The following notification was received via fax:
On 9/18/10 a single solenoid valve was returned to ASCO with a reported problem of external leakage at the bonnet area below the coil housing. The valve was returned from Cooper Nuclear Station through AREVA, who was the distributor.
The returned valve was retested at ASCO. No external leakage was observed when the valve was tested in the de-energized state. However, when the valve was tested in the energized state, the reported leakage was confirmed. The root cause of the leakage was determined to be a misaligned O-ring between the solenoid base sub-assembly and the valve body.
The customers that were shipped affected valves are being notified of the potential non-conformance. ASCO will recommend the affected valves be returned to be retested in accordance with updated test procedures.
- * * UPDATE FROM ROBERT ARNONE TO JOE O'HARA VIA FAX AT 1308 ON 11/11/10 * * *
In our continuing investigation of the external leakage in NP8320 solenoid valves (Ref A), ASCO has identified an additional group of valves which could be potentially susceptible to such leakage. The initial review focused on our standard NP8320 products and did not include our special construction valves. However, we expanded our review to include all special as well as standard NP8320 valves. As a result, the quantity of potentially affected valves has increased from 174 to 438. In response to this new information, revised notices were sent to the original customers and the newly identified customers: ASCO Canada, SPX Industries, and Flowserve.
As of this date, 115 valves have been returned. None of these returned valves has exhibited external leakage when retested per the updated procedure.
Through their expanded review process, ASCO did not identify any additional commercial nuclear power plant customers which had purchased valves susceptible to the leakage issue.
Notified R4DO (Gaddy) and Part 21 Group via e-mail.