United States Nuclear Regulatory Commission - Protecting People and the Environment


LICENSEE: CONSOLIDATED EDISON CO. OF N.Y./NEW

SITE: INDIAN POINT 2                        EN NUMBER:34713

DOCKET:  05000247                        EVENT DATE: 08-29-98

RX TYPE:  PWR                            EVENT TIME: 00:00

VENDORS:  W-4-LP                        NOTIFY DATE: 08-29-98

EMERGENCY CLASS: N/A  REGION: 1 STATE: NY      TIME: 17:12

OPS OFFICER: BOB STRANSKY             

10 CFR SECTION: CCCC  21.21               UNSPECIFIED PARAGRAPH

UNIT  SCRAM   RX   INIT  INITIAL MODE     CURR   CURRENT MODE

      CODE   CRIT  PWR                    PWR

 2    N       N      0   HOT SHUTDOWN       0   HOT SHUTDOWN   



10 CFR PART 21 REPORT REGARDING BINDING OF WESTINGHOUSE DB-50    

CIRCUIT BREAKERS                                                 

                                                                 

"AFTER COMPLETION OF SURVEILLANCE TEST PMT-170 AUXILIARY         

FEEDWATER PUMP (AFWP) ACTUATION FUNCTIONAL TEST, OPERATIONS MADE 

AN ATTEMPT TO START 21 AFWP FROM CCR CONTROL SWITCH. THE BREAKER 

DID NOT CLOSE.                                                   

                                                                 

"DURING STEP BY STEP INVESTIGATION AND INSPECTION, IT WAS        

DETERMINED THAT:                                                 

    (1) THE INERTIA LATCH FAILED TO RESET TO ITS NORMAL POSITION 

TO ENABLE                                                        

        THE OPERATING MECHANISM CLOSING THE BREAKER. (THE VISUAL 

INSPECTION                                                       

        FOUND THE INERTIA LATCH TO BE IN A POSITION TO PRECLUDE  

THE                                                              

        OPERATING MECHANISM FROM CLOSING THE BREAKER.)           

    (2) THE INERTIA LATCH INITIALLY WAS BINDING SEVERELY. AFTER  

        MANIPULATION OF THE LATCH THE FRICTION DECREASED TO A    

POINT WHERE                                                      

        THE MOVEMENT WAS NORMAL. WHEN THE LATCH WAS MOVED AXIALLY

TOWARD                                                           

        THE SNAP RING IT WOULD BIND AT THAT POINT.               

    (3) THE CAUSE OF THE FAILURE WAS SPALLING OR BREAKING-AWAY OF

SURFACE                                                          

        COATING ON THE PIVOT PIN AND POSSIBLY THE BUSHING (PIVOT 

PIN HOLE)                                                        

        OF THE INERTIA LATCH. THE FRAGMENTS OF THE COATING       

ACCUMULATED ON                                                   

        THE SURFACES OF THE PIN AND THE BUSHING IN DISCREET      

LOCATIONS,                                                       

        REDUCED THE CLEARANCE BETWEEN THE PIVOT PIN AND THE      

BUSHING. THE                                                     

        REDUCTION IN CLEARANCE RESULTED IN BINDING OF THE INERTIA

LATCH.                                                           

        THE INERTIA LATCH BINDING PREVENTED THE LATCH TO RESET IN

ITS                                                              

        NORMAL POSITION AND PREVENTED THE BREAKER FROM CLOSING.  

THE                                                              

        DIMENSIONS OF THE 21 AUXILIARY FEED PUMP BREAKER INERTIA 

LATCH PIN                                                        

        AND PIVOT PIN HOLE [BUSHING] WERE FOUND TO BE NOMINAL    

0.375" AND                                                       

        0.376" RESPECTIVELY.)                                    

                                                                 

"THE EXAMINATION OF THE COATING ON THE SHAFT PIN CLEARLY SHOWED  

THAT THE COATING WAS BREAKING AWAY FROM THE SURFACE. THE DAMAGE  

MAY HAVE BEEN INITIATED DURING TREATMENT WITH THE EMERY CLOTH AS 

PART OF THE CUSTOM FITTING PROCESS. HOWEVER IT APPEARS, THAT     

DURING SERVICE, MATERIAL WAS DISLODGED FROM THE SURFACES. THE    

VISUAL EXAMINATION INDICATES THAT THE QUALITY OF BONDING OF THE  

COATING ON THE SHAFT WAS INADEQUATE."                            

                                                                 

THE NRC RESIDENT INSPECTOR WILL BE INFORMED BY THE LICENSEE.     

                                                                 

                                                                 



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