ML17345A162

LER 88-005-00:on 880415,loss of Flowpath from Boric Acid Storage Tanks to RCS Occurred.Caused by Loose Screw in Motor/Pump Coupling.Boric Acid Transfer Pump 4A Realigned to Provide Boric Acid Flow Path to Unit 3.W/880513 Ltr

ML17345A162
Person / Time
Site:	Turkey Point
Issue date:	05/13/1988
From:	Conway W, Salamon G FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
L-88-225, LER-88-005, LER-88-5, NUDOCS 8805230009
Download: ML17345A162 (6)

Text

AC CELE RATED DISHBUTION DEMON STRA'+3N SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

.i ACCESSION NBR:8805230009 DOC.DATE: 88/05/13 NOTARIZED: NO DOCKET FACIL:50-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 AUTH. NAME AUTHOR AFFILIATION SALAMON,G. Florida Power & Light Co.

CONWAY,W.F. Florida Power & Light Co.

RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 88-005-00:on 880415,loss of flowpath from boric acid storage tanks to RCS due to coupling failure.

W/8 ltr.

DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE:

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

NOTES ID RECIPIENT CODE/NAME PD2-2 LA COPIES LTTR ENCL 1 1 ID PD2-2 RECIPIENT CODE/NAME PD.

COPIES LTTR ENCL 1 1 j

A EDISON,G 1 1 INTERNAL ACRS MICHELSON 1 1 ACRS MOELLER 2 2 AEOD/DOA 1 1 AEOD/DS P/NAS 1 1 AEOD/DSP/ROAB 2 2 AEOD/DSP/TPAB 1 1 ARM/DCTS/DAB 1 1 DEDRO 1 1 NRR/DEST/ADS 7E 1 0 NRR/DEST/CEB 8H 1 1 NRR/DEST/ESB 8D 1 1 NRR/DEST/ICSB 7 1 1 NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1 1 NRR/DEST/PSB 8D 1 1 NRR/DEST/RSB 8E 1 1 NRR/DEST/SGB 8D NRR/DLPQ/QAB 10 NRR/DREP/RAB 10 1

1 1

1 1

1 NRR/DLPQ/HFB 10 NRR/DOEA/EAB NRR/DREP/RPB 10 ll 1 1

2 1

2 1

• NRR/DRIS/SIB 9A 1 1 NR~~S ILRB12 1 1 NUDOCS-ABSTRACT 1 1 G FILE 02 1 1 RES TELFORD i J 1 1 RES IB 1 1 RES/DRPS DEPY 1 1 RGN2 FILE Ol 1 1 EXTERNAL EG&G WILLIAMSi S 4 4 FORD BLDG HOY i A 1 1 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC HARRIS,J 1 1 NSIC MAYS,G 1 1 h

TOTAL NUMBER OF COPIES REQUIRED: LTTR 46 ENCL 45

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Form 365 t LICENSEE EVENT REPORT (LER) v.S. NUCLEAR REOULATORY COMMISSION DOCKET NUMBER (2)

APPROVED OMB NO. 3150-0104

'"""'N'v PACE (3I FACILI'TY NAME III 5 p 0 p 2 5 0 OF Turke Point Unit 3 1

Loss of Flowpath from Boric Acid Storage Tanks to Reactor Coolant System Due to Coupling Failure of the 3B Boric Acid Transfer Pump (BATP) and Seal Failure of the 3A BAT EVENT DATE ISI LER NVMSE'R (6) REPORT DATE (7) OTHER FACILITIES INVOLVED IS)

FACILITY NAMES OOCKFT NVMSERISI MON TN DAY YEAR YEAR SCavENTIAL NUMBER '4i6i: REVISION MONTH NUMBER OAY YEAR Turke Poxnt UnLt 4 0 5 0 0 0 15 88 88 0 0 5 0 0 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT T 0 THE REOUIREMENTS OF 10 CFR (I; (Cn<<fr Onr or move of tnr fonowinPl (11)

OPERATINO MODE (1) 20.402(b) 20.405(cl 60,73( ~ ) (2) (ir) 73.71(5) 1 POWER 20.405 I~ I I I I (i) 60.35(c) (I I 50.73( ~ I (2 I HI 73.71(cl LEVEL 50.73(el(21 (vol DTHER ISpecily in Aorrrrct (10) 20.405( ~ )ill(iil 50.35 (cl (2) oelow end in Tear, Jyf)C Form

