Document: NUREG-0800
Document ID: 90914152-fc84-4413-a5f5-aa75efd21205
Document Type: srp
Title: TURBINE MISSILES
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0636/ML063600395.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.5.1.3
CFR Part: 
CFR Title: 

Content:
ith tables of missile generation probabilities versus time (inservice visual, surface, and 3.5.1.3-6 Revision 3 - March 2007 volumetric rotor inspection interval for design speed failure and inservice valve testing interval for destructive overspeed failure) for each turbine. These probabilities should be used to establish inspection and test schedules that meet NRC safety objectives. TABLE 3.5.1.3-1 PROBABILITY OF TURBINE FAILURE RESULTING IN THE EJECTION OF TURBINE ROTOR (OR INTERNAL STRUCTURE) FRAGMENTS THROUGH THE TURBINE CASING (P1 ) AND RECOMMENDED LICENSEE ACTIONS Case PROBABILITY PER YEAR FOR A FAVORABLY ORIENTED TURBINE PROBABILITY PER YEAR FOR AN UNFAVORABLY ORIENTED TURBINE RECOMMENDED LICENSEE ACTION A P1 < 10-4 P1 < 10-5 This condition represents the general, minimum reliability requirement for loading the turbine and bringing the system on line. B 10-4 < P1 < 10-3 10-5 < P1 < 10-4 If this condition is reached during operation, the turbine may be kept in service until the next scheduled outage, at which time the licensee must take action to reduce P1 to meet the appropriate Case A criterion before returning the turbine to service. C 10-3 < P1 < 10-2 10-4 < P1 < 10-3 If this condition is reached during operation, the turbine must be isolated from the steam supply within 60 days, at which time the licensee must take action to reduce P1 to meet the appropriate Case A criterion before returning the turbine to service. D 10-2 < P1 10-3 < P1 If this condition is reached during operation, the turbine must be isolated from the steam supply within 6 days, at which time the licensee must take action to reduce P1 to meet the appropriate Case A criterion before returning the turbine to service. 5. Applicants are expected to commit to the following program if turbines are obtained from manufacturers that have not submitted, or received NRC approval for, reports describing their methods and procedures for calculating turbine missile generation probabilities: