ML20028C248

First Interim Deficiency Rept Re Insufficient Length of Starting Air Valve Assembly Capscrews.Initially Reported on 821201.Transamerica Delaval,Inc Changed Designed Length of Capscrew.Next Rept by 830415.Also Reportable Per Part 21

ML20028C248
Person / Time
Site:	Bellefonte, 05000000, Hartsville
Issue date:	12/30/1982
From:	Mills L TENNESSEE VALLEY AUTHORITY
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
REF-PT21-83 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8301070255
Download: ML20028C248 (2)

Text

, e . .*e TENNESSEE VALLEY AUTHORITY CH ATTANOOGA. TENNESSEE 374o1 400 Chestnut Street Tower II December 30, 1982 HTRD-50-518/82-24, -520/82-24 BLRD-50-438/82-82, -439/82-73 t, u

U.S. Nuclear Regulatory Commission v Region II Ty.

f, ATTN: James P. O'Reilly, Regional Administrator #

101 Marietta Street, Suite 3100 3 Atlanta, Georgia 30303 p a: .

Dear Mr. O'Reilly:

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HARTSVILLE PLANT A AND BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - REPORTAtthE DEFICIENCY - DELAVAL PROBLEM WITH STARTING AIR VALVE ASSEMBLY ON STANDBY ~

DIESELS - HTRD-50-518/82-24, -520/82 BLRD-50-438/82-82, -439/82-73 The subject deficiency was initially reported to NRC-0IE, Region II, Inspector P. E. Fredrickson on December 1, 1982 in accordance with 10 CFR 50.55(e) as NCR's HTA MEB 8202 and BLN HEB 8207. Enclosed is our first interim report.

We anticipate submitting our next report on or before April 15, 1983 We consider 10 CFR Part 21 to be applicable to this deficiency.

If you have any questions, please call Jim Domer at FTS 858-2725 for llartsville and Ralph Shell at FTS 858-2688 for Bellefonte.

Very truly yours, TENNESSEE VALLEY AUTHORITY L. M." Mills, Manager Nuclear Licensing i

Enclosure cc: Mr. R. C. DeYoung, Director (Enclosure)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission j

Washington, D.C. 20555 l

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ENCLOSURE HARTSVILLE A AND BELLEFONTE UNITS 1 AND 2 NUCLEAR PLANTS DELAVAL PROBLEM WITH STARTING AIR VALVE ASSEMBLY ON STANDBY DIESELS 10CFR50.55(e)

NCRs HTA MEB 8202 AND BLN-MEB 8207 HTRD 50-518/82-24, -520/82-24 BLRD 50-438/82-82, -439/82-73 FIRST INTERIM REPORT Description of Deficiency There exists a potential problem with the starting air valve assemblies for TVA's standby diesel generators at Bellefonte and Hartsville A Nuclear Plants. The standby diesel generators were manufactured by Transamerica Delaval, Inc, (TDI), of Oakland California. The starting air valve assembly was manufactured and installed in the cylinder head by TDI. "fDI h'as notified the NRC of this defect under 10 CFR 21 by letter dated May 13, 1982 from R. E.

Boyer, Manager, Quality Assurance to the Director of the Office of Inspection and Enforcement.

The potential defect is related to the length of the capscrew which holds the starting air valve assembly in the cylinder head. If all .

dimension tolerance is stacked in one direction, the installed clearance is less than desirable. If this capscrew bottoms in the tapped hole in the cylinder head before the assembly is properly seated, the torque wrench reading would be misleading and the assembly would be too loose and could possibly fail.

Interim Progress TDI's engineering group has reviewed the problem and found that a 1/4" shorter capscrew still gives adequate engagement and eliminates any possiblity that the capscrew will bottom in the tapped hole.

TDI has changed the designed length of their capscrew from 3" to 2-3/4" long.

Since it is impossible to determine if this problem exists in an installed assembly, TDI recommends removing the capscrews and cutting off 1/4" and reinstalling or replacing the existing capscrews with a new 2-3/4" long capscrew. TVA is evaluating the TDI recommendation. More information concerning the resolution of this nonconformance will be forwarded in the next report.

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