Document: NRC Regulatory Guide
Document ID: 2704425a-c58a-45c4-93ab-8761721c3e7a
Document Type: regulatory_guide
Title: Evaluation of Reactor Pressure Vessels with Charpy Upper-Shelf Energy Less Than 50 Ft-Lb
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740038.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.161
CFR Part: 
CFR Title: 

Content:
lear utilities, nuclear power plant vendors, consultants, and S academia. Similarly, the evaluation procedures for Service Levels A and B were developed by this group. The procedures in the regulatory guide for Service Levels A and B are essentially identical to those in Appendix K to ASME Section 3. Thus, the aoceptance criteria and die evaluation procedures for thc service levels that generally control the analyses are based on the consensus technical 6pinion of a large group of technical cxpes and were developed over an extended period. The evaluation procedures for Service Levels C and D were developed by the staff and build on the procedures for Service Levels A and B. As part of a continuing effort by die ASME Section XI working group, the NRC staff has compared 1he regulatory guide procedures to odr procedures that are being developed by various organizaticns. The comparison was very favorbl; with the procedures proposed in the regulatory guide predicting lower acceptable Charpy upper-shelf energy values than would be predicted by the other procedures, which were less rigorous and, consequently, more conservative. The procedures for transient selection are based on procedures that have already been endorsed by the star Alternatively, generic bounding transients can be used ifjustified. The guidance on material properties is based on a state-of-the-art statistical evaluation of all available fracture touglmess data. A broad range of alternatives is offered in the regulatory guide so that methods acceptable to the staff arc offered for virtually every siuation and combination of circumstances. The regulatory guidc provides timely, cost-effectivc guidance that is based on the consensus of a lar group of tecdincal experts represnting divers• badcgmrmds and nerecst The specific guidance is comprehensive and would provide an effective and definitive approach to performing equivalent margin anaiyscs. 'N L PR ein g r J n meycled~ Federal Recycling Program R-3 }