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:
s to which the Code Case is applied for review on a case-by-case basis. 2/20/87 N-404 Annealed Alloy UNS N06625 Over UNS N06600 Bimetallic Tubing, Section III, Division 1, Class 1 The outside layer of the bimetallic tubing should be limited to a minimum of 5 percent and to a maximum of 40 percent of the wall thickness. The tolerance on the outside layer of material should not exceed -0.000 to +0.007 inch of the specified design wall thickness. 12/11/95 N-411-1 Alternative Damping Values for Response Spectra Analysis of Class 1, 2, and 3 Piping, Section III, Division 1 (1) The Code Case damping should be used completely and consistently, if it is used at all. (For equipment other than piping, the damping values specified in RG 1.61, “Damping Values for Seismic Design of Nuclear Power Plants” (Ref. 12), should be used.) (2) The damping values specified may be used only in those analyses in which current seismic spectra and procedures have been employed. Such use is to be limited only to response spectral analyses [similar to that used in the study supporting its acceptance, NUREG/CR-3526, “Impact of Changes in Damping and Spectrum Peak Broadening on the Seismic Response of Piping Systems” (Ref. 13)]. The acceptance of the use with other types of dynamic analyses (e.g., time-history analyses or independent support motion method) is pending further justification. (3) When used for reconciliation work or for support optimization of existing designs, the effects of increased motion on existing clearances and online mounted equipment should be checked. (4) This Code Case is not appropriate for analyzing the dynamic response of piping systems using supports designed to dissipate energy by yielding (i.e., the design of which is covered by Code Case N-420). (5) This Code Case does not apply to piping in which stress corrosion-cracking has occurred unless a case-specific evaluation is made and is reviewed by the NRC staff. 5/5/00 N-430 Alternative Requirements for