ENS 44287: Difference between revisions
Jump to navigation
Jump to search
StriderTol (talk | contribs) Created page by program invented by Mark Hawes |
StriderTol (talk | contribs) Created page by program invented by StriderTol |
||
| Line 16: | Line 16: | ||
| event date = 06/11/2008 14:05 PDT | | event date = 06/11/2008 14:05 PDT | ||
| last update date = 06/12/2008 | | last update date = 06/12/2008 | ||
| title = Identification | | title = Identification of a Potential Issue with Accumulator Drain Valves | ||
| event text = On June 11, 2008 at 1405 PDT, licensed plant operators entered Technical Specification (TS) 3.0.3 on Units 1 and 2 due to identification of a potential ASCO solenoid valve failure that could initiate draining if the safety injection system accumulators following a small break Loss-of-Coolant-Accident (LOCA). | | event text = On June 11, 2008 at 1405 PDT, licensed plant operators entered Technical Specification (TS) 3.0.3 on Units 1 and 2 due to identification of a potential ASCO solenoid valve failure that could initiate draining if the safety injection system accumulators following a small break Loss-of-Coolant-Accident (LOCA). | ||
ASCO Model 8316 and 8321 pilot-operated solenoid valves over 12 years old are susceptible to a potential shuttle ('insert' per vendor documentation) malfunction. The malfunction is that with greater than 12 years of service and a loss of minimum operating pressure differential (MPOD), the shuttle (or insert) could reposition and fail to return to the desired position. This MPOD related reposition could result following instrument air pressure loss and subsequent restoration to containment following a postulated small break LOCA. Diablo Canyon Power Plant (DCPP) Units 1 and 2 each have four susceptible ASCO solenoid valve locations used as drain valves for each of the four safety injection system accumulators per unit. | ASCO Model 8316 and 8321 pilot-operated solenoid valves over 12 years old are susceptible to a potential shuttle ('insert' per vendor documentation) malfunction. The malfunction is that with greater than 12 years of service and a loss of minimum operating pressure differential (MPOD), the shuttle (or insert) could reposition and fail to return to the desired position. This MPOD related reposition could result following instrument air pressure loss and subsequent restoration to containment following a postulated small break LOCA. Diablo Canyon Power Plant (DCPP) Units 1 and 2 each have four susceptible ASCO solenoid valve locations used as drain valves for each of the four safety injection system accumulators per unit. | ||
Latest revision as of 21:14, 1 March 2018
| Where | |
|---|---|
Diablo Canyon  California (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| LER: | 05000275/LER-2008-001 Potential Accumulator Drain Line Actuation Following a LOCA Due to Solenoid Valve Failure |
| Time - Person (Reporting Time:+2.72 h0.113 days <br />0.0162 weeks <br />0.00373 months <br />) | |
| Opened: | Ken Johnston 23:48 Jun 11, 2008 |
| NRC Officer: | Pete Snyder |
| Last Updated: | Jun 12, 2008 |
| 44287 - NRC Website
| |
Diablo Canyon with 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |