Part 21 Report - 1997-640

ACCESSION #: 9708070153 SOR 14685 W. 105th Street o Lenexa, Kansas 66215-5964 USA Tel. 913.888.2630 - Fax 913.888.0767 9001 REGISTERED Mr. Anil S. Gautam, NRC Subject: 10CFR21 dated October 14, 1994 Dear Mr. Gautam: In July of 1993 SOR began to manufacture pressure, vacuum, and temperature switches that were qualified by SOR test report 9058-102. In September of 1994 SOR was notified of a manufacturing defect by Nebraska Public Power (Ref. RGA 2125, seven defective units) and Connecticut Yankee (Ref. RGA 2117, one defective unit). In addition SOR assembly personnel had identified the same defect (Ref. MRR 1479, one defective unit). The defect was identified as a crack in the lead wire insulation. This prompted SOR to issue a 10CFR21 and investigate the cause of the defect. The cause of the cracked insulation was a heavy coating of epoxy on the wires outside of the potted area and was due to poor workmanship. This condition went undetected because SOR quality inspectors did not notice the coating of epoxy on the wires. As noted in the Part 21 Notification, the following corrective action was taken in October 1994: 1. The Work Order formats for the conduit seals were revised to include specific instructions not to allow epoxy on the wires. In addition, there is an inspection step at the end of the Work Order that instructs the inspector to examine the wire and reject any that have epoxy on the wire. Each of these steps must be signed off on the Work Order by Manufacturing and QA personnel for each order of conduit seals. 2. Shrink tubing was added to the lead wires where they exit the conduit seal. The purpose of this tubing is to protect the wire insulation during shipping and handling. This step is signed off on the assembly procedure by Manufacturing and it is reviewed by QA personnel for every switch. 3. The wire manufacturers recommended minimum bend radius was added to the SOR General Instructions that are provided to the customer with each switch. The conduit seals are manufactured as a sub-assembly in a separate environmentally controlled room. Therefore, there is no danger of epoxy contamination on any other parts of the switches. Reference Corrective Action Report 0357. Regards, Colbert Turnev, V. P. Quality Joseph G. Modig, Engineer *** END OF DOCUMENT ***

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