'. x- le Y,p<.Q 20.406(r)(ll(iii) 50.73( ~ l(2) lil 50.73( ~ I(2) lviii)(Al 366A) 20A05 (4) I 1)(Iv) 60.73( ~ I(2) (ill 60.73( ~ l(2)(riii)ISI 20.405( ~ l(1 l(v) 50.73( ~ l(2) (iii) 60.73(r)(2)(xl LICENSEE CONTACT FOR THIS LER (12)

NAME TFLEPHONE NUMBER AREA CODE Gabe Salamon, Compliance Engineer 3 05 24 6- 65 60 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

MANVFAC COMPONENT MANUFAC CAUSE SYSTEM COMPONENT SYSTEM TURER TVRER g~>'+~Ox XCACPLG G 0 N SEA

'~z'P~'VPPLEMENTAL X C A L G 0 0 N REPORT EXPECTED (14) MONTH DAY YEAR EXPECTFD SV BM ISS ION DATE I)5)

YES llfyn, complrre EXPECTED S(fEMISStDIY DA TEI NO ABSTRACT lLimit ro 1400 g>>cer, I r., rpproeimr rely fifteen rlnplrrpecr typerwlrren linnl (16)

On April 14, 1988, at 0305, the 3B Boric Acid Transfer Pump (BATP) was taken out of service (OOS) due to the pump s failure to deliver flow.

Technical Specification (TS) 3.6.b.4 requires a flow path from the boric acid storage tanks (BAST) when a reactor is critical.sealOn tank April 15, at 1315, a Nuclear Operator reported that the 3A BATP was showing no water. As both pumps which were aligned to Unit 3 were now OOS, no flow path from the BASTs to Unit 3 for which credit could be taken existed. This placed the unit in TS 3.0.1, which requires that action be initiated within one hour to place the unit in a mode in which TS 3.6.b.4 does not apply (MODE 3). At 1415, the 4A BATP was aligned to Unit 3. The unit exited TS 3.0.1 and entered TS 3.6.d.2, which permits continued power operation with one of the three required BATPs OOS for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. IST of the 3B BATP was completed and the pump was returned to service at 1715 on April 15, at which time the unit exited TS 3.6.d.2. The cause of the 3B BATP s failure BATP s loose was a set seal water screw in the motor/pump coupling. The cause of the 3A level decrease was a failed seal. The 4A BATP was realigned to provide a boric acid flowpath to Unit 3, and the 3B BATP was returned to service at was replaced, and 1715 on April 15. The mechanical seal for the 3A BATP on April 18.

the pump was returned to service at 1600 8805230009 380513 NRC Form 366 (9 63)

PDR ADOCK 05000250 S ncn

C Form 3dda V.S. NVCLEAA AEGULATORY COMMISSION 831 LICENSEE EVE REPORT HLER) TEXT CONTINUATIQ~ APPAOYEooMBNO.3150M(04 EXPI RES I 8/3(I 88 FACILITY NAME 111 OOCKET NUMBEA (ll LEA NUMBER (8) PAGE (3)

SEQUENTIAL i<v% REVISION NUMSEA 4%1 NUMSEA Turkey Point Unit 3 p g p p p 2 5 0 8 8 0 0 5 00 02 OF 0 3 TEXT (II mruo FINoo ro Foouuors uro oddro'oool tvRc Form 3dsa FI (IT(

