Document: NUREG-0800
Document ID: c9c204f0-a162-491c-8c25-ee0418212f29
Document Type: srp
Title: PRESSURE-TEMPERATURE LIMITS, UPPER-SHELF ENERGY, AND PRESSURIZED
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0703/ML070380185.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.3.2
CFR Part: 
CFR Title: 

Content:
mperature must be higher than that required for inservice hydrostatic testing. In addition, the P-T relationship must provide at least a 22 EC (40 EF) margin over that required for heatup and cooldown operations. 2. Upper-Shelf Energy A. Applicable Regulations, Codes, and Basis Documents. Appendix G to 10 CFR Part 50 requires that reactor vessel beltline materials have a Charpy USE value in the transverse direction for base material and along the weld for weld material according to the ASME Code of no less than 102 J (75 ft-lb) initially and must maintain a Charpy USE value throughout the life of the vessel of no less than 68 J (50 ft-lb), unless it is demonstrated in a manner approved by the 5.3.2-6 Revision 2 - March 2007 Director, Office of Nuclear Reactor Regulation, that lower values of Charpy USE will provide margins of safety against fracture equivalent to those required by Appendix G of Section XI of the ASME Code. B. Upper-Shelf Energy Requirements. Appendix G to 10 CFR Part 50 contains the following USE requirements: i. Initially, the USE value in the transverse direction for base material and along the weld must not be less than 102 J (75 ft-lb). ii. Charpy USE throughout the life of the vessel must be maintained at no less than 68 J (50 ft-lb), unless it is demonstrated in a manner approved by the Director, Office of Nuclear Reactor Regulation, that lower values of Charpy USE will provide margins of safety against fracture equivalent to those required by Appendix G of Section XI of the ASME Code. 3. Pressurized Thermal Shock A. Applicable Regulations, Codes, and Basis Documents. Projected values of RTPTS must be determined for PWR reactor vessel beltline materials in accordance with 10 CFR 50.61. For RTPTS values projected to exceed the screening criteria, safety analyses must be provided that include proposed flux reduction programs or other corrective actions to prevent potential PTS-related failure of the reactor vessel if continued plant operation