Document: NUREG-0800
Document ID: 621763b9-bd48-4ded-8c42-b942a23a06d4
Document Type: srp
Title: – 15.2.5
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070680.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.2.1
CFR Part: 
CFR Title: 

Content:
am lines are less than 90% open, the reactor pressure is above 600 psi 4140 kPa (600 psi),9 and the reactor mode switch is in the RUN position. The effect of MSIV closure is to limit steam flow to the turbine. The results are similar to those discussed in item 1, above, but tend to be less severe since the MSIV closure time is much longer than that of the TCVs. 5. Steam Pressure Regulator Failure Steam pressure regulator failure in a closed position yields a transient similar to the transients discussed above. Generally, because the rate of change of system parameters is slower for a steam pressure regulator failure, a less severe transient results. 15.2.1-3 DRAFT Rev. 2 - April 1996 The review of the transients described above includes the sequence of events, the analytical models, the values of parameters used in the analytical models, and the predicted consequences of the transients. The sequence of events described in the SAR analysis is reviewed by RSBSRXB in consultation with the Instrumentation and Control Systems Branch (ICSBHICB). The RSBSRXB reviewer 10 concentrates on the assumptions used for the reactor protection system, the engineered safety systems, and operator action to secure and maintain the reactor in a safe condition. The analytical methods are reviewed by RSBSRXB to ascertain that all mathematical models and computer codes have been previously reviewed and accepted by the staff. If a referenced analytical method or code has not been previously reviewed, the RSBSRXB reviewer requests initiation of a generic evaluation of the new analytical model or code by RSBSRXB.or the Core Performance Branch (CPB), as appropriate.11 The predicted results of the transient analyses are then reviewed to assureensure that the 12 consequences meet the acceptance criteria given in subsection II, below. Further, the results of the analyses are reviewed to ascertain that the predicted values of pertinent system parameters are within expected ranges for the type and