05000333/LER-2022-003, Safety Relief Valves Lift Setpoint Found Out of Tolerance Low

Safety Relief Valves Lift Setpoint Found Out of Tolerance Low

ML22334A225
Person / Time
Site:	FitzPatrick
Issue date:	11/30/2022
From:	Timothy Peter Constellation Energy Generation
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
JAFP-22-0051 LER 2022-003-00
Download: ML22334A225 (1)

LER-2022-003, Safety Relief Valves Lift Setpoint Found Out of Tolerance Low

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function
3332022003R00 - NRC Website

text

Constellation JAFP-22-0051 November 30, 2022 United States Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001 James A. FitzPatrick NPP P.O Box 110 Lycoming, NY 13093 Timothy C. Peter Site Vice President-JAF James A. FitzPatrick Nuclear Power Plant Renewed Facility Operating License No. DPR-059 NRC Docket No. 50-333 Subject:

Dear Sir or Madam:

LER: 2022-003-00, Safety Relief Valves Lift Setpoint Found Out of Tolerance Low This report is being submitted pursuant to 10 CFR 50. 73(a)(2)(v)(D).

There are no new regulatory commitments contained in this report.

Questions concerning this report may be addressed to Mr. Mark Hawes, Regulatory Assurance Manager (Acting), at (315) 349-6659.

Tim Site TCP/mh Enclosure:

LER: 2022-003-00, Safety Relief Valves Lift Setpoint Found Out of Tolerance Low cc:

USNRC, Region I Administrator USNRC, Project Manager USNRC, Resident Inspector INPO Records Center (IRIS)

NRC FORM 366 (08-2020)

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (08-2020)

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2023

1. Facility Name James A. FitzPatrick Nuclear Power Plant

2. Docket Number 05000333

3. Page 1 OF 4

4. Title Safety Relief Valves Lift Setpoint Found Out of Tolerance Low

5. Event Date

6. LER Number

7. Report Date

8. Other Facilities Involved

Month

Day

Year

Year Sequential Number Revision No.

Month Day Year Facility Name N/A Docket Number N/A 10 01 2022 2022 - 003 - 00 11 30 2022 Facility Name N/A Docket Number N/A

9. Operating Mode 5

10. Power Level 000 Month Day Year No Yes (If yes, complete 15. Expected Submission date) 04 28 2023 Abstract (Limit to 1560 spaces, i.e., approximately 15 single-spaced typewritten lines)

The As-Found test results for eleven Safety/Relief Valve (S/RV) pilot assemblies during the 2022 Refueling Outage at James A. FitzPatrick Nuclear Power Plant (JAF) identified five (5) S/RV pilot assemblies that lifted outside of the allowable tolerance required by Technical Specifications (TS) Surveillance Requirement 3.4.3.1.

Five (5) three-stage S/RVs were found out of tolerance low. Therefore, the TS inoperability of the five (5)

S/RVs resulted in a reportable condition pursuant to 10 CFR 50.73(a)(2)(v)(D).

This condition did not affect the S/RV safety function to relieve vessel overpressure in accordance with the transient analysis. A low lift setpoint reduces the margin for inadvertent SRV actuation.

The failed S/RV were replaced during the outage. An investigation into the cause of this condition is ongoing and a supplement report will be submitted.

(See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/r3/)

(See Page 3 for required number of digits/characters for each block)

LICENSEE EVENT REPORT (LER)

=

Background===

The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code requires the reactor pressure vessel be protected from overpressure during upset conditions by self-actuated safety valves. As part of the nuclear pressure relief system, the size and number of Safety/Relief Valves (S/RV) are selected such that peak pressure in the Reactor Coolant Pressure Boundary (RCPB) will not exceed the ASME Code limits.

The James A. FitzPatrick Nuclear Power Plant (JAF) used eleven (11) three-stage Target Rock S/RV [EIIS Identifier: SB] for emergency pressure relief during operating Cycle 25. These valves are located on the main steam lines between the reactor vessel and the first isolation valve within the drywell. Each S/RV discharges steam through a discharge line to a point below the minimum water level in the suppression pool.

The S/RVs can actuate by either of two modes: the safety mode or the relief mode. In safety mode (or spring mode of operation), the spring-loaded pilot valve opens when steam pressure at the valve inlet overcomes the spring force holding the pilot valve closed. Opening the pilot valve allows a pressure differential to develop across the main valve piston and opens the main valve. This satisfies the code requirement. The Technical Specification (TS) Surveillance Requirement (SR) 3.4.3.1 requires verification that the safety function lift setpoint of the required S/RVs is 1,145 +/- 34.3 psig. Following testing, lift settings shall be within +/- 1%.

