The following was received via facsimile:
This is to notify the Nuclear Regulatory Commission, in accordance of the provisions of 10 CFR Part 21 of a potential deviation identified by Nutherm International, Inc.
On June 26, 2012 one M470 Spring Return Kraus and Naimer (K&N) switch (part number CA10 USN892 - 600 FT1 S0C G211 S0 M470/D1A) failed at the Nutherm facility.
The failed switch was returned to the manufacturer for failure analysis. On July 2, 2012 the manufacturer notified Nutherm that the specific failure mechanism was spring failure on the 'spring return.' The failure was traced to a spring manufacturer supplying the manufacturing facility between November 1, 2011 and June 29, 2012.
Based on this information, M470 spring return switches manufactured during this time period have the potential for this spring failure.
Nutherm has determined that the following site has received these switches from Nutherm and is affected: Farley Nuclear Plant.
- * * UPDATE ON 7/16/13 AT 1221 EDT FROM ADRIENNE SMITH TO DONG PARK * * *
The following was received via facsimile:
This written final report is in response to Event/Accession Number ML121910334 reported by Nutherm International, Inc. There were a total of three (3) switches shipped to Southern Nuclear Operating Company, Farley Nuclear Plant affected by this issue. Southern Nuclear Operating Company, Farley Nuclear Plant was notified on July 2, 2012 of this issue and provided with the specific traceability numbers of all units. None of the units had been installed at the time of the notification.
Southern Nuclear Operating Company returned all three units on July 5, 2012. The units were subsequently destroyed by Nutherm International, Inc.
Corrective actions have been put in place to prevent recurrence of this issue. Corrective actions include additional testing of spring return switches of this model type.
Notified R2DO (Nease) and Part 21 group via email.