ML19338C789

Deficiency Rept Re Cracking Problem in Electrical Wiring Conduit.Caused by Overbending Below Original Published Min Inside Bend Diameters.Will Replace Conduits Installed at Bend Diameters Below Min Inside Bend Diameter

ML19338C789
Person / Time
Site:	Waterford
Issue date:	08/29/1980
From:	Cady W, Knight K ANACONDA CO. (DIV. OF ATLANTIC RICHFIELD CO.)
To:
Shared Package
ML19338C791	List: ML19338C789 ML19338C795 ML19338C796
References
NUDOCS 8009050288
Download: ML19338C789 (2)

Text

THIS DOCUMENT CONTAINS ANACONTA Metal Hose-P0OR QUAUTY PAGESg 6f/- NsV P.O. Box 2618 Waterbury, Conn. C6723 Telephone: 2'J3 5748500 AN ACONCA 'navstr.e s Auguse 29, 1980 Director, Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Dear Su:

On Friday, August 22, 1980, we were notified by Ebasco Services / Louisiana Power and Light Company (Waterford #3) that they were filing a report with the NRC under 10CFR50.55(e) because of a cover cracking problem in our electrical wiring conduit marketed under the trade name of Nuclear Wiring Conduit Type NWC.

We first learned of the potect ial cover cracking problem on June 17, 1980.

On July 8,1980, our Mr. W. S. Cady, Supervisor, Applications Engineering, arid Mr. M. D. York, District Sales Manager, visited Waterford #3 to examine instal-lation of the hTC which exhibited cover cracking.

During this visit, several installations were inspected and inside. bend diameters (IBD) measwements were taken in order to compare actuals to those minimum IBD's listed in our Technical Data Report 3727, Revision 5/11/79, copy attached (Exhibit A).

At this time, it became evident thct in all cases of cover cracking, the instal-lation was below the minimum IBD in our Technical Data Report 3727, Revision 5/11/79.

Refer to attached photographs of actual installation configuration and showing cover cracking (Exhibit B).

Coincidentally, the May 11, 1979 revision of our Technical Data Report 3727 was made for the purpose of increasing the minimum IBD's due to an error in our engi-neering derivation involving the transition from electrical cable bend diameters to that of hvC wiring conduit bed diameters. This reexamination was prompted by cases where cover cracking resulted from overbending below our original published minimum inside bend diameters and, therefore, not viewed as a serious matter. Ebasco and other customers were advised of appropriate corrective actka to ensure that. the hVC conduit would be installed to the revised bend diameters.

It is Ebasco's position that we have failed to meet the requirements of their purchase order #WP3-1564 and Tc eairni Specification LOU 1564.249B with regard to IBD capabilities of our hTC an! NFw nuclear wiring conduit. This is a result of Ebasco's reference to UL 360 Specification (Exhibit C) which specifies IBD's well below our product capabilities. During our July S visit, it was determined that many IBD's were e tually below that of UL 360. Refer to Table I showing measured IBD's of several installations with comparison to our Technical Data Report 3727, Revision 5/11/79 and UL 360 (Exhibit G).

At the time of the inquiry and contract, we did not take exception to the referenced UL 360 Specification since we interpreted this to apply to the core material (metallic stripwounc" product under outer cover) only and so state this in our Technical Data Report 3727 as well as our final product certification (Exhibit D).

The Waterford #3 job was quoted referencing our Technical Data Report 3727 and a copy of this document was in eneir possession.

y S

go 00050 2 8 8 con inued....

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t Director, August 29, 1980 Office of Inspection and Enforcement We are concerned about the potential for cover cracking in our NWC product at other facilities if it is bent below the minimum IBD's in our Technical Data Report 3727.

Cover cracking could possibly result in ingress of moisture which could possibly result in electrical fault. A list of purchasers of our Type NWC wiring conduit is included (Exhibit E).

As a corrective action, we have advised Ebasco Services that our minimum IBD's must be strictly adhered to and. hat, as a sales policy, we agreed to replace all conduit installed at bend diameters below our minimum IBD. Secondly, we are preparing special installation precautions pointing out the importance of adhering to our minimum IBD's during installation which will be forwarded to all present and future users of nuclear wiring conduit (Exhibit F).

This information will also be included within product shipping containers.

Our purpose in reporting the above incident is an effort to fully comply with all notification requirements of the NRC and to take whatever additional actions are recommended. This matter was discussed with Mr. Bill Crossman, Section Chief, NRC Region IV, on August 27, 1980.

Should you require additional information, please feel free to contact us.

Sincerely yours, k). M.

W. S. Cady Supervisor Applications Engineering

.[e-$ IQM J K. F. Knight Quality Control Manager WSC/KFK/cs cc:

Mr. Karl Seyfrit Nuclear Regulatory Commission, Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, TX 76012 Attachments:

Exhibit A - Technical Data Report 3727 Exhibit B - Photographs Exhibit C - UL 360 Exhibit D - Product Certification Exhibit E - List of Purchasers of Type NWC Exhibit F - Installation Precautions Exhibit G - Table I

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