Document: NUREG-0800
Document ID: c5cd8519-169f-4fec-9d25-9ddb3ba73f52
Document Type: srp
Title: RESIDUAL HEAT REMOVAL (RHR) SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550002.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.7
CFR Part: 
CFR Title: 

Content:
viewer verifies that automatic closure interlocks for the RHR suction isolation valves, if provided, are designed in such a manner as to minimize inadvertent valve closure during system operation (new PWR applicants only). 21. The reviewer verifies that the applicant has reviewed its RHR system design configurations to identify any piping connected to the RCS that could be subjected to temperature distributions that could result in unacceptable thermal stresses. This review should consider the potential for thermal stratification, thermal cycling, and thermal fatigue, given the RHR system configuration. The reviewer verifies that appropriate action has been taken, where such piping is identified, to ensure that the piping will not be subjected to unacceptable thermal stresses (see NRC Bulletin 88-08). This review should focus on RHR system configurations; the organization responsible for mechanical engineering reviews under SRP Section 3.9.3 reviews the stress analysis and ensures that it conforms to the American Society of Mechanical Engineers Boiler and Pressure Vessel Code. 5.4.7-13 Revision 4 - March 2007 22. The NRC states its regulatory position with respect to minimizing the potential for an intersystem LOCA in advanced or evolutionary light-water reactors in SECY-90-016 and SECY-93-087 and their associated staff requirements memoranda. In keeping with that position, the reviewer will verify that, to the extent practical, the RHR system for advanced or evolutionary light-water reactors is designed to an ultimate rupture strength at least equal to the normal RCS operating pressure. All elements of the RHR system are to be considered (e.g., instrument lines, pump seals, heat exchanger tubes, valve bonnets) The licensee should provide justification for elements not designed to an ultimate rupture strength at least equal to the normal RCS operating pressure. 23. Some advanced light-water reactor (ALWR) designs make extensive use of passive systems to meet