ENS Event | |
|---|---|
04:00 Jan 18, 2019 | |
| Title | Part 21 Report - Improper Anti-Rotation Key Dimension on Glove Valve |
| Event Description | This notification is being submitted pursuant to the guidelines of 10 CFR Part 21 to report that a 24" Class 150 Globe valve for RHRSW HX Isolation MOV, E1150F068A at Detroit Edison - Fermi 2, failed to fully open due to the failure of the anti-rotation key.
The site notified WVC [Weir Valves and Controls] USA on January 18th of this issue involving a new bonnet that was installed which included a key bushing/key assembly. The new bonnet used was from an originally supplied valve assembly on WVC USA order 0010001147-10 with a quantity of one, Detroit Edison Company PO 4700732583. The key is welded on top and bottom in the key bushing keyway to hold the key in place. After a month in service, during operation, the welds failed which caused the key to drop out or be driven out from the key bushing by friction/vibration. Upon review of the design it was found that the key and key slot were not dimensioned properly for a tight fit allowing a larger than recommended gap between key and keyway. This gap allowed the operational torque loads to put the welds in bending which caused the welds to fail. Loss of the key renders the valve inoperable to open or close. The site has currently restored the key bushing/key assembly with new keys with proper fit and welds to ensure the key is retained. [WVC USA] has performed an extent condition review and has concluded that one other operating site, Georgia Power - SNC, Hatch Unit 1 1WVC USA order 0010000081-10 (55544A), Southern Nuclear Operating Co PO SNG10025571 has a similar key/key bushing assembly. There was a quantity of six valve assemblies shipped for this purchase order. The site has been contacted to evaluate the fit of the key bushing/key assembly. Engineering has determined that improper design clearance was the cause of failure. [WVC USA is] performing corrective actions to ensure future re-occurrences cannot occur in design engineering. Affected sites include: Fermi Unit 2 and Hatch Unit 1. For additional information, contact: Allen Fisher Director of Engineering allen.fisher@mail.weir 978-825-845 |
| Where | |
|---|---|
| Weir Valves & Controls Ipswich, Massachusetts (NRC Region 1) | |
| Organization: | Weir Valves & Controls |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+1260.63 h52.526 days <br />7.504 weeks <br />1.727 months <br />) | |
| Opened: | Allen Fisher 15:38 Mar 11, 2019 |
| NRC Officer: | Caty Nolan |
| Last Updated: | Mar 11, 2019 |
| 53928 - NRC Website | |
Weir Valves & Controls with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 539282019-01-18T04:00:00018 January 2019 04:00:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 Report - Improper Anti-Rotation Key Dimension on Glove Valve 2019-01-18T04:00:00 | |