Part 21 Report - 1997-280
LICENSEE: COMMONWEALTH EDISON CO.
SITE: ZION 1 2 EN NUMBER:32037
DOCKET: 05000295 05000304 EVENT DATE: 03-27-97
RX TYPE: PWR PWR EVENT TIME: 13:55
VENDORS: W-4-LP W-4-LP NOTIFY DATE: 03-27-97
EMERGENCY CLASS: N/A REGION: 3 STATE: IL TIME: 15:55
OPS OFFICER: HENRY BAILEY
10 CFR SECTION: CDEG 21.21(c)(3)(i) DEFECTS/NONCOMPLIANCE
UNIT SCRAM RX INIT INITIAL MODE CURR CURRENT MODE
CODE CRIT PWR PWR
1 N N 0 COLD SHUTDOWN 0 COLD SHUTDOWN
2 N N 0 COLD SHUTDOWN 0 COLD SHUTDOWN
PART 21 NOTIFICATION BY VENDOR. COOPER-BESSEMER EMERGENCY
DIESELS
ON JANUARY 27, 1997 COMMONWEALTH EDISON COMPANY IDENTIFIED A
SIGNIFICANT DROP IN CRANKCASE LUBE OIL LEVEL IN ONE OF THE
COOPER-BESSEMER EMERGENCY DIESEL GENERATORS. SUBSEQUENT
INVESTIGATION REVEALED THAT A CRACK HAD DEVELOPED IN THE CYLINDER
LINER WALL ALLOWING JACKET WATER TO ENTER THE COMBUSTION
CHAMBER.
THIS RESULTED IN A FAILED PISTON. UPON REVIEW OF THE FAILED
PISTON IT WAS NOTED THAT THE PISTON CROWN THICKNESS IN THE AREA
OF FAILURE WAS BELOW DRAWING SPECIFICATIONS.
THIS IS THE ONLY KNOWN FAILURE OF SUBJECT LINER. THIS LINER
DESIGN IS IN USE ON "EARLY" KSV ENGINES IN USE AT THE ZION
STATION AND AT THE COOPER NUCLEAR STATION. FAILURE OF THE PISTON
WAS A DIRECT RESULT OF THE LINER FAILURE. FINITE ELEMENT ANALYSIS
IS BEING CONDUCTED BY COOPER-BESSEMER TO DETERMINE ACCEPTABLE
MINIMUM THICKNESS FOR THE PISTON CROWN SECTION. THIS PISTON
EVALUATION COULD AFFECT THE FOLLOWING KSV USERS: PALO VERDE,
BRAIDWOOD, BYRON, ZION, WATERFORD III, SOUTH TEXAS, COOPER, NINE
MILE POINT 2, AND SUSQUEHANNA. IT IS EXPECTED THIS EVALUATION
WILL BE COMPLETED BEFORE MAY 28, 1997.
Page Last Reviewed/Updated Wednesday, March 24, 2021