ML20168A564
| ML20168A564 | |
| Person / Time | |
|---|---|
| Site: | Kewaunee  |
| Issue date: | 06/16/2020 |
| From: | Christopher Hunter NRC/RES/DRA/PRB |
| To: | |
| Littlejohn J (301) 415-0428 | |
| References | |
| LER 1979-002-00 | |
| Download: ML20168A564 (4) | |
Text
B-587 PRECURSOR DESCRIPTION AND DATA NSIC Accession Number: 147399 Date: March 22, 1979
Title:
Both Diesel Generators Unavailable at Kewaunee The failure sequence was:
- 1. With the reactor at full power, diesel generator lB was removed from service for maintenance.
- 2. During the testing of diesel 1A, manual speed control was lost due to excessive wear to the bronze pinion in the syncho-notor gear housing.
The pinion damage was caused by improper gear alignment and failure of a governor limit switch.
Corrective action:
The pinion and limit switch were replaced and adjusted and the diesel generator was tested and returnr4 to service.
Design purpose of failed system or component:
The diesel generators provide power to safety-related equipment when offsite power and the unit generator are unavailable.
2 Unavailability of system per WASH 1400: *Emergency power: 1 x 10- 1D Unavailability of component per WASH 1400: *Diesel generator: 3 x 10-2 /D Unavailabilities are in units of per demand D-1. Failure rates are in units of per hour HR-1 .
Reactor at Power Diesel Generator Potential and Diesel Gen- lA Fails to Run Severe erator lB Removed Due to Loss of Core From Service for Manual Speed Damage Maintenance Control - A Result of a Worn Pinion in the Synchro-Motor Gear Housing and a Failed Limit Switch No - No loop td' No NSIC 147399 - Actual Occurrence for Both Diesel Generators Unavailable at Kewaunee
/
Loss of Turbine Emer- Auxiliary PORV PORV or High Long Potential Sequence Offsite Generator gency Feedwater and Demanded PORV Isola- Pressure Term Severe No.
Power Runs Back Power Secondary tion Valve Injection Core Core and Assumes Heat Removal Clo::,ure Cooling Damage House toads
_______________________________________No No 2 No 3 Yes 4 Yes 5 No 6 00 No 7 Yes 8 Yes 9 No 10 Yes 11
-LIU 12 13 NSIC 147399 - Sequence of Interest for Both Diesel Generators Unavailable at Kewaunee
- Not included in operating procedures
B-590 CATEGORIZATION OF ACCIDENT SEQUENCE PRECURSORS NSIC ACCESSION NUMBER: 147399 DATE OF LER: March 22, 1979 DATE OF EVENT: February 21, 1979 SYSTEM INVOLVED: Emergency power COMPONENT INVOLVED: Diesel generator CAUSE: Excessive wear on pinion In synchro-gear motor housing plus failed limit switch SEQUENCE OF INTEREST: Loss of offsite power ACTUAL OCCURRENCE: Unavailability of two diesel generators while at power REACTOR NAME: Kewaunee DOCKET NUMBER: 305 REACTOR TYPE: PWR DESIGN ELECTRICAL RATING: 535 M~We REACTOR AGE: 5.0 yr VENDOR: Westinghouse ARCHITECT-ENGINEERS: Flour Power OPERATORS: Wisconsin Public Service Corp.
LOCATION: 27 miles East of Green Bay, Wisconsin DURATION: 4(a) hours PLANT OPERATING CONDITION: 100% power SAFETY FEATURE TYPE OF FAILURE: (a) inadequate perform nce; (b) failed to start; (c) made inoperable; failed to run DISCOVERY METHOD: Testing COMMENT: