05000333/LER-2020-003-01, High Pressure Coolant Injection Inoperable Due to Oil Leak

High Pressure Coolant Injection Inoperable Due to Oil Leak

ML21251A585
Person / Time
Site:	FitzPatrick
Issue date:	09/08/2021
From:	Timothy Peter Exelon Generation Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
JAFP-21-0082 LER 2020-003-01
Download: ML21251A585 (4)

LER-2020-003, High Pressure Coolant Injection Inoperable Due to Oil Leak

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
3332020003R01 - NRC Website

text

Exelon Generation James A. FitzPatrick NPP P 0 Box 110 Lycoming. NY 13093

JAFP-21-0082 Timothy C. Peter Site Vice President-JAF September 8, 2021

United States Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001

James A. FitzPatrick Nuclear Power Plant Renewed Facility Operating License