ML20023D499

Corrects Ltr Identification Number Submitted for 830504 Final Deficiency Rept Re Rocker Arm Assembly Holddown Screw. SNRC-873 Should Be SNRC-883

ML20023D499
Person / Time
Site:	Shoreham File:Long Island Lighting Company icon.png
Issue date:	05/12/1983
From:	Brandi V LONG ISLAND LIGHTING CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
SNRC-873, NUDOCS 8305200549
Download: ML20023D499 (1)

Text

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l 8 LONG ISLAND LIGHTING COMPANY f) l

, SHOREHAM NUCLEAR POWER STATION

. c - = _w.uw$ P.O. BOX 618, NORTH COUNTRY ROAD + WADING RIVER, N.Y.11792 Direct Dial Number May 12, 1983 All Parties:

Shoreham Nuclear Power Station - Unit 1 W.O. 44430/48923

Dear Sir:

Please note that attached letter (dated May 4, 1983) was sent to you with the incorrect SNRC number (SNRC-8 73) . Please correct your copy. Correct SNRC number is: SNRC-883.

Very truly yours, L,G. l J V. A. Brandi Project Administrator Shoreham Nuclear Power Station mp O

8305200549 830512 PDR ADOCK 05000322 S PDR FC- 8 9 35.1

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i. m.uwe. .+ w t 17 S EAST 01.0 C o u t41 H Y Ft O A D

• H f C KSV a L L E, NEW YORK 88001 I m d N 1 N ur.ocr .-

May 4, 1983 -

SNRC- 883 Ilr. James M. Allan 1seting 11cgional Administrator Office of Inspection t. Enforcement, Region i U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406 Long Island Lighting Company Shoreham Nuclear Power Station - Unit 1 Docket No. 50-322

Dear Mr. Allan:

On March 30, 1983, in accordance with 10CFR50.55 (c) , we reported

, verbally to Region 1 a potential deficiency concerning the failure of a rocker arm assembly holddown capscrew on the Shoreham Emergency Standby Dieccl Generators. This letter scrves as our 30-day written report on this potential deficiency.

Description of the Potential Deficiency

'The three diesel generators which are af fccted were manufactured by the Transar. erica Delaval Company of Oakland, California. These diesel generators, 1R43*G-101, 1R43*G-132, and 1R43*G-103, in the Diesel Emergency Power System are designed to provide standby emergency power for cultiple plant safety related systema.

The problem was discovered during testing of Diesel Generator 103 (lR43*G-lO3) when a sudden change in the sound of the running engine was detected by tac c pe r a t.c r . The open. tor .: hut dow:. the engine and an attenpt was made to determine the source of the noise. Upon removing the valve cover of the sl cylinder, it war discovered that the intermediate-intake rocker arm assembly hold-down capscrew had failed.

Subsequent to the failure, a preliminary field inspection of the

} failed capscrew was performed by a LILCO metallurgy specialist in T [F d y J U ~J lcA(.) D J

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hay 4, 1983 - '

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Transamerica Dclaval. On the basis of the preliminary field in-spection, it appeared that the failure was due to fatigue loading with cracking found to be initiated at the bolt thread root. As a result of the findings of this field inspection, magnetic particle

' inspection was conducted on all rocker arm assembly holddoun cap-screws and linear indications were noted on 46 of them. The failed capscrew and its asrociated rocker arm assembly and sub-cover were then returned in their "as found" condition to Transamerica Delaval for a formal failure analysis, as were the 46 capscrews with linear indications. Although ,the Transamerica De'laval fail-ure analysis report has not yet bean roccived, verbal discussions with Transamerica Delaval have indicated that their examination results to date have not revealed significant indications on the balance of the capscrews which would have been indicative of incipient failures. .

Corrective Action & Action to Prevent Reoccurrence Although Transamerica Delaval has advised, as described above, that the capscrew failure was an isolated instance, LILCO has elected to change out all original capscrews in this application and replace them with a modified Transamerica Delaval, design cap-screw uith improved fatigue characteristics.

'This redesign is based on a rocker s, haft bolt developed for Delaval's HV-A series enginc. The modified rocker shaft bolts are designed to reduce fatigue sensitivity in the bolt by transferring the regions of highest stress away from the stress concentrations in the root of the threads and reducing the cyclic loading on the bolt. The reduction in cyclic loading is achieved by decreasing the diameter of the shank, thereby increasing the elongation / stress relationship of the bolt. This effectively transfers more of the cyclic load to the stiffer rocker arm shaft, which is loaded in compression.

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The rocker arm capscrew changeouts have been completed via E&DCR F-45462, therefore, our corrective cction has been completed. Any further replacements for these capscrews will be of the improved design.

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'If y'ou have any questions relative to this ma'tter, please do not  :

hesitate to contact us.

Very truly yours, 2 Origina.l signrfil by

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J. L. Smith j Manager, Special Projects j

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Shorcham Duclear Power Station WMJ/ laws 3 a

cc: Mr. Richard DcYoung, Director )

HRC Office of Inspection & Enforcement

, Division of Reactor Operating Inspection j Washington, D.C. 20555  :

5 Mr. J. Higgins, Site NRC 1

1 All Parties - Attachment 1 i s

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1. ATTACliMENT 1 t Herbert H. Brown, Esq.

' nawrence Brenner, Esq.

Administrative Judge Lawrence Coe Lanpher, Esq.

Atomic Safety and Licensing Karla J. Letsche, Esq.

Board Panel Kirkpatrick, Lockhart, Hill U.S. Nuclear Regulatory Ccmmission Christopher & Phillips Washington, D.C. 20555 8th Floor 1900 M Street, N.W.

Dr. Peter A. Morria Washington, D.C. 20036 Administrative Judge Ato;uic Safety and Licensing Mr. Marc W. Goldsmith '

Board Panel Energy Research Group U.S. Nuclear Rcgulatory Commission 4001 Totten Pond Road Washingt.on, D.C. 20555 Waltham, Massachusett.n 02154 Dr. James H. Carpenter MHB Technical Associates Administrative Judge 1723 Hamilton Avenue Atomic Safety and Licensing Suite K Board Panel San Jose, California 95125 U.S. Nuclear Regulatory Commission Washington, D.C. 20555

• Stephen B. Latham, Esq.

Twomey, Latham & Shea Daniel F. Brown, Esq 33 West Second Street Attorney P.O. Box 398 -

Atomic Safety and Licensing 'Riverhead, New York 11901 sBoard Panel C' j . S . Nuclear Regulatory Commission Ralph Shapiro, Esq.

Washington, D.C. 20555 Cammer and Shapiro, P.C.

9 East 40th Street Bernard M. Bordenick, Esq. New York, New York ~ 10016 David A. Repha, Esq.

U.S. Nuclear Regulatory Commission Matthew J. Kelly, Esq.

Washington, D.C. 20555 State of New York i Department of Public Service James Dougherty Three Empire State Plaza 30/.5 Porter Street Albany, New York 12223 Washington, D.C. 20008 1

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