ENS Event | |
|---|---|
16:50 May 11, 2023 | |
| Title | Part 21 - CAP Screw Improper Length |
| Event Description | The following information was provided by the licensee via email:
This is a non-emergency notification required by 10 CFR 21.21(d)(3)(i). A written notification in accordance with 10 CFR 21.21(d)(3)(ii) will be provided within 30 days. Steam generator emergency feedwater header discharge isolation check valves (XVC01009A-EF, XVC01009B-EF, and XVC01009C-EF) were designed specifically for and supplied to VC Summer Nuclear Station (VCSNS) by Flowserve under purchase order 4500653391 to replace the previous valves in the emergency feedwater system during refueling outage 27. On May 11, 2023, after valve installation, but prior to initial service, the socket head cap screws were identified as being shorter than the required design length. Valve drawings indicate a design length of 1.25" while the socket head cap screws received were 0.875". The correct length cap screws were installed prior to initial service. VCSNS completed a substantial safety hazard evaluation and determined that the improper length of the cap screws constituted a substantial safety hazard. This deviation in cap screw length resulted in a partial engagement of the cap screw to the cylinder rod extension and could potentially affect valve operation. The NRC Senior Resident Inspector has been notified. |
| Where | |
|---|---|
Summer  South Carolina (NRC Region 2) | |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+1364.02 h56.834 days <br />8.119 weeks <br />1.868 months <br />) | |
| Opened: | Hank Kirkland 12:51 Jul 7, 2023 |
| NRC Officer: | Sam Colvard |
| Last Updated: | Jul 10, 2023 |
| 56612 - NRC Website
Loading map... | |
Unit 1 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Hot Shutdown (0 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 566122023-05-11T16:50:00011 May 2023 16:50:00
[Table view]10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 - CAP Screw Improper Length ENS 569192021-11-12T05:00:00012 November 2021 05:00:00 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 - EATON-CUTLER Hammer Relay on Emergency Diesel Failed ENS 558082021-06-22T05:00:00022 June 2021 05:00:00 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 - Poppet Seal Failure ENS 569202021-05-05T05:00:0005 May 2021 05:00:00 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect Part 21 - Gould Field Flash Relay on Emergency Diesel Failed 2023-05-11T16:50:00 | |