ML18004B819

LER 87-029-00:on 870428,snubber Discovered Damaged on Steam Generator Blowdown Sys Piping.Caused by Water Hammer Occurring When Isolation Valve for Line from Containment Opened.Open Stroke Time of Valve Increased.W/Undated Ltr

ML18004B819
Person / Time
Site:	Harris
Issue date:	05/28/1987
From:	Tibbitts D, Watson R CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
HO-870446-(O), LER-87-029, LER-87-29, NUDOCS 8706010367
Download: ML18004B819 (5)

Text

REGS .T INFORNATION DISTRIB BTEN (RIDS)

ACCESSION NBR: 8706010367 DOC. DATE: 87/05/28 NOTARIZED: NO DOCKET

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FAC I L: 50-400 Sh earon Hav.v'i s Nuc 1 eav Power Plant> Uni t ii Car o l ina 05000400 AUTH. NANE AUTHOR AFFILIATION TIBBITl'8, D. L. Cav olina Powev 8c Light Co.

MATSON> R. A. Carolina Powev Zc Li gh+ Co.

REC IP. NANE REC IP I ENT AFFILIATION i

SUBJECT:

LER 87-029-00: on 870428'nubber d iscovev ed damaged on s+eam genev'atov blowdone sos piping. Caused bci water when isolation valve fov'ine from containmen+

hammev'ccuv'v'ing opened. lncv eased open stroke +ime of valve. M/undated l+r.

DISTRIBUTION CODE: IE22D COPIES RFCEIVED: LTR ENCL SIZE:

TITLE: 50. 73 Licensee Event Report (LF'R)i Incident Rpti etc.

NOTES: App lication fov permit v enewal f i led. 05000400 REC IP IENT COP I EB RECIPIENT COP IEB ID CODE/NANE LTTR EiiCL ID CODE/N*i'1E LTTR ENC L PD2-1 LA 1 1 PD2-1 PD 1 1 BUCKLEY, B 1 1 INTERNAL: ACR S NI CHEL SON 1 ACRB NOELLER 2 2 AEOD/DOA 1 1 AEOD/DSP/ROAB 2 2 AEOD/DSP/TPAB DFDRO 1 1 NRR/DEBT/ADE 0 i!RR/DEBT/ADB 1 0 NRA/DEBT/CED 1 NRR/DEBT/ELB 1 1 NRR/DEBT/ I CSB 1 NRR/DEBT/NEB 1 NRR/DEBT/!NTB 1 NRR/DEBT/PSB 1 NRR/DEBT/RBR hRR/DEBT/SGB 1 1 NRR/DLPG/HFB 1 NRR/DLPG/GAB 1 NRR/DOEA/EAB 1 h!RR/DREP/RAB 1 1 NRR/DREP/RPB 2 2 h! R R /P NAS/ I LRB 1 1 NRR/PNAS/PTBD 1 R 02 1 1 REB DEPY Ql 1 F ILE Oi 1 EXTERNAL: E..G8cQ QROH> 1'1 5 5 H ST LOBB Y MARD 1 1 1,PDR 1 NRC PDR 1 NBI C HARB IS, J NBIC NAYS, G 1 1 TOTAL NUl'1BER OF COPIES REQUIRED: LTTR 42 ENCL 40

NRC Form 366 U.S. NUCLEAR REGULATORY COMMISSION (64)3) APPROVED OMB NO. 31500104 EXPIRES: 6/3I/56 LICENSEE EVENT REPORT (LER)

DOCKET NUMBER (2) PA E 3 FACILITY NAME (1)

Shearon Harris Unit 1 0 5 0 0 04 PP1OFP3 TITLE (4)

Steam Generator Blowdown Piping Snubber Inoperable EVENT DATE (5) LER NUMBER LS) REPORT DATE (7) OTHER FACILITIES INVOLVED (6)

': SEQUENTIAL <<M5 REVISION DAY YEAR FACILITYNAMES DOCKET NUMBERISI MONTH DAY YEAR YEAR NUMBER ?4r,'VMSER MONTH 0 5 0 0 0 0 4 28 878 7 029 0 0 052 8 8 7 0 5 0 0 0 THIS REPORT IS SUBMITTED PURSUANT T 0 THE REOUIREMENTS OF 10 cFR (): (Cored onr or mori ol thr Iolloylnpi (11)