EVENT On April 14, 1988, at 0305, with both units in MODE 1, the 3B Boric Acid Transfer Pump (BATP) (EIIS:CA) was taken out of service (OOS) due to the pump s failure to deliver'low. Turkey Point has four BATPs: two designated Unit 3 and two designated unit 4, and 3 Boric Acid Storage Tanks (BAST). Any of the pumps or tanks can be aligned to either unit. Technical Specification (TS) 3.6.c.2 requires three BATPs to be operable during dual unit operation. TS 3.6.b.4 requires the establishment of one flow path from the BASTs when a reactor is critical . With the 3B BATP OOS, three pumps remained operable, and entry into a TS action statement was not required . The pump was repaired by 0540 on April 15, however, it was not returned to service at that time as inservice testing (IST) was not yet complete . On April 15, at 1315, on his normal rounds, a Nuclear Operator reported that the 3A BATP seal tank was showing no water and the nitrogen cover gas pressure, which should have been greater than 35 psig, was at 15 psig and decreasing. At the time of this event, the 4A and 4B BATPs were aligned to Unit 4, the 3A BATP was OOS, and though the 3B BATP was capable of delivering flow to Unit 3, it too was technically OOS. As both pumps which were aligned to Unit 3 were OOS, no flow path from the BASTs to Unit 3 for which credit could be taken existed. Failure to have a flow path places the unit in TS 3.0.1, which requires that action be initiated within one hour to place the unit in a mode in which TS 3.6.b.4 does not apply (MODE 3). Preparations to enter mode 2 were initiated. At 1415, the 4A BATP was aligned to Unit 3. The unit exited TS 3.0.1 and entered TS 3.6.d .2, which permits continued power operation with one of the three required BATPs OOS, provided that it is restored to operable status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. IST of the 3B BATP was completed and the pump was returned to service at 1715 on April 15.

With only the 3A BATP now OOS and three BATPs operable, the unit exited TS 3.6.d.2.

CAUSE OF EVENT The cause of the 3B BATP s failure to deliver adequate flow was a loose set screw in the coupling between the pump motor and the pump. The loose set screw permitted the motor to turn without imparting any motive force to the pump. The cause of the set screw becoming loose is not known as no excessive vibration was noted and the pump had been operating satisfactorily.

Th cause of the 3A BATP s seal water level decrease was a failed seal. The seal is cooled by inleakage of water from the seal tank. This water is pressurized by a nitrogen cover.

NRC FORM SddA (9 831

U.S NUCLEAR REGULATORY COMMISSION R Form 366A

)4)3)

LICENSEE EV REPORT {LER) TEXT CONTINUATI APPROVEO OMB NO319)M(04 EXPIRESI 8/31/88 FACILITY NAME (() OOCKET NUMBER (3) LER NUMBER (6) PAGE (3l YEAR SEGUENT/AL REYISIGN P5).) srUMBE/I rr U M B E R Turkey Point Unit 3 o so oo 250 8 8 005 00 030F 0 3 TEXT /i/mOro s/rsoo is ror/vr'rod, vss sddrrr'Orrs/ /YRC Form 3684 4/ ()T)

ANALYSIS OF EVENT.

During this event, both units were in NODE 1. With a unit in HODE 1, an emergency boration path is required . Even though the 3A BATP was OOS and the 3B BATP was technically OOS, the 3B BATP had the coupling set screw tightened and was available for use had emergency boration been required. In fact, no emergency boration was required as no transients or events requiring emergency boration occurred. Additionally, upon discovery of the loss of flowpath, one of the Unit 4 BATPs was quickly aligned to provide a flowpath to Unit 3. Additionally, the flowpath from the Refueling Water Storage Tank to the charging pumps and the safety injection pumps was available. Based on the above, the health and safety of the public were not affected.

CORRECTIVE ACTIONS

1) The 4A BATP was realigned to provide a boric acid flowpath to Unit 3 at 1415 on April 15.

2) IST of the 3B BATP was initiated at 1350 on April 15, completed satisfactorily, and the 3B BATP was returned to service at 1715 on April 15.

3) The mechanical seal for the 3A BATP was replaced, and the pump was returned to service at 1600 on April 18.

ADDITIONAL DETAILS The BATPs are manufactured by Goulds, Ines) model number 3196-ST-8. The mechanical seals are manufactured by Durametallic.

Similar occurrences: a previous BATP seal failure was reported in LER 250-87-17.

IIRC <<ORM 366A (94)3)

NAY 1 3 l9d8 L-88-225 10 CFR 50.73 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555 Gentlemen:

Re: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 Reportable Event: 88-05 Date of Event: April 15, 1988 Loss of Flowpath from Boric Acid Storage Tanks to Reactor Coolant System Due to Coupling Failure qf 3B Boric Acid Transfer Pum BATP and Seal Failure of 3A BATP The attached Licensee Event Report (LER) is being submitted pursuant to the requirements of 10 CFR 50.73 to provide notification of the subject event.

Very truly yours, W. F. nway Senio ice President Nuclear WFC/SDF/gp Attachment cc: Dr. J. Nelson Grace, Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant SDF3. LER an FPL Group company