ML20072R013

Responds to NRC Re Violations Noted in IE Insp Rept 50-358/81-13.Addl Corrective Actions:Based on Review of Large Sample of Socket Welds,Craftsmen Did Follow Project Const Procedure for Socket Weld Fit Up

ML20072R013
Person / Time
Site:	Zimmer
Issue date:	03/08/1983
From:	Borgmann E CINCINNATI GAS & ELECTRIC CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20072R000	List: ML20072R013
References
QA-2290, NUDOCS 8304050411
Download: ML20072R013 (3)

Text

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THE CINCINNATI GAS & ELECTRIC COMPANY ss-CINCINN ATI, OHIO 45201 March 8, 1983 QA-2290 E. A. BoRGM AN N vict passiocwt U.S. Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, Ill. 60137 Attn: Mr. J. G. Keppler Regional Adminstrator Re: WM. H. ZIMMER NUCLEAR POWER STATION - UNIT 1 INSPECTION REPORT 81-13 SOCKET WELDS W.O. 57300, JOB E-5590, FILE #81-13 I Gentlemen:

Appendix A, Item 3C, pages 6 & 7 to NRC Inspection Report 81-13, item of noncompliance 81-13-05 indentifies that licensee records were unable to verify socket disengagement (fit up) in accordance with ASME Code,Section III 1971, Article NB-3661.5(b). This condition was reported to exist for some 439 welds.

We have investigated this situation and feel it can be closed based upon the following:

1. Project construction procedures required craf tsmen to provide dis-engagement during fit up.

2. Quality Confirmation Program (QCP) Task 4 has conducted a review of a very large sample of socket welds. Based upon that review we believe j sufficient confidence exists that craf tsmen did follow the project construction procedure for fit up of socket welds. 25841 socket weld records were reviewed. Only 714 (less than 3%) did not have a Q.C.

Inspector verification of fit up documented. These 714 were further investigated by radiographic and visual examination. In 117 cases verification of disengagement prior to welding could not be demon-strated.

It should be pointed out that the 117 welds where fit up was not verified do not necessarily imply the craftsmen did not follow construction procedures. It simply means disengagement was not documented at the time of fit up and was not verifiable after welding.

Even if proper disengagement was not verified for 117 socket welds, we have demonstrated the site construction procedures were adhered to in greater than 99% of the cases.

These results are based on a review of greater than 70% of the total estimated number of socket welds at the Zimmer Site.

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a Mr. J. G. Keppler-Regional Administrator

' Region III March 8, 1983 Page 2

3. A similar question regarding socket weld fit up was raised on another nuclear plant. Analyses performed by consultants for the utility involved demonstrate that failures will not occur even if socket welds are made without disengagement. The NRC accepted these reports on that docket. A copy of the NRC acceptance letter is attached.

4. The ASME Code is currently acting on changes to NB 4000 (Fabrication and Installation Requirements) which would delete all statements about a gap prior to welding. These actions by the Code would be in accordance with recent analyses of socket welds referenced above.

(Section III January Committee Meeting agenda number 83-113). We anticipate these changes will be incorporated into the Code via the Summer of 1983 Addenda.

Based on the above we believe this matter has been satisfactorily resolved. We trust this will meet with your concurrence and we do not believe that further reviews related to socket veld disengagement are required.

Very truly yours, THE CINCINNATI GAS & ELECTRIC CO.

BY E. A. Borgmann Senior Vice President PMI/jb Attachments cc: NRC Office of Inspection & Enforcement Washington, D.C. 20555 NRC Senior Resident Inspector Attn: W. F. Christianson NRC Zimmer Project Inspector Region III