ML20083C633

Interim Deficiency Rept Re Discovery of Crack in Piston Skirts Taken from Each Emergency Standby Diesel Generator. Initially Reported on 831101.All Piston Skirts Replaced. Failure Analysis Assoc Rept Encl

ML20083C633
Person / Time
Site:	Shoreham File:Long Island Lighting Company icon.png
Issue date:	12/09/1983
From:	James Smith LONG ISLAND LIGHTING CO.
To:	Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20083C637	List: ML20083C633 ML20083C668
References
10CFR-050.55E, 10CFR-50.55E, SNRC-989, NUDOCS 8312230218
Download: ML20083C633 (3)

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! LONG ISLAND LIGHTING COMPANY l FLCO1 g SHOREHAM NUCLEAR POWER STATION e, .--, J P.O. BOX 610, NORTH COUNTRY ROAD e WADING RIVER, N.Y.11792 D'mnt Dial Number December 9, 1983 SNRC-989 Dr. Thomas E. Murley Regional Administrator Office of Inspection & Enforcement - Region 1 U.S. Nuclear Regulatory Commission 631 Park Avenue King of Drussia, PA 19406 Long Island Lighting Company Shoreham Nuclear Power Station - Unit 1 Docket No. 50-322

Dear Mr. Murley:

On November 1, in accordance with 10CFR50.55 (e) , we reported verbally to Region 1 a potential deficiency concerning the discovery of cracks in piston skirts taken from each of the Shoreham Emergency Standby Diesel Generators. This letter serves as an interim status report of the analyses and correc-tive actions conducted to date.

Description of the Deficiency As part of the ongoing investigation being conducted by LILCO on the Emergency Diesel Generators, a liquid penetrant examina-tion was performed on the inside of the piston skirt of the #7 piston of Diesel Generator 103 (lR43*ENG103). This piston had been removed from service during DG 103 disassembly and inspec-tion. In the course of performing the inspection, linear indica-tions were discovered in the stud attachment boss region where the piston crown is attached to the piston skirt. The piston was then sent to the laboratories of Failure Analysis Associates (FaAA) for further examination. Through destructive examination, it was determined that a fatigue crack was present.

Subsequent liquid penetrant examinations of all pistons from Diesel Generators 101 (lR4 3 *ENG101) , 102 and 103 revealed the presence of linear indications in the same vicinity as those found on the #7 piston from Diesel Generator 103. In all, 23 pistons were found to have one or more indications.

G312230218 831209 PDR ADOCK 05000322 S

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PDR FC 8935.1 l)

December 9, 1983 SNRC-989 Page 2 Corrective Action and Action to Prevent Recurrence In order to conduct additional evaluations, two additional pistons which were determined to have indications were forwarded to FaAA for a more extensive examination. Those pistons also evidenced fatigue cracks, which are described in FaAA's preliminary metallur-gical report (attached).

1 l At present, LILCO has replaced all of the piston skirts in all engines with a different and more recent TDI piston skirt design.

This design, designated "AE" by TDI, has an increased amount of material in the region of the skirt / crown bolting as well as a revised geometry which will improve the load distribution. In addition, FaAA is conducting finite element modeling of the old (modified "AF") and new ("AE") skirt / crown designs to quantify the expected improvement in the operating stress levels in the skirt / crown attachment boss region. A report addreccing this issue, as well as the final results of the metallurgical examina-tions, is expected to be completed by mid-December and will be forwarded to your attention accordingly.

If you have any questions relative to this matter, please do not hesitate to contact us.

Very truly yours,

. L. Smith Manager, Special Projects Shoreham Nuclear Power Station WMJ:mp Attachment cc: Mr. Richard DeYoung, Director NRC Office of Inspection & Enforcement Division of Reactor Operating Inspection Washington, DC 20555 Mr. R. Caruso, NRC NRR Mr. C. Petrone, Site NRC All Parties Listed in Attachment 1 I

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ATTACHMENT 1 f

Lawrence Brenner, Esq. Herbert H. Brown, Esq. l I

Administrative Judge Ldwrence Coe Lanpher, Esq.

Atomic Safety and Licensing Karla J. Letsche, Esq.

Board Panel Kirkpatrick, Lockhart, Hill U.S. Nuclear Regulatory Christopher & Phillips Commission 8th Floor l

. Washington, D.C. 20555 1900 M. Street, N.W. l Washington, D.C. 20036

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Dr. Peter A. Morris l Administrative Judge Mr. Marc W. Goldsmith Atomic Safety and Licensing Energy Research Group Board Panel 4001 Totten Pond Road U.S. Nuclear Regulatory Waltham, Massachusetts 02154 Commission Washington, D.C. 20555 MHB Technical Associates l 1723 Hamilton Avenuc Dr. George A. Ferguson Suite K School of Engineering San Jose, California 95125 Howard University i 2300 6th Street, N.W.

Washington, D.C. 20059 Stephen B. Latham, Esq.

Twomey, Latham & Shea 33 West Second Street Bernard M. Bordenick, Esq. P.O. Box 398 David A. Repka, Esq. Riverhead, New York 11901 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Ralph Shapiro, Esq.

Cammer and Shapiro, P.C.

9 East 40th Street Mr. James Dougharty New York, New York 10016 3045 Porter Street Washington, D.C. 20008 Matthew J. Kelly, Esq.

State of New York Department of Public Service Three Empire State Plaza Albany, New York 12223

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