ML17353A539

Ro:On 951221 & 29 3B EDG Failed Due to Loose Fitting on Fuel Oil Priming Pump Suction Line & Loose Fitting on Discharge Line.Leaking Fittings Tightened & All Fittings on Fuel Oil Suction Lines Verified Tight

ML17353A539
Person / Time
Site:	Turkey Point
Issue date:	01/19/1996
From:	Hovey R FLORIDA POWER & LIGHT CO.
To:	Ebneter S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
L-96-002, L-96-2, NUDOCS 9601300122
Download: ML17353A539 (6)

Text

CATEGORY' REGULATOR INFORMATION DISTRIBUTION TEM (RIDS)

(. ACCESSION NBR:9601300122 DOC.DATE: 96/01/19 NOTARIZED: NO DOCKET FACIL:50-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 AUTH. NAME AUTHOR AFFILIATION HOVEY,R.J. Florida Power a Light Co.

RECIP.NAME RECIPIENT AFFILIATION EBNETER,S.D. Region 2 (Post 820201)

SUBJECT:

RO:on 951221 & 29 3B EDG failed due to loose fitting on fuel oil priming pump suction line  !'oose fitting on discharge line. Leaking fittings tightened a all fittings on fuel oil suction lines verified tight.

DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.

NOTES:

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD2-1 PD 1 1 CROTEAU,R 1 1 INTERNAL: OD/SP, B 2 2 AEOD/SPD/RRAB 1 1 E CE.@ATE 1 1 NRR/DE/ECGB 1 1 NRR/DE/EELB 1 1 NRR/DE/EMEB 1 1 NRR/DRCH/HHFB 1 1 NRR/DRCH/HICB 1 1 NRR/DRCH/HOLB 1 1 NRR/DRCH/HQMB 1 1 NRR/DRPM/PECB 1 1 NRR/DSSA/SPLB 1 1 NRR/DSSA/SRXB 1 1 RES/DSIR/EIB 1 1 RGN2 FILE 01 1 1 EXTERNAL: L ST LOBBY WARD 1 1 LITCO BRYCE,J H 2 2 NOAC MURPHYiG.A 1 1 NOAC POOREiW. 1 1 NRC PDR 1 1 NUDOCS FULL TXT 1 1 NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN 5D-StEXT. 415-2083) TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 25 ENCL 25

p.p. 4000, Juno Beach, FL 33408 042D APL JAN18 ')995 L-96-002 10 CFR 550.36 Stewart D. Ebneter Regional Administrator, Region II U. S. Nuclear Regulatory Commission 101 Marietta St., N.W., Suite 2900 Atlanta, GA 30323 Mr. Stewart D. Ebneter:

Re: Turkey Point Unit 3 Docket No. 50-250 S ecial Re ort 3B Emer enc Diesel Generator Failure In accordance with Technical Specifications 4.8.1.1.3, the attached Special Report details the 3B Emergency Diesel Generator failures of December 21 and 29, 1995.

Should there be any questions on this information please contact us.

V ty ly yours, I'~E

/

fop Robert J. Hovey Vice President Turkey Point Plant CLM Attachment cc: USNRC, Document Control Desk, Washington D.C.

Thomas P. Johnson, Senior Resident Inspector, USNRC, Turkey Point Plant 960i300i22 'rr601.i9 PDR ADDCK 05000250 S PDR an FPL Group company

Attachment Page 1 of 3 SPECIAL REPORT 3B El'ERGENCY DIESEL GENERATOR FAILURE PURPOSE:

Technical Specification 4.8.1.1.3, requires the submittal of a special report to the NRC in the event of a diesel generator failure. The Technical Specification requires the report to include the information recommended in Regulatory Position C.3.b of Regulatory Guide 1.108, Revision 1, August, 1977.

BACKGROUND:

Florida Power and Light's (FPL) Turkey Point Nuclear Units 3 and 4 have two Emergency Diesel Generators (EDGs) for each unit. The Unit 3 EDGs were overhauled, and the Unit 4 EDGs installed, during the dual unit outage in 1990/1991.

