25 novembre 2017
Les opérateurs ont constaté la tombée des deux pompes ainsi qu’une baisse de vde niveau dans les générateurs de vapeur. La tombée du réacteur a entrainé la tombée de la turbine. Les deux pompes auxiliaires ont démarré suite à la tombée des pompes principales. Le réacteur est en mode 3 et les procédures d’urgence ont été stoppées. La chaleur résiduelle du coeur est retirée par le condenseur principal via les vannes de dérivation.
Type : PWR - Puissance : 3 458 MWth - Première divergence : 3 / 1993 -
Available in english only
Event Number : 53091
Facility : COMANCHE PEAK
Unit : [2] - RX Type : [2] W-4-LP
Event Date : 11/25/2017
Event Time : 20:25 [CST]
Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Initial PWR : 100 % Current PWR : 0 %
Event Text :
MANUAL REACTOR TRIP DUE TO LOSS OF MAIN FEED WATER
"At time 2025 [CST] on 11/25/17, Unit 2 reactor was manually tripped due to a loss of all Main Feedwater. Operators observed both Main Feed Pumps tripped and SG [Steam Generator] levels decreasing, resulting in the direction for a manual reactor trip. The reactor trip actuated a turbine trip, both Motor Driven Auxiliary Feedwater Pumps started on the loss of both Main Feed Pumps, and Steam Generator Lo Lo levels started the Turbine Driven Auxiliary Feedwater Pump. All systems responded as expected. There was no work in progress at the time of the incident.
"Currently Unit 2 is being maintained in Hot Standby (Mode 3) in accordance with Integrated Plant Operating Procedure IP0-0078 and the Emergency Response Guideline Procedure Network has been exited. Decay Heat is being rejected to the Main Condenser via Steam Dump Valves."
The licensee has notified the NRC Resident Inspector.
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2017/20171127en.html