05000400/LER-2021-004, Pressurizer Safety Valve Lift Setpoint Drifted Outside of Technical Specification Tolerance
| ML21172A009 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 06/21/2021 |
| From: | Dills J Duke Energy Progress |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RA-21-0161 LER 2021-004-00 | |
| Download: ML21172A009 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| 4002021004R00 - NRC Website | |
text
John R. Dills Plant Manager Shearon Harris Nuclear Power Plant 5413 Shearon Harris Road New Hill, NC 27562-9300 10 CFR 50.73 June , 2021 Serial: RA-21-0161 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Shearon Harris Nuclear Power Plant, Unit 1 Docket No. 50-400/Renewed License No. NPF-63 Subject: Licensee Event Report 2021-004-00 Ladies and Gentlemen:
Duke Energy Progress, LLC, submits the enclosed Licensee Event Report 2021-004-00 in accordance with 10 CFR 50.73 for Shearon Harris Nuclear Power Plant, Unit 1 (HNP). This report describes a condition where surveillance testing identified a safety valve setting outside of technical specification allowed tolerance. This event had no significance with respect to the health and safety of the public.
There are no regulatory commitments contained within this report.
Please refer any questions regarding this submittal to Sarah McDaniel at (984) 229-2002.
Sincerely, John R. Dills Enclosure: Licensee Event Report 2021-004-00 cc:
J. Zeiler, NRC Senior Resident Inspector, HNP M. Mahoney, NRC Project Manager, HNP NRC Regional Administrator, Region II
Abstract
Shearon Harris Nuclear Power Plant, Unit 1 400 3
Pressurizer Safety Valve Lift Setpoint Drifted Outside of Technical Specification Tolerance 4
29 2021 2021 004 00 6
2021 6
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Sarah McDaniel, Regulatory Affairs Engineer (984) 229-2002 A
AB RV C710 N
On April 29, 2021, while Shearon Harris Nuclear Power Plant, Unit 1 (HNP), was in Mode 6 for a refueling outage, surveillance testing identified that the lift setting of pressurizer safety valve (PSV) 1RC-123 was -1.3 percent (%) from its setpoint, which is outside the Technical Specification (TS) allowed tolerance of +/-1%. The cause of the PSV lift setting being out of tolerance is a personnel error that resulted in inadvertent installation of a valve that had previously demonstrated setpoint drift incompatible with TS criteria. The PSV was replaced with another PSV confirmed to have a lift setting within the TS allowed tolerance and no history of significant drift. The PSV with a history of significant setpoint drift will be retired from service.
The +/-1% TS tolerance is more restrictive than the American Society of Mechanical Engineers code allowed tolerance of +/-3%.
In addition, the safety analysis for the PSVs assumes a PSV tolerance of +/- 3%, so the as-found PSV lift setting of -1.3% is well within the safety analysis. Therefore, this event had no significance with respect to the health and safety of the public. Page of 05000-
- 3. LER NUMBER YEAR SEQUENTIAL NUMBER REV NO.
E. Safety Analysis
Premature operation of the PSV could adversely impact departure from nucleate boiling ratio conditions in events such as the reactor coolant pump [P] seized rotor. The safety analysis for the PSVs assumes a PSV tolerance of +/- 3%, so the as-found PSV lift setting of -1.3% is well within the safety analysis. Therefore, the reported low opening pressure of 1RC-123 had no significance with respect to the health and safety of the public.
F. Additional Information
HNP Licensee Event Report (LER) 2015-001-00 reported a similar condition, where a PSV lift setting was found outside of the TS tolerance.
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Shearon Harris Nuclear Power Plant, Unit 1 400 2021 004 00