11 juillet 2017
Ce système, non doublé, d’indication du flux de la soupape d’injection de sécurité haute pression du cœur étant défaillant, il aurait empêché l’accomplissement d’une fonction de sécurité en cas de problème. Le dépannage est en cours pour déterminer la cause et corriger la situation.
Type : BWR Mark 2 - Puissance : 3 486 MWth - Première divergence : 1 / 1984 -
Available in english only
Event Number : 52848
Facility : COLUMBIA GENERATING STATION
State : WA Unit : [2] RX Type : [2] GE-5
Event Date : 07/11/2017 - Event Time : 07:50
Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Initial PWR : 100 % Current PWR : 100 %
Event Text
FLOW INDICATING SWITCH FOR HIGH PRESSURE CORE SPRAY UNRELIABLE INDICATION
"This report is being made pursuant to 10 CFR 50.72(b)(3)(v)(D) as an event or condition that could have prevented fulfillment of a safety function. On July 11th, 2017, it was discovered that the flow indicating switch for the high pressure core spray (HPCS) minimum flow valve was providing unreliable indication. There was no flow through the line at the time the condition was discovered. This switch provides the flow signal to the HPCS minimum flow valve logic.
"The switch was declared inoperable and the required actions of Technical Specification 3.3.5.1 were entered. This condition could have prevented the HPCS system, a single train safety system, from performing its specified safety function. Troubleshooting is underway to determine the cause of and correct the condition."
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2017/20170712en.html