ML23038A005
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| ML23038A005 | |
| Person / Time | |
|---|---|
| Issue date: | 03/31/2022 |
| From: | Margaret Audrain NRC/NRR/DANU/UARP |
| To: | |
| References | |
| Download: ML23038A005 (1) | |
Text
Pre-Application Engagement on Materials Qualification Issues for Advanced Reactor Licensing Meg Audrain Office of Nuclear Reactor Regulation March 2023 Advanced Reactor Stakeholder Meeting
Agenda
- Why have pre-application engagements?
- Code Requirements
- Environmental Testing
- Design Envelope
- Non-Code Qualified Materials 2
Why have early engagement?
- Encouraged for all materials used in safety related and risk-significant applications
- Important to ensure NRC staff and applicants have a common understanding on data requirements for these materials
- More efficient for applicants and NRC staff to do this in pre-application space to ensure timely application reviews.
- Significant lead time for materials testing could lead to delays if not addressed early 3
ASME Code Requirements
- NRC staff anticipates most applicants will qualify materials and designs to ASME Section III, Division 5, because many of the proposed designs operate at temperatures or in environments where existing Codes endorsed by the NRC or incorporated by reference do not apply.
- Applicants should demonstrate how their design complies with Div 5, as conditioned in RG 1.87
- Applicants should justify deviations from Div 5 and demonstrate why the proposed deviations are acceptable. The use of alternative codes of construction should include a delta analysis.
4
Environmental Testing
- Div 5 rules do not cover deterioration that may occur in service as a result of radiation effects, corrosion, erosion, thermal embrittlement, or instability of the material but states that these effects shall be taken into account for design or service life
- Applicant should provide this information as further described in the NRCs forthcoming Materials in Advanced Reactors ISG
- Data is potentially time consuming to gather and results could impact design or component lifetimes 5
Environmental Testing
- Used to develop corrosion or degradation rates for specific reactor environments
- Needed to understand environmental effects and their impacts on mechanical and thermal behavior
- Needed to set appropriate limits on coolant purity
- Not explicitly addressed like it is for LWRs
- No coolant purity standards exist for non-LWR environments
- Needed to determine if transient could potentially be end of life event 6
Data Supports Design Envelope
- Should show that any data used, historic or planned, is directly applicable to plant design and environment
- Data should support design for operating and accident conditions
- Confirm that any standards referenced in Div 5 were used or provide a delta analysis for standards that were used (e.g., QA programs) 7
Use of non-Code Qualified Materials
- For use of non-Code Qualified materials, the NRC will review material qualification data
- ensure material and mechanical properties support intended functions
- environmental testing still needed
- Applicants should demonstrate that graphite will be qualified as per Div 5. In addition, any deviations from Code should be addressed 8
Conclusions
- Early engagement is important to support timely application reviews
- NRC wants to ensure a common understanding on data qualification and any potential testing requirements during pre-application
- Beneficial to both NRC staff and applicants 9
Questions?