Document: NRC Regulatory Guide
Document ID: 10f3c2aa-ada2-4132-8d49-7867458d81a7
Document Type: regulatory_guide
Title: Design Limits and Loading Combinations for Metal Primary Reactor Containment System Components + HISTORY - HISTORY 10/2006 – DG-1158 , Proposed Revision 1
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0630/ML063000278.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.57
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CFR Title: 

Content:
Code, Section III, “Nuclear Components,” Division 1, including that part of the Summer 2003 Addenda. DG-1158, Page 4 The design conditions and functional requirements of components that provide a pressure boundary for the primary reactor containment function should be reflected in the application of appropriate design limits (e.g., stress or strain limits) for the most adverse combination of loadings to which these components might be subjected. For components constructed in accordance with Subsection NE (Code Class MC) of the Code, the NRC requires provision of a design specification, which stipulates the design requirements (e.g., the mechanical and operational loadings) for the components. In Appendix B to the Code, entitled “Owner’s Design Specifications,” Paragraph B-2125, “Load Combinations,” states, “In order to provide a complete definition of service loads, the combination of specific events must be considered. Since these combinations are a function of specific systems which make up a part of a specific type of nuclear facility, this section does not directly address service loads other than to provide different stress limits for various loadings.” To further provide a consistent basis for the design of metal containment system components, this guide delineates acceptable design limits for appropriate combinations of loadings. The intent is to address only the most adverse combinations of loadings resulting from those events or conditions identified herein (e.g., those combinations of loadings that result in the limiting or controlling design condition). These loadings are associated with conditions for which the containment function is required, in combination with specified seismic events producing possible mechanisms for failure that could affect the function and/or integrity of structures, systems, and components important to safety. Included in the latter are the loadings associated with the vibratory motion of the safe-shutdown