ML17266A087

LER 79-022/03L-0 on 790627:during Periodic Surveillance, Testing Auxiliary Feedwater Pump Failed to Start.Cause Could Not Be Determined.Condensation in Steam Line May Have Delayed Starting Enough to Mislead Operator

ML17266A087
Person / Time
Site:	Saint Lucie
Issue date:	07/27/1979
From:	Schoppman M FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML17206A944	List: ML17206A943 ML17266A087
References
LER-79-022-03L, LER-79-22-3L, NUDOCS 7908070505
Download: ML17266A087 (3)

Text

NRC FORM 568 P.TT l'LICE')SEE EVENT REPORT U.S NUCLEAR RKCULATORY COMMISSION CONTROL SLCCX: I I I I)QI)PI EASE PRINT CR TYPS ALL RECUIREO INFOR7>>IATIONI 7I2 I 7I 7I9 REI>>CRT OA>>c Soecificatio re'IQ l!!!I"-Q'~lt I IQ~Q 1 a 9 UCLVSEE CQQE UCSHSE r VMS ER i5 9 L.C<<VSc TYDc<<O CON'T BZa"...;: m!0 I~O$O 61 OOCICET'IUMSC I Aa 63VENT Q*TE 14 15 EVENT OESCRIPTION ANO DROSABLE CONSSCUENCcS QIO During eriodic surveillance testin or~o 3 3 7.2..2 auxiliar feedwate I I pump was aligned to the"B" steam su 1.The stea,~o 5, ferred to the"A" side and t Subse uentl the steam supply was returned to the"B" side the umo started and the surveillance test performed satisfactoril

.This was the ei hth occur-~o a rence for the lC auxilia f e 1 0 1 5 5~OS"B" steam supply could not be determined at the time of the occurrence.

SYSTE34 CAVSE CAI'SE COMP, VAL>>lc CQQS CQQS 5USCQOE CCMDQHEHTCQQE SUS QOE SVSCQCc"0 LJS L'JS~0 LJS I-'IS 1 5 9 III 11 Ia Ia IS I9 3 5cCUEHTIAL OCCVRIIENCE REPORTIIEVI5IQH~LSRIRQ EVENT Y<<AR REPORT HQ, COOS TYPE il o, Gi>>i>>3'3>>~79~~02 2~<<'OI~L~i~0 31 Ta 24 2$'31'3 29 ACTION CUTUPS EDPECT>>SHUTCQ93H ATTACHM'CHT VDRQ>>4 PRIAIECcuD C 4DCHc73T TAKEN ACTION CN PLANT uETRQQ HOVRS~22 SV934ITTKO PCRMSVS SVDPUER 4*NUDA>>URER LIONS MS LJS~!IrIS Lcc MIS~I'G 34<<5 56 4O 41 42 43 CAUS-OSSCPIPTION ANO CORRKCilVIS AEONS QT o The cause for the 1C auxiliar f eedwater um f ailin t o start from the-Later pump operation indicates that condensation in the steam sutt, v line ma have delaved the start sufficientl to lead the believe the pump, failed to start when in actualit it was startin>>)'11 LOSS QD CR QAMAC Q FACILITY Q43 r YD'5 CESCRIDTIQH

~zQ2 NA~I 7 a I9~VSLIC:~;~~UEQ OESCPIPT:CH Q+giQA 2 O a~It N.A.Scho man 1 FACIUTY>>METI4QO QF 5".POYIER~CTIIER STATUS Q QISCQVERY 3~BQ33~OI 5 I 7 ID3 NA LB IQ3>>1 a 10.1$13~44 4$4I5 ACTIVITY CONTENT RELKASEO QD RELEASE WQVNT QF ACTIVITY QSS~i~~z Q22~z08 1 3 9 14 I I 44 4$P<<RSOVHEL SIIKISVRE5 VVMSER>>TYDS OESCPIPTIQH Q9~I)L000 OOQ33~ZQ33 I NA 1 9 3 13 DSRSOIIHEL INJURIES VI>>MS~R<<<<CSCIIIPTICIIQ

~ia~00 I 0 IQ3 NA 3 OISCQVERY QESCRIDTI H O4'2 0 erator Observ ion LOCATION QP RELSASE CI 30 20 39 NRC USa CF:LY)I)'))')))))

63 59 305/552-3802 1 a' Reportable Occurrence 335-79-22 Licensee Event Report Page t>>o Additional Cause Descri tion and Corrective Action During periodic surveillance testing the 1C auxiliary feedwater pump failed to start from the"B" steam supply.The pump was started successfully from the"A" steam supply and then started success-fully from the"B" steam supply.No cause for the failure to start on the first attempt could be determined at the time of occurrence.

Later pump operation indicates that the pump may not actuallj have failed to start.On 7-16-79 during operator training exercises the 1C auxiliary feedwater pump was started locally from the"B" steam supply header.An excessive quantity of water was observed issuing from the turbine exhaust, and the pump came up to speed at a much slower rate than normal.Further investi-gation'evealed that a recent change to operating procedure 0700022 changed normally open warm-up valves V8384 and V8385 to normally closed to agree with the system P and 1D.'Closing these, valves created a trap for conden-sation build-up upstream of the"B" steam supply valve MV08-13.It is now hypothesized that the build-up of condensation created a water turbine effect in the first seconds of the attempted pump start which resulted in a much slower rate of acceleration.

Normally, the pump reaches appcoximately 2000 rpm in 15-20 seconds and when the operator did not see any indication of rpm in that time frame, he manually tripped the pump.It is felt that the pu-..p was slowly accelerating as the water was passing through the turbine and the pump would have started had it not been tripped manually.Corrective action is to maintain the valves in a normally open configuration under OP 0010122.Review by the Facility Review Group has determined that maintaining the valves open does not jeopardize plant safety.Engineering will be requested to verify the FRG's findings.