Document: NRC Regulatory Guide
Document ID: 08cebcdf-2e81-4e08-a508-9f6b4701c0a5
Document Type: regulatory_guide
Title: Design, Fabrication, and Materials Code Case Acceptability, ASME Section III (Rev. 40)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2219/ML22195A282.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.84
CFR Part: 
CFR Title: 

Content:
ence frequent sustained loads in service. The last sentence of Paragraph 5.3 of the Code Case should reference Paragraph 4.5.2.2 of the AWS D.1.1 Code for the evidence presented to and accepted by the authorized inspector concerning exposure of electrodes for longer periods of time. Paragraph 16.2.2 is not acceptable as written and should be replaced with the following: “When not exempted by 16.2.1, above, the postweld heat treatment shall be performed in accordance with NF-4622 except that for ASTM A-710 Grade A material, it should be at least 1000°F (540°C) and should not exceed 1150°F (620°C) for Class 1 and Class 2 material and 1175°F (640°C) for Class 3 material. The new holding time at temperature for weld thickness (nominal) should be 30 minutes for 2 inches or less, 1 hour per inch for thickness over 2 inches to 5 inches, and 5 hours plus 15 minutes for each additional inch over 5 inches.” 2/20/84 N-71-13 N-71-14 N-71-15 N-71-16 N-71-17 N-71-18 Additional Materials for Subsection NF, Classes 1, 2, 3 and MC Component Supports Fabricated by Welding, Section III, Division 1 (1) The maximum measured UTS of the component support material must not exceed 170 ksi because of the susceptibility of high-strength materials to brittleness and stress-corrosion cracking. (2) Certain applications may exist for which a UTS value of up to 190 ksi could be considered acceptable for a material; under this condition, the design specification must specify impact testing for the material. For these cases, the applicant must demonstrate that (1) the impact test results for the material meet the Code requirements and (2) the material is not subject to stress-corrosion cracking because a corrosive environment is not present and because the component that contains the material has essentially no residual stresses or assembly stresses and it does not experience frequent sustained loads in service. (3) In the last sentence of Paragraph 5.3 of the Code Case, reference must be