ML20011A830

Deficiency Rept Re Poor Quality Rung Weld in Cable Tray Tee Sections Mfg by Tj Cope,Initially Reported on 810331.Specs Will Be Revised to Require Visual Insp of Each Weld Prior to Galvanization by 811130

ML20011A830
Person / Time
Site:	Millstone
Issue date:	10/19/1981
From:	Counsil W NORTHEAST NUCLEAR ENERGY CO.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
10CFR-050.55E, 10CFR-50.55E, AEC-MP3-252, B10214, NUDOCS 8111030261
Download: ML20011A830 (3)

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October 19, 1981 Docket No. 50-423 AEC-MP3-252 B10214 Mr. Ronald C. Haynes Region 1 Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

Reference:

(1) N. G. Counsil letter to B. H. Grier, dated April 29, 1981.

Gentler n:

Millstone Nuclear Power Station, Unit No. 3 Reporting of Potential Significant Deficiencies in Design and Construction As required by Title 10, Code of Federal Regulations Part 50, Paragraph ES(+ ) , Northeast Nuclear Energy Company (NNECO) reported a potential s Maificant deficiency in the construction of Millstone Unit No.3 in the above-referenced letter. At that time, details on the method of repair and corrective actions were not specified. Therefore, this letter is being written as a follow-up to provide you with this information.

In Reference (1) we stated that poor quality rung welds in cable tray tee sectionc manufactured by T. J. Cope could result in a po-tential significant deficiency during a seismic event and as a result a Stop Work Order was issued to prevent installation of all rerwining safety-related cable tray tees.

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. Subsequently, a meeting was held with the vendor to discuss the problem.

The meeting established that there were non-conformances to the vendor drawings and some non-generic deficiencies such as broken channels,

' holes in side rails, missed welds, and short channels.

Cable tray tees with non-generic deficiencies were rejected outright.

The bulk of the disposition effort involved the resolution of non-conformances to vendor drawings. It was determined that vendor drawings.did not reflect some current fabrication practices and did not contain sufficient information to facilitate proper weld inspection.

Appropriate drawing change information was provided to Stone and Webster by the vendor. All cable tray tees were reinspected utilizing this advance drawing change information. A total 35 of the 102 tees have been finally rejected (for drawing non-conformance and non-generic deficiency reasons) and 5._.. La returned to the vendor for repair or replacement, or scrappeC. No additional tees will be released for shipment to the site until completion of the preventive action. The sequence of formal preventive action requires that the vendor drawings be formally revised; and, then, that these revisions plus additional inspection requirements be incorporated in the Stone and Webster specification.

To correct drawing deficiencies and to preclude any possible recurrence of the reported potential significant deficiency, the following actions will be taken:

1. Stone and Webster will revise the specifications to require the shop inspector to visually inspect each weld prior to galvanization on 100 percent of the tees, rather than using a sampling technique.

In this manner, an accurate assessment of the conformance of the welds to the specified criteria can be made. Specification re-visions are expected to be complete by November 30, 1981.

2. The vendor will revise detail drawings to reflect present fabrica-tir,n procedures and to incorporate welding dimensions against which the shop inspector can inspect. Revised drawings are to be submitted for approval and record. The shop inspector will verify that tees conform to the approved drawings. Drawing revisions are expected to be complete by November 30, 1981. A Stop Work Order on tees will remain in effect until approved drawings have been ca.npleted.

We trust this report provides you with sufficient detail describing our disposition of the subject potential significant deficiency in construction.

Very truly yours, NORTHEAST NUCLEAR ENEFOY COI4PhW r AWLA W.'G. Counsil Senior " ice President cc: See Following Page

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a cca Mr. Harold D. Thornburg, Director Division of Reactor Construction. Inspection Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. J. C. Mattia Resident NRC Inspector Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission P. O. Box 128 Waterford,.CT 06385

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