ENS 51982: 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 = 06/05/2016 12:27 EDT | | event date = 06/05/2016 12:27 EDT | ||
| last update date = 06/05/2016 | | last update date = 06/05/2016 | ||
| title = Reactor Trip | | title = Reactor Trip and Eccs Actuation Caused by Turbine Governor Valve Failure | ||
| event text = On June 5, 2016 at 1227 Eastern Daylight Time (EDT), Watts Bar Nuclear Plant (WBN) Unit 2 was in MODE 1 at approximately 12.5% power when a safety injection actuation occurred, followed by an automatic reactor protection system (RPS) trip. Preliminary data suggests that the #1 high pressure turbine governor valve failed open causing a steam header pressure rate of decrease safety injection [SI] actuation signal. As designed, the safety injection actuation caused both trains of the shared Emergency Gas Treatment System (EGTS) to align to Unit 2, requiring WBN Unit 1 to enter Technical Specification (TS) LCO 3.0.3 at 1227 [EDT]. Also as designed, Unit 1 annulus pressure momentarily increased, causing operation personnel to enter LCO 3.6.15 Condition B at 1240 [EDT]. At 1242 [EDT], after annulus pressure normalized, operations personnel exited LCO 3.6.15. At 1245 [EDT], Operations personnel secured safety injection and Unit 2 was stabilized in MODE 3 at normal operating pressure and temperature. By 1349 [EDT], Unit 1 Operations personnel had restored both trains of EGTS to standby readiness, and exited TS 3.0.3. No primary safety barriers (RCS, containment and fuel clad) were challenged and no primary or secondary safety or relief valves actuated during the event. The Unit 2 plant trip was uncomplicated and safety equipment operated as expected. | | event text = On June 5, 2016 at 1227 Eastern Daylight Time (EDT), Watts Bar Nuclear Plant (WBN) Unit 2 was in MODE 1 at approximately 12.5% power when a safety injection actuation occurred, followed by an automatic reactor protection system (RPS) trip. Preliminary data suggests that the #1 high pressure turbine governor valve failed open causing a steam header pressure rate of decrease safety injection [SI] actuation signal. As designed, the safety injection actuation caused both trains of the shared Emergency Gas Treatment System (EGTS) to align to Unit 2, requiring WBN Unit 1 to enter Technical Specification (TS) LCO 3.0.3 at 1227 [EDT]. Also as designed, Unit 1 annulus pressure momentarily increased, causing operation personnel to enter LCO 3.6.15 Condition B at 1240 [EDT]. At 1242 [EDT], after annulus pressure normalized, operations personnel exited LCO 3.6.15. At 1245 [EDT], Operations personnel secured safety injection and Unit 2 was stabilized in MODE 3 at normal operating pressure and temperature. By 1349 [EDT], Unit 1 Operations personnel had restored both trains of EGTS to standby readiness, and exited TS 3.0.3. No primary safety barriers (RCS, containment and fuel clad) were challenged and no primary or secondary safety or relief valves actuated during the event. The Unit 2 plant trip was uncomplicated and safety equipment operated as expected. | ||
Unit 2 is stable in Mode 3 at normal operating temperature and pressure, in normal shutdown power alignment. Unit 1 is stable in Mode 1 at 100% power. | Unit 2 is stable in Mode 3 at normal operating temperature and pressure, in normal shutdown power alignment. Unit 1 is stable in Mode 1 at 100% power. |
Latest revision as of 21:45, 1 March 2018
Where | |
---|---|
Watts Bar ![]() Tennessee (NRC Region 2) | |
Reporting | |
10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge 10 CFR 50.72(b)(2)(iv)(B), RPS Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
LER: | 05000391/LER-2016-004 |
Time - Person (Reporting Time:+-0.08 h-0.00333 days <br />-4.761905e-4 weeks <br />-1.09584e-4 months <br />) | |
Opened: | Michael Bottorff 16:22 Jun 5, 2016 |
NRC Officer: | Dong Park |
Last Updated: | Jun 5, 2016 |
51982 - NRC Website
| |