ML20137G444

Relief Request BV2-B1.11-1,Rev 0 to Reactor Vessel Lower Circumferential Weld (2RCS-Rev21-C-4)

ML20137G444
Person / Time
Site:	Beaver Valley
Issue date:	03/12/1997
From:	DUQUESNE LIGHT CO.
To:
Shared Package
ML20137G377	List: ML20137G371 ML20137G408 ML20137G422 ML20137G435 ML20137G444 ML20137G455 ML20137G459 ML20137G465 ML20137G479
References
PROC-970312-03, PROC-970312-3, NUDOCS 9704010397
Download: ML20137G444 (2)

Text

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2TYPP-1 INSERVICE INSPECTION PLAN FOR THE FIRST TEN-YEAR INTERVAL l AT BEAVER VALLEY POWER STATION UNIT #2 RELIEF REQUEST BV2-Bl.11-1, REY. 0 1

SUBJECT:

Reactor Vessel Lower Circumferential Weld (2RCS-REV21-C-4) 1 1

I Prepared by: MM b DPNA3 Date: t /DOl47 Supenisor', Inspection and Standards l

1 Reviewed by: b _ d. A 84M Date: 3-ll-93 Director, Nuclear Analysis and Inpon j i

i Reviewed by: 3 - 05C., - (e- 4 'I Date: &l 8 A[47' OSC Meeting No. l Reviewed by: btkAA 4 $I' l Date: J/d4 /f 7 ORC Meeting No.

Approval by: m r, ea Date: 3-/2~ )

DI'V. VP, Nuclear Obrations / Plant hhnager i

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9704010397 9?O325 f PDR ADOCK 05000334!

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. I DUQUESNE LIGHT COMPANY Beaver Valley Power Station Unit No. 2 RELIEF REOUEST NO. BV2-Bl .11-1. Rev. O COMPONENT Reactor Vessel Lower Head Circumferential Weld (2RCS-REV21-C-4)

DRAWING NO.

10080-ISI-E-1 A ASME SECTION XI REOUIREMENT (83S83)

Item No. Bl.11 (IWB-2500-1, Category B-A) requires volumetric examination of essentially 100% of the weld length each 10 year interval. Further,10CFR50.55a(g)(6)(ii)(A) requires that examination requirements for reactor vessel shell welds specified in item Bl.10 of Examination Category B-A in Table IWB-2500-1 of subsection IWB of the 1989 Edition of Section XI be implemented as part of the current inspection interval.

BASIS OF RELIEF In accordance with 10CFR50.55a(g)(6)(i), reliefis requested on the basis that compliance with the Code requirement is impractical. The lower head to shell weld (2RCS-REV21-C-4) examination is limited due to the four core support lugs.

This weld was examined using automated techniques during the 2R06 refueling outage. Over eighty-nine percent (89%) of the required volume was examined. The four lugs are welded to the inside surface of the reactor vesseljust above weld 2RCS-REV21-C-4.

10CFR50.55a(g)(6)(ii)(A) defines " essentially 100%", for the purposes of the augmented examination, as more than 90 percent of the examination volume of each weld, where the reduction in coverage is due to interference by another component, or part geometry. To obtain the last 1% of the required volume would necessitate removal of one of the support lugs. Removal of a support lug for this purpose is considered impractical.

ALTERNATIVE EXAMINATION The alternative to the examination requirement is to perform the examination to the maximum extent possible. This examination is supplemented by the visual examination performed on the interior of the vessel. The four support lugs are included in this examination. Therefore, the UT examination coupled with the visual examination of the support lugs and the surrounding areas provides an adequate measure of assurance of the integrity of this weld.

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