OPERATING MODE (6) 20.402(bl 20.405(cl 50,73(al(2)(lv) 73.71(b)

POWER 20.405(a)(1) (II 50.36 (c) (I) 50,73(a l(2)(vl 73.71(c)

LEYEL 1 p p 20.405( ~ ) (1)(6) 50.36(cl(2l 50.734) (2)(vQ) OTHER (Speclry In Abrtrrct trrrow rnd ln Trar, HRC Form 20A05( ~ l(1) (IIII 50.73(a) (2) (0 50.73(a) (2 l(rill)(A) 366A) 20.405 (a) (I ) (lvI 50.73(a l(2)(i(I 50.73(al(2) (rllll(B)

<<...%4WSA., 4.r.....<<h~ 20.405(a) (I) (v) 50.73(a) (2)(ill) 50.73(a) (2)(al LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHONE NUMBER AREA CODE Dean L. Tibbitts Director Re ula o o COMPLETE ONE LINE FOR EACH COMPONENT FAILURE OESCRIBEO IN THIS REPORT (13) v '5,<<'C '

MANUFAC rX'EPORTABLE 5 'AUSE SYSTEM MANUFAC. EPORTABLE ~(

CAUSE SYSTEM COMPONENT TURER TO NPRDS,, <<<<,: ~ COMPONENT TURER TO NPRDS r.. '?

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Irrrnrr..<<: .rr. r. RMm

(%MS SUPPLEMENTAL REPORT EXPECTFD 114) MONTH

$A r <<<<<< lr<<<<?

DAY YEAR EXPECTED SU B MlSS ION DATE I'IS)

YES IIIyrr, conrpletr EXPECTED SUBMISSION DA TEI NO ABSTRACT (Limit to 1400 rpecrr, Ir.. rpproalmrrely llfreen alnprreprcr typevrrltrrn lineal (16)

On April 22, 1987, with the plant in Mode 1 at 100K power level a snubber was discovered damaged on a steam generator blowdown system pipe in the Reactor Auxiliary Building. Action was initiated to repair the snubber, and Technical Specification 3.7.8, SNUBBERS, was reviewed for required actions. A decision was made by shift operations personnel and subsequently confirmed by plant management that Specification 3.7.8 was not applicable to this snubber based on the non-safety significance of the attached system and the location of the snubber and the respective piping relative to safety related equipment.

Upon further review, it was determined on April 28 that the snubber in question was covered by Specification 3.7.8 and that action under this specification was required. The snubber was replaced on April 28 and an engineering evaluation was conducted to verify that the out of service snubber did not result in unacceptable damage to the piping.

870b0103b 7 8705>>

PDR AOOC~ 05000000 pDR 8

NRC Form 366 IB 63)

NRC Poem 388A U$ . NUCLEAR REGULATORY COMMISSlON

(()4)3)'

LICE EE ENT REPORT {LER) TEXT CON U ON APPROVED OMB NO. 3) 50&)84 EXPIRES: 8/31/88 FACILITYNAME ('1) OOCKET NUMBER (2) LER NUMBER (8) PAGE (3)

YEAR SEQUENTIAL ~)o REVISION NUMSER II'2 NUMSER Shearon Harris Unit 1 o s o o o 4p p87 OF TEXT IS ssso <<>>co /4 oe/V/RN/ voo SIEISNN/ NRC Form 38843/ (17)

DESCRIPTION On April 22, 1987, while the plant was operating in Mode 1 "at 100X power level a snubber was found damaged on the Steam Generator Blowdown System piping from Steam Generator lA. The snubber was located inside the Reactor Auxiliary Building. A work request was initiated to repair the snubber. The on-shift operations personnel reviewed Technical Specification 3.7.8, SNUBBERS, and determined that this specification was not applicable because the attached system had no safety function, and was not covered by Technical Specifications.

Work was begun on April 23 to correct the situation. In addition to the damaged snubber, two broken pipe supports and apparent pipe displacement were discovered. The supports were replaced in the evening of April 23. The snubber could not be replaced due to inadequate clearances resulting from the pipe displacement.

On April 27, engineers from the In-Service Inspection group, who had become involved in the repair, informed the Manager Operations that the snubber did require action under Technical Specification 3.7.8, based on their understanding of the specification and its bases. Operations and Regulatory Compliance reviewed the situation and determined that Specification 3.7.8 did not apply based on the non-safety significance of the attached system, on the location of the affected piping relative to safety-related systems, and on the location of the affected piping relative to the containment isolation valve for that particular blowdown line.

