ML19210E678

Interim Deficiency Rept Re Cracks & Tears in 4.16 Kv Switchgear Panels.Based on Satisfactory Evaluation of Proposals,Insp & Repair Program Will Be Implemented.Final Rept Will Be Submitted by 800415

ML19210E678
Person / Time
Site:	Perry
Issue date:	11/23/1979
From:	Davidson D CLEVELAND ELECTRIC ILLUMINATING CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
NUDOCS 7912050519
Download: ML19210E678 (2)

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i iUMINATING SLOG. e PUSLIC SQUARE e CLEVELAND. OHIO 24101 e TELEPHONE (216) 623-1350 e MAIL ADDRESS: P. O. BOX 5000 Dalwyn R. Davidson CCE DAESICENT AfSTEM ENG:NEERING AND CCNSTRUOTION November 23, 1979 Mr. James G. Keppler Director, Region III Office of Inspection and Enforcement U.S. Nuclear Regulatory Cer.'ission 799 Roosevelt Road Glen Ellyn, Illinoie 60137 RE: Perry Nuclear Power Plant Interim Report on 4.16 Kv Switchgear

Dear Mr. Keppler:

This letter will serve as an interim report as required by 10CFR50.55(e) on the deficiency concerning ITE 4.16 Kv Switchgear. This item was first discussed in a telephone conversation between Mr. W. J. Kacer of The Cleveland Electric Illuminating Cc=pany, and Mr. Jim Konklin of the NRC Region III, Office of Inspection and Enforcement on October 23, 1(179 .

Description of Deficiency ITE Corporation was centracted by The Cleveland Electric Illuminating Cc=pany to canufacture Class IE 4.16 Kv Switchgear for Ferry Nuclear Pr- - Plant. Field inspection of four units revealed the existance c' cracks and tears at the bottom of the steel enclosures where the

=etal is bent to allov =cunting to embedded channels. Since it is generally felt these cracks and tears cculd travel the entire length of the bend and could adversely affect the safe operation or shutdown of the nuclear power plant, extensive evaluation and repair will be requ' ired to establish the adequacy of the switchgear panels.

Discussion of this problem with ITE representatives revealed that the cracks and tears were caused by low level vibration experienced during shipment of single frame switchgear units. In order to correct this problem ITE has proposed that a hole be drilled ahead of the cracks en the bend line of the sheetmetal to eli=inate further cracking and/or teari:y;, and that a fillet veld be made the length of the crack er tear to provide the necessary strength for seismic mounting.

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L Mr. James G., Keppler Nove=ber 23, ISrt9 It was further pointed out that seismic testing of the single frame unit requires substantial angle iron supports to be installed at each of its four corners in order to survive the seismic environment.

An alternate method of support would be to attach three frames together. Therefct e, to prevent reoccurance of this deficiency, ITE has proposed that a minbmm of three (3) switchgear frames be lotted together and mounted on a single skid for shipment.

At the present time CEI is evaluating the proposed corrective action and steps to prevent reoccurance. In addition, they are evaluating the effect the proposed repair will have on the integrity of the seismic qualification. Based on a satisfactory evaluation of the proposals, an inspection and repair program will be implemented and is expected to be completed by March 1980. A final report will then be submitted by April 15, 1980.

Very truly yours, v4 .m Dalw' R. Davidson Vice President System Engineering and Construction DRD:ge cc: Victor Stello, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Co==ission Washingten, D. C. 20555 1502 245 9 mW