Document: NUREG-0800
Document ID: d05488b9-f265-4d28-a268-f840c0469a1b
Document Type: srp
Title: - 15.3.4-7
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070550012.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.3.3
CFR Part: 
CFR Title: 

Content:
Revision 3 - March 2007 coolant pressure boundary or on the capability for core cooling. The analyses must be independently reviewed by the staff in accordance with this SRP section. Meeting the requirements of GDC 27 and GDC 28 provides a level of assurance that a transient initiated by an RCP rotor seizure or shaft break will not result in (a) unacceptable stress on the reactor coolant pressure boundary or (b) a reduction in the capability of the core cooling or reactivity control systems to perform their design safety functions. 3. Compliance with GDC 31 requires that, under the stress of operating, maintenance, testing, and postulated accident conditions, the reactor pressure boundary shall be designed with sufficient margin to ensure that (a) the boundary behaves in a non-brittle manner and (b) the probability of rapidly propagating fracture is minimized. The design shall reflect consideration of service temperatures and other boundary material variables under operating, maintenance, testing, and postulated accident conditions. The design will also address such issues as the uncertainties of determining material properties; the effects of irradiation on material properties; residual, steady state, and transient stresses; and the sizes of flaws. GDC 31 is applicable to this section because the reviewer evaluates two events (RCP rotor seizure and shaft break) that could result in transient conditions having the potential for adversely affecting the reactor coolant pressure boundary. Loss of a reactor cooling pump will cause a rapid reduction in coolant flow through the core and, consequently, an increase in temperature and pressure. The amount of stress to which the reactor coolant pressure boundary is subjected depends on the severity of the transient. The severity of the transient is assessed by the applicant in the SAR and reviewed by the staff in accordance with this SRP section. Meeting the requirements of GDC 31 provides a level of assurance that a