ENS 48834
ENS Event | |
|---|---|
12:38 Mar 20, 2013 | |
| Title | Part 21 - Asco Direct Acting 3-Way Solenoid Valve Failure |
| Event Description | The following is a summary of a Part 21 report received from ASCO Valves Inc., via facsimile:
ASCO received a failed solenoid actuated valve from its distributor (Areva). The valve has been qualified for 1-E nuclear use and is referred to as a NP8320 direct acting 3-way valve. The valve that failed would not shift when de-energized. Information accompanying the valve identified that it was operating for approximately three months since August 2012. The valve was manufactured in May 2010. The valve was disassembled and the spring was observed to be not on the core completely. The valve was re-assembled with the spring properly on the core and subjected to cycling. During cycle testing the second turn of the spring was shown to completely overlap the first turn coming over the edge of the core, pulling the first turn off of the core. The spring came completely off the core in 97 cycles. ASCO identified that the spring was not properly manufactured as the beginning of the second turn was not wound to the same diameter of the first turn. ASCO and the spring supplier identified the manufacturing lot that was the source of the spring for serial number A483456-001. ASCO identified 10 nuclear valves manufactured with this manufacturing lot. The remaining 3990 springs from this lot were used in commercial valves. ASCO uses this same spring in approximately 40,000+ commercial valves per year and no commercial returns have been found with the same condition of this spring coming off the core. Neither ASCO's incoming inspection nor the spring manufacturer detected the nonconformance for this manufacturing lot. ASCO evaluated other valves that used this same spring manufactured from other lots received in 2010. These valves represent a time period shortly before and shortly after the manufacture of the above valve. ASCO's investigation concluded that these springs are conforming. This condition may cause the spring to work itself off the core and present a situation where the valve would not shift to its de-energized position. ASCO believes the condition would present itself relatively early into its cycle life. ASCO has contacted the customer, AREVA, who received the 10 valves in question. ASCO has implemented corrective actions to include inspection of the spring assembled to the core at nuclear dedication inspection to verify that the spring is properly seated and the second turn does not overlap the first at the springs working length. ASCO does not have adequate knowledge of the actual installation and operating conditions of these valves to determine whether their malfunction could create a 'substantial safety hazard' as defined in 10 CFR 21.3. We are providing this information to inform you of our investigation results, corrective action and customer notification. If you have any questions, you can contact Bob Amone at 803-641-9395. |
| Where | |
|---|---|
| Asco Valve Incorporated Aiken, South Carolina (NRC Region 1) | |
| Organization: | Asco Valve Incorporated |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+-1.95 h-0.0813 days <br />-0.0116 weeks <br />-0.00267 months <br />) | |
| Opened: | Bob Amone 10:41 Mar 20, 2013 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Mar 20, 2013 |
| 48834 - NRC Website | |
Asco Valve Incorporated with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 488342013-03-20T12:38:00020 March 2013 12:38:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 - Asco Direct Acting 3-Way Solenoid Valve Failure 2013-03-20T12:38:00 | |