ENS 57654
ENS Event | |
|---|---|
04:00 Apr 7, 2025 | |
| Title | Part 21 - General Electric Time Delay Relay Failure |
| Event Description | The following is a summary of the information provided by the licensee via email:
This is a report made in accordance with 10 CFR Part 21.21 on a failure of a Curtiss Wright (CW) supplied General Electric (GE) time delay relay. On 12/10/24, Constellation notified CW about the failure of the relay. Constellation stated the relay failed a planned maintenance test. The induction disc was unable to complete the full travel towards the under-voltage trip due to obstruction from the stationary contact, which slipped down along the shaft upon which it was mounted, and made contact with the induction disc. On 2/13/25, CW received the failed CW supplied GE time delay relay from Constellation. Further research discovered that LaSalle had a similar failure in 2002, but there have not been any other reported failures in the nuclear industry until this one. On 4/07/25, Revision 2 of the failure analysis written by Constellation Power Labs stated similar results as those of 12/10/24. The bracket, even when fully tightened, could not hold its position on the shaft. The root cause of the failure could not be determined. Because CW cannot establish a root cause, the following checks are recommended: 1) CW has modified the dedication plan to apply mild vertical force to assure that the clamp is secure as part of the dedication process. 2) End users should provide a similar mechanical test to be sure that the clamp remains secure during periodic surveillance and maintenance activities. These actions should preclude a possible recurrence of this failure mechanism. Relay information: Part number: 12IAV69A1A Manufacturer's serial number: AIAV111700032 CW tag number: CJ678001 CW serial number: 03 Affected facilities: Unknown Responsible Curtis-Wright representative: Mark Papke QA Manager Curtiss-Wright 4600 East Tech Drive, Cincinnati, OH 45245
Curtiss Wright (CW) provided a copy of the undervoltage relay failure analysis Revision 2 written by Constellation Power Labs to the Nuclear Regulatory Commission. The report included conclusions, observations, and a test plan. In addition, CW sent out a test procedure to the customer. CW has indicated that customers should perform a routine maintenance check on the contact/clamp. Affected facilities: Constellation Fleet Notified R1DO (Schussler), R2DO (Franke), R3DO (Hills), R4DO (Vossmar), and Part 21 group (Email). |
| Where | |
|---|---|
| Curtiss Wright Flow Control Co. Cincinnati, Ohio (NRC Region 3) | |
| Organization: | Curtiss Wright Flow Control Co. |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+35.75 h1.49 days <br />0.213 weeks <br />0.049 months <br />) | |
| Opened: | Mark Papke 15:45 Apr 8, 2025 |
| NRC Officer: | Robert A. Thompson |
| Last Updated: | Apr 9, 2025 |
| 57654 - NRC Website | |
Curtiss Wright Flow Control Co. with 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
WEEKMONTHYEARENS 576542025-04-07T04:00:0007 April 2025 04:00:00
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