Document: NUREG-0800
Document ID: 42e7682f-df25-4a6a-94f4-7d44ea029702
Document Type: srp
Title: STEAM SYSTEM PIPING FAILURES INSIDE AND OUTSIDE OF CONTAINMENT
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070677.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.1.5
CFR Part: 
CFR Title: 

Content:
teady state, and transient stresses; and the sizes of flaws. GDC 31 is applicable to this section because the reviewer evaluates steam system piping failures, both inside and outside containment, that could cause transient conditions with a potentially harmful effect on the reactor coolant pressure boundary. A steam system piping break can result in a rapid decrease in reactor coolant temperature and steam generator pressure, placing undue stress on the reactor coolant pressure boundary. This potential problem could be aggravated by a pressurization of the primary system when the emergency core cooling system is activated. The amount of stress to the reactor coolant pressure boundary depends on the severity of the transient. The severity of the transient is assessed by the applicant in the SAR and is reviewed by the staff in accordance with this SRP section. Meeting the requirements of GDC 31 provides assurance that a transient initiated by a steam system pipe break will not result in an unacceptable stress on the reactor coolant pressure boundary.44 4. Compliance with GDC 35 requires a system that will provide abundant emergency core cooling. The system safety function shall be to transfer heat from the reactor core after any loss of reactor coolant at a rate ensuring that (a) fuel and clad damage interfering 15.1.5-9 DRAFT Rev. 3 - April 1996 with continued effective core cooling is prevented and (b) clad metal-water reaction is limited to negligible amounts. GDC 35 is applicable to this section because the reviewer evaluates steam system piping failures, both inside and outside containment, that could cause transient conditions with the potential to challenge the emergency core cooling system. During a steam system piping break, excessive steam loss will result in a rapid reduction of reactor coolant temperature and steam generator pressure. A subsequent reactor trip can further reduce the primary system pressure, producing a void within the pressure vessel and