ML20206D628

Forwards Engineering Analysis Svc & Maint North Anna Power Station Fairbanks-Morse 38 TD8-1/8 Diesel Engines Phase II, Per 860714 Commitment.Addl Info on Status of Investigation Will Be Provided by 870417

ML20206D628
Person / Time
Site:	North Anna
Issue date:	03/31/1987
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20206D632	List: ML20206D628 ML20206D672
References
86-179C, NUDOCS 8704130387
Download: ML20206D628 (2)

Text

o VIHOINIA ELECTHIC AND POWEH COMPANY Ricnwoxn, VIRGINIA 23261 W.L. STEWART Vers Pazmannwr Nuci.si. or= =Ano== March 31, 1987 United States Nuclear Regulatory Commission Serial No. 86-179C Attention: Document Control Desk N0/ ALM:jmj :

Washington, D.C. 20555 Docket Nos. 50-338 50-339 License Nos. NPF-4 NPF-7 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 EMERGENCY DIESEL GENERATOR ENGINEERING EVALUATION Virginia Electric and Power Company has completed Phase II of the North Anna Emergency Diesel Generator (EDG) Engineering Analysis. In our letter dated l July 14, 1986, Serial No. 86-179B, we provided our initial evaluation, which described the root cause of past engine failures and corrective measures that would be implemented. In that letter we committed to provide a detailed engineering report as Phase II of this evaluation. Trident Engineering conducted the analysis and provided the attached report, which has been reviewed by Colt, the engine manufacturer.

This Phase II analysis addresses engine component loads, metallurgical examination of failed bushings, lubrication and control systems evaluation, as well as predictive analysis programs and reliability monitoring. Trident has made a number of recommendations as a result of their evaluation. A number of these recommendations have been or will be implemented at North Anna. The remainder will be evaluated and implemented if appropriate.

I On March 30, 1987 we became aware of a problem involving extrusion of the piston pin floating bushings for two of the upper pistons of the 1H emergency l diesel generator. The problem was identified through our periodic inspection of the gap between the piston pin floating and insert bushings. We are l

currently investigating this problem with the engine manufacturer and our diesel consultant and will provide you additional information on tiie status of l our investigation by April 17, 1987.

If you require additional information or have any questions, please contact us.

Very truly yours, W. L. r Attachment 0 8704130387 870331 s PDR ADOCK 05000338 P PDR L

e cc: U. S. Nuclear Regulatory Commission 101 Marietta Street, N.W.

Suite 2900 Atlanta, CA 30323 Mr. J. L. Caldwell NRC Senior Resident Inspector North Anna Power Station L

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