The Quality Assurance department became aware of the situation and issued a Non-Conformance Report on April 28. This led to a more detailed review by Regulatory Compliance of the particular snubber and the Technical Specification bases for Specification 3.7.8.', as well as the design bases for the steam generator blowdown system. It was determined that Specification 3.7.8 did in fact apply to the snubber and therefore the plant had not met the requirements of the Technical Specifications to restore the snubber within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and to evaluate the effect on the attached system, or declare the affected system inoperable. However, since the Steam Generator Blowdown System is not covered by a specific specification, declaration of inoperability would require no specific action be taken.

The snubber was replaced on April 28. An engineering evaluation concluded that the "as-left" condition of the piping was acceptable; this was completed on May 7, 1987.

During the time period in question, steam generator blowdown was in service.

The plant was in the applicable modes for which Specification 3.7.8 applies throughout the period. However, during an unrelated outage from May 2 to May 9, the plant entered Mode 4 and steam generator blowdown was secured.

NRC FORM SSSA *U.B.GPO:(988.0.824 538/455 (a83)

NRC Form SBBA US. NUCLEAR REGULATORY COMMISSION (94)3r LICE E NT REPORT (LER) TEXT CON U N APPROVED OMS NO. 3150-0104 EXPIRES: 8/31/88 FACILITYNAME (11 DOCKET NUMBER (2) LER NUMBER (6) PAGE (3) r/E YEAR me, SSGUSNTIAL ~C:r'4 REVISION NUMBBR  ;,~Yr'NUMBBR Shearon Harris Unit TEXT ///rrrrrro 4/rBCB )r nqabaf, rrFB 1 0 5 0 0 0 PO 08 0 2 9 0 0 OF

/1/orro/NRC Fcrrrr 3////AS J (17)

CAUSE The design of the Steam Generator Blowdown piping is safety-related because of FSAR commitments made to support the analysis for high energy piping breaks outside the reactor containment building. Having a Seismic Category I design limits the number of postulated pip'ing breaks to consider as well as relaxing the requirements for pipe whip restraints. Due to the safety-related design of the pipe and the consequences of blowdown line ruptures in the Reactor Auxiliary Building, snubbers in the Steam Generator Blowdown System are subject to Specification 3.7.8. This information is not stated in the Technical Specification nor in the bases section, nor is'it clear based on the action statement of the specification.

Personnel and managers involved in the assessment of the snubber were also not aware of its significance to pipe break analyses. Because a Technical Specification Limiting Condition for Operation was not entered, immediate management attention was not given to the situation and the snubber repair did not proceed within the time allowed by the specification.

The cause of the blowdown piping displacement and snubber damage was determined to be water hammer occurring when the isolation valve for the line from containment is opened.

ANALYSIS This event is being reported per 10CFR50.73 (a) (2) (i) (B) as a violation of the Technical Specifications. The plant design depends on the integrity of steam generator blowdown piping to satisfy high energy line break analyses requirements. Technical Specifications limit the allowed time during which the condition of the piping can be indeterminate prior to requiring action to be taken. This time limit, 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, was exceeded.

There were no safety consequences as a result of this event since the blowdown piping was not damaged to the point where leakage occurred.

CORRECTIVE ACTION The probability of water hammer in the steam gene'rator blowdown piping will be reduced by increasing the open stroke time of the isolation valve. This change will be completed by 07/31/87.

The requirements for action under Specification 3.7.8 have been addressed in a Technical Specification Interpretation document.

NRC FORM 3BBA *U.S.GPO.1988 0.624 538/455 (94)3)

~I",I Carolina Power & Light Company HARRIS NUCLEAR PROJECT P.O. Box 165 New Hill, NC 27562 File Number'SHF/10-13510C Letter Number'. HO-870446 (0)

U.S. Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400 LICENSE NO. NPF-63 LICENSEE EVENT REPORT 87-029-00 Gentlemen'.

In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report fulfills the requirement for a written report within thirty (30) days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September, 1983.

Very truly yours, R. A. Watson Vice President Harris Nuclear Project RAW:sdg Enclosure cc: Dr. J. Nelson Grace (NRC RII)

Mr. G. Maxwell (NRC SHNPP)

MEM/HO-8704460/PAGE 1/Osl