On 12/21/95, the 3B EDG was out of service for an upgzade to its electrical circuit, Zn preparation for the post-modification test, Operations personnel attempted to run the electric fuel priming pump, to ensure fuel supply to the EDG prior to starting it. Although the pump appeared to run, it did not develop satisfactory discharge pressure. The pump was replaced, and operated satisfactorily. The post-modification test was then completed satisfactorily, and the EDG was restored to service. Although the EDG was out of service when the condition was discovered, the condition was considered an EDG failure in accordance with Regulatory Position C.2.a(9) of Regulatory Guide 1.108, Revision 1, August, 1977. Since this was the second failure in 20 starts, the EDG surveillance frequency was increased to weekly in accordance with Technical Specification 4.8.1.1.2.

Zn preparation for running the 3B EDG on 12/28/95, the electric fuel priming pump again did not develop satisfactory pressure. The pump sounded as if it were dry. The 3B pump took longer to coast down than the (properly operating) 3A EDG electric fuel priming pump. There was no abnormal noise associated with the operation of the 3B fuel priming pump, other than sounding dry. The pump was inspected for proper rotation, with satisfactory results. Two fittings were found wetted with fuel. The suction line was removed and found to be dzy, when it should have been filled with fuel. The fuel oil suction strainer was partially filled with fuel in the bowl. The fuel level was consistent with the level of the suction pipe in the strainer bowl. The suction strainer was clean. The suction piping was then placed in a container of fuel oil; the priming pump operated correctly, indicating that the pump was not the cause of the failure. The suction lines were then filled with fuel, and all pipe connections between the engine-driven fuel pump, the electric priming pump, and the skid tank were verified tight. The electzic fuel priming pump then performed satisfactorily.

Attachment Page 2 of 3 The two leaking fittings were located (1) between the fuel suction strainer and the electric priming pump, and (2) between the electric

.".riming pump and its associated check valve. Should either of these fittings leak, the fuel would drain from the pump, back into the skid tank.

The following discussion addresses each of the areas listed in Regulatory Position C.3.b of Regulatory Guide 1.108, Revision 1, August, 1977.

(1) DIESEL GENERATOR UNIT INVOLVED:

The 3B EDG may not have started due to lack of fuel in its suction line.

(2) IDENTIFY THE FAILURE AS BEING THE N-TH FAILURE IN THE LAST 100 VALID TESTS:

The failure count for the Unit 3 EDGs was transvalued to zero at the end of the dual unit outage, concurrent with the implementation of Turkey Point's Revised Technical Specifications and the dual unit outage overhaul. These failures were the fourth and fifth failures of the 3B EDG since the count was rezeroed, but one of these five was a non-valid failure.

(3) CAUSE OF FAILURE:

The cause of the 3B EDG failure was one loose fitting on the fuel oil priming pump suction line and one loose fitting on the discharge line, allowing fuel oil to drain back into the skid tank. The electric fuel priming pump would not prime with both fittings loose, and therefore would not develop pressure.

(4) CORRECT1VE MEASURES TAKEN:

The leaking fittings were tightened, and all fittings on the fuel oil suction lines were verified tight.

2. The EDG was tested satisfactorily after the electric fuel priming pump and suction lines were returned to service.

3. Operations personnel verified that the electric fuel priming pump will develop adequate pressure, on an increased frequency. Initially the verification was performed every two hours. The frequency was then gradually relaxed, based on continued satisfactory results. Presently the verification is being performed daily.

Attachment Page 3 of 3 (5) LENGTH OF TIME THE DIESEL GENERATOR WAS UNAVAILABLE:

The 3B EDG was unavailable for 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />, 15 minutes, from 0615 on 12/21/95 to 1350 on 12/22/95, but this unavailability was started as a planned outage to perform a modification. The first failure of the fuel priming pump was discovered at 1945 on 12/21/95, so 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br />, 5 minutes of the unavailability may be attributed to the failure. The EDG was unavailable for 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br />, 50 minutes, on 12/29/95, as a direct result of the aiz-bound fuel oil suction line.

(6) DEFINITION OF CURRENT SURVEILLANCE TEST INTERVAL:

Unless a trigger value is exceeded (2 failures in the last 20 valid tests, or 5 failures in the last 100 valid tests), the normal surveillance frequency is every 31 days. These are the second and third failures in the last 20 valid tests, and the fourth failure in the last 100 valid test. Therefore, the surveillance interval for the 3B EDG is weekly.

(7) VERIFICATION OF TEST INTERVAL IN CONFORMANCE WITH REGULATORY POSITION C.2.d:

The test interval is in conformance with the requirements of Turkey Point Technical Specifications Table 4.8-1.