The purpose of the lower setpoint tolerance is to ensure sufficient margin exists between the normal operating pressure of the system and the point at which the S/RVs actuate in the safety mode. The nominal operating pressure of the reactor pressure vessel (RPV), at power, is 1,040 psig. For the low tolerance as-found setpoint of -3 percent, the S/RV would lift at 1,110.7 psig and provide an operating margin of 70.7 pounds per square inch differential (psid) between the nominal reactor operating pressure and the lowest margin lift pressure.

This provides sufficient margin to prevent unwanted actuation of the S/RVs postulated to occur during pressurization transients.

Event Description During the JAF Refuel Outage 25, at 0 percent power in Plant Mode 5, work scope removed 6 S/RVs for replacement from locations B, D, F, G, H, and L and were shipped to testing vendor NWS Technologies for as-found testing.

On September 29, 2022, the test found that B S/RV failed its as-found pressure setpoint. Two additional valves C and J were selected as the expanded testing scope; these two S/RVs were removed and shipped to NWS for testing. On October 1, 2022, the G and D failed as-found testing which resulted in all 11 S/RVs needing to be tested. On October 2, 2022, J failed as-found testing and on October 9, 2022, the A failed.

Five of the eleven three-stage S/RV pilots failed low. As-found failed test results are tabulated below: U.S. NUCLEAR REGULATORY COMMISSION (08-2020)

LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2023

3. LER NUMBER James A. FitzPatrick Nuclear Power Plant 05000 - 333 YEAR SEQUENTIAL NUMBER REV N0.

2022

- 003

- 00 Page 3 of 4 (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/r3/)

Table 1 - As-Found Test Results In-service Location Pilot Serial Number First Test (psig)

Acceptance Range (1110.7 - 1179.3 psig) 02RV-71A 119 1109 Unsat - Low 02RV-71B 90 1094 Unsat - Low 02RV-71D 97 1105 Unsat - Low 02RV-71G 27 1100 Unsat - Low 02RV-71J 21 1099 Unsat - Low Event Analysis The TS inoperability of the five (5) S/RVs is a reportable condition in per 10 CFR 50.73(a)(2)(v)(D). The cause of this condition has not been determined at this time. Disassembly and failure analysis will be performed at NWS Technologies in support of this evaluation. A supplemental report will be submitted by April 28, 2023.

Similar Events A series of LER events ending with LER-2019-003 dated September 20, 2019 (JAFP-19-0091), documents a corrosion bonding issue with 2-stage model S/RV. It resulted in increased setpoint drift during as-found testing. This condition is not applicable to this event due to the 2-stage model no longer being installed.

LER-2017-004-01 dated March 30, 2018 (JAFP-18-0033), reported corrosion bonding on 2-stage S/RV and the as-found results included one 3-stage S/RV (02RV-71C) testing low out of tolerance. The cause of the 3-stage S/RV was that its original calibration was in the lower half of the acceptance range.

FAILED COMPONENT IDENTIFICATION:

Manufacturer:

Target Rock Manufacturer Model Number:

0867F-001 Manufacturer Code:

T020 Component Code:

RV FitzPatrick Component ID:

02RV-71A, 02RV-71B, 02RV-71D, 02RV-71G, 02RV-71J Corrective Actions Completed Actions Replaced all 11 S/RV locations prior to refuel outage startup with refurbished and certified components.

Planned Actions The 5 failed S/RV were sent to NWS Technologies for further investigation. U.S. NUCLEAR REGULATORY COMMISSION (08-2020)

LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2023

3. LER NUMBER James A. FitzPatrick Nuclear Power Plant 05000 - 333 YEAR SEQUENTIAL NUMBER REV N0.

2022

- 003

- 00 Page 4 of 4 (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/r3/)

Safety Significance Nuclear safety - There were no actual consequences caused by this condition. This condition does not affect the ASME overpressure transient analysis. The potential consequence of a low out-of-tolerance SRV setpoint is inadvertent S/RV lifting during normal operating pressure or early lifting during postulated accident scenarios. The lowest as-found test B of 1094 psig has 54 psig margin to the nominal operating pressure.

References Issue Reports:

IR 04525986, B SRV test result exceeded TS limit, dated September 30, 2022 IR 04526277, D SRV test result exceeded TS limit, dated October 2, 2022 IR 04526278, G SRV test result exceeded TS limit, dated October 2, 2022 IR 04526428, J SRV test result exceeded TS limit, dated October 3, 2022 IR 04528295, A SRV as found test outside TS limit, dated October 10, 2022 IR 04527149, Safety Relief Valve As-Found Testing Failure Roll-up, dated October 5, 2022