Document: NRC Regulatory Guide
Document ID: 2e29f931-cdf2-4faa-a9e4-5d7cb237e57f
Document Type: regulatory_guide
Title: Service Limits and Loading Combinations for Class 1 Plate-and-Shell-Type Component Supports + HISTORY – HISTORY 10/2006 – DG-1169 , Proposed Revision 2
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0630/ML063000484.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.130
CFR Part: 
CFR Title: 

Content:
pset, emergency, and faulted plant conditions. Normal Plant Conditions. Those operating conditions that occur in the course of system startup, operation, hot standby, refueling, and shutdown, with the exception of upset, emergency, or faulted plant conditions. Upset Plant Conditions. Those deviations from the normal plant condition that have a high probability of occurrence. Emergency Plant Conditions. Those operating conditions that have a low probability of occurrence. Faulted Plant Conditions. Those operating conditions associated with postulated events of extremely low probability. Service Limits. Stress limits for the design of component supports, defined by Subsection NF of Section III of the ASME Boiler and Pressure Vessel Code. DG-1169, Page 5 Levels of Service Limits. Four levels of service limits — A, B, C, and D — defined by Section III of the ASME Boiler and Pressure Vessel Code for the design of loadings associated with different plant conditions for components and component supports in nuclear power plants. Operating-Basis Earthquake (OBE). Seismic event defined in Appendix A, “Seismic and Geologic Siting Criteria for Nuclear Power Plants,” to 10 CFR Part 100, “Reactor Site Criteria.” Safe-Shutdown Earthquake (SSE). Seismic event defined in Appendix A to 10 CFR Part 100. Specified Seismic Events. Operating-basis earthquake (OBE) and safe-shutdown earthquake (SSE), defined above. System Mechanical Loadings. The static and dynamic loadings developed by the system operating parameters — including deadweight, pressure, and other external loadings — and effects resulting from constraints of free-end movements, but excluding effects resulting from thermal and peak stresses generated within the component support. Ultimate Tensile Strength. Material property based on the engineering stress-strain relationship. Critical Buckling Strength. The strength at which lateral displacements start to develop simultaneously with in-plane or axial