 CFR 52.7 from 10 CFR 50.55a(g).
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DG-1383 Public Comments Clarifications of Regulatory Guidance Positions
- Position 1 o Listing of SSCs included in the scope of the RIM program rather than a summary of the bases for the scope o Description of the types of factors from RIM-2.5.1 used in the RIM strategies o Clarified justification for flaw evaluation acceptance criteria temperature limits to be consistent with the temperature limits of the applicants construction code
- Positions 1 and 4 o Removed the need to submit the NIS-2 form and removed references to the NIS-2 o The term refueling outage was removed and changed to use the term scheduled outage to be consistent with Appendix B of ASME Code,Section XI, Division 2 25
DG-1383 Public Comments Clarifications of Regulatory Guidance Positions
- Position 5 o For use of ANSI/ASNTCP189 - added including any conditions applied under 10 CFR 50.55a(b)(2) o Added clarification for performance demonstration of NDE methods and techniques o Performance demonstration is beyond the scope of ANSI/ASNT CP189 and ANDE-1 o Use Section XI, Division 1 Appendix VIII
- Additional clarification changes 26
Acronyms/Abbreviations ANDE ASME Non-destructive Examination ANS American Nuclear Society ASME American Society of Mechanical Engineers ANSI/ASNT American National Standards Institute / American Society for Nondestructive Testing BPV Boiler and Pressure Vessel BWR Boiling Water Reactor CFR Code of Federal Regulations DG Draft Guide / Draft Regulatory Guide ISI Inservice Inspection LWR Light Water Reactor NDE Non-destructive Examination Non-LWR Non-Light Water Reactor MANDE Monitoring and NDE MANDEEP Monitoring and NDE Expert Panel PRA Probabilistic Risk Assessment PWR Pressurized Water Reactor RIM Reliability and Integrity Management RIMEP RIM Expert Panel SSCs Structures, Systems, and Components 27