ML22013A303

Trp 143.2 St Lucie SLRA - Breakout Questions Non-Class 1 Fatigue

ML22013A303
Person / Time
Site:	Saint Lucie
Issue date:	12/21/2021
From:	Office of Nuclear Reactor Regulation
To:
Rodriguez-Luccioni H
References
EPID L-2021-SLR-0002, L-2021-SLR-0002
Download: ML22013A303 (2)

Text

Plant Name SLRA: Breakout Questions SLRA Section 4.3.2, Metal Fatigue of Non-Class 1 Components TRP: 143.2 Note: Breakout Questions are provided to the applicant and will be incorporated into the publicly-available audit report.

Technical Reviewer Seung Min 11/29/2021 Technical Branch Chief Matt Mitchell 12/21/2021 Breakout Session Date/Time To be filled in by PM Applicant Staff NRC staff To be filled out by PM during breakout Question SLRA SLRA Background / Issue Discussion Question / Request Outcome of Discussion Number Section Page (As applicable/needed) 1 4.3.2 4.3-18 SLRA Table 4.3.3-2 indicates that the 1. Clarify whether the thermal (Table reactor coolant sampling line is subject to expansion stress (SE) of 4.3.2-2) approximately 29200 cycles for 80 years the sampling lines meets of operation. Therefore, the relevant the acceptance criterion stress range reduction factor for the (i.e., the stress does not sampling lines is 0.7, which allows exceed the allowable thermal cycles up to 45,000. stress range (SA), as modified by applying the However, the SLRA does not clearly stress reduction for the discuss how the stress analysis for piping). As part of the sampling lines with the stress reduction clarification, provide the SE factor (0.7) meets a relevant acceptance and SA values.

criterion.

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Question SLRA SLRA Background / Issue Discussion Question / Request Outcome of Discussion Number Section Page (As applicable/needed) 2 4.3.2 4.3-16 SLRA Section 4.3.2 indicates that the 1. Clarify whether the non-Class 1 mechanical systems or approach for determining portions of systems with operating susceptibility to thermal temperatures above 220 °F are fatigue for 80 years of conservatively evaluated for metal operation is consistent with fatigue. This approach is based on the that used in the current applicants determination that the non- licensing basis non-Class 1 Class 1 piping at an operating fatigue analysis. If not, temperature below 220 °F is not explain why a different susceptible to thermal fatigue. approach is used.

The staff needs to clarify whether the approach for determining susceptibility to thermal fatigue for 80 years of operation is consistent with that used in the current licensing basis non-Class 1 fatigue analysis.

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