ML19256F649

Significant Deficiency Rept 369-370/79-06,suppl Re Personnel Air Lock Door Seals.All Penetrating Bolt Holes & Holes Deviating from Perpendicular Re More than 3 Degrees Were Plugged,Drilled & Tapped.Action Completed by 800131

ML19256F649
Person / Time
Site:	Mcguire, McGuire
Issue date:	11/30/1979
From:	Parker W DUKE POWER CO.
To:
Shared Package
ML19256F650	List: ML19256F649 ML19256F651
References
NUDOCS 7912190710
Download: ML19256F649 (2)

Text

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DUKE POWER COMPANY Powra Butmixo 422 SocTa Cauncu STazzT, CEARWTTE, N. C. asa42

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Sitas. Paoowcwoas 373-4053 Mr. J. P. O'Reilly, Director U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, Suite 3100 Atlanta, GA 30303 e

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Re: McGuire Nuclear Station Units 1 and 2 ,-

Docket Nos. 50-369 and 50-370 SD 369-370/79-06, Supplement 1

Dear Mr. O'Reilly:

My letter of August 31, 1979, transmitted Significant Deficiency Report SD 369-370/79-06 which described a problem with the personnel air lock door seals. In the original report we committed to provide further details on the corrective actions taken. This information is contained herein.

A meeting was held at McGuire Nuclear Station on August 20, 1979, between Duke Power Company and W. J. Woolley Company to discuss the deficiencies and corrective actions. Subsequent to this meeting, W. J. Woolley Company developed procedures for shop inspection and repair at Irwin Steel Fabricators in Canton, Ohio (Attachment #1). All of the personnel air lock door seal bolt holes were inspected for penetration depth, thread condition, thread depth, and perpendicularity.

All fully penetrating bolt holes and all bolt holes which deviate from the perpendicular by more than three degrees were plugged, drilled, and tapped as shown on W. J. Woolley drawing 36973 (Attachment #2). Similar drawings of all doors provide a record of repairs and existing bolt hold conditions.

Deficiencies related to thread condition and depth were repaired with threaded inserts. Attachment #3 shows a section of the threaded insert in place.

These high strength inserts are installed after the holes have been re-tapped.

The pullout resistance of the tapped hole is actually increased since the inserts allow greater shear area contact.

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Mr. J. P. O'Reilly, Director November 30, 1979 Page Tuo .

These corrective actions for Unit I will be completed and the personnel air lock door seals reinstalled by January 31, 1980. The schedule for implementing these corrective actions on the Unit 2 personnel air lock door seals will be consistent with the startup activities for Unit 2.

Very ruly yours,

/bu * /j . u William O. Parker, Jr.

THH/sch Attachments cc: Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555 mm 9