Document: NRC Regulatory Guide
Document ID: 1fd6c427-a283-44d1-b442-31901b507b4a
Document Type: regulatory_guide
Title: Acceptability of ASME Code Section III, Division 5, 'High Temperature Reactors' (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2202/ML22026A517.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.87
CFR Part: 
CFR Title: 

Content:
-872, which the staff proposes to endorse without conditions; (2) renumber what was previously designated as Table 1 in DG-1380 to Table 2, “Conditionally Acceptable ASME Code, Section III, Division 5 Code Cases”; and (3) add Code Case N-898 with proposed conditions in the renumbered Table 2 as follows: Table 1. Acceptable ASME Code, Section III, Division 5 Code Cases Code Case Number Code Case Title Supplement/Edition N-872 Use of 52Ni-22Cr-13Co-9Mo Alloy 617 (UNS N06617) for Low Temperature Service Construction, Section III, Division 5.” 0/2017 6 Table 2. Conditionally Acceptable ASME Code, Section III, Division 5 Code Cases Code Case Number Code Case Title/Limitation Supplement/Edition … … … N-898 Use of Alloy 617 (UNS N06617) for Class A Elevated Temperature Service Construction Section III, Division 5 4/2019 When applying HBB-T-1710 and HBB-4800 to Alloy 617 components, applicants and licensees should develop their own plans to address the potential for stress relaxation cracking in their designs. These plans should address factors such as weld joint design and controls on welding in addition to the required heat treatment of HBB-4800. When applying HBB-T-1836(2)(-b), the equation for plastic strain in the code case should be replaced with the following equation: for a > a1 , E = − 1 1− a− a1 8 ap − a1 IV. Backfitting, Forward Fitting, and Issue Finality DG-1380, if finalized, would not constitute backfitting as defined in section 50.109 of title 10 of the Code of Federal Regulations (10 CFR), “Backfitting,” and as described in NRC Management Directive (MD) 8.4, “Management of Backfitting, Forward Fitting, Issue Finality, and Information Requests” (ADAMS Accession No. ML18093B087); constitute forward fitting as that term is defined and described in MD 8.4; or affect the issue finality of any approval issued under 10 CFR part 52, “Licenses, Certificates, and Approvals for Nuclear Power Plants.” The guidance would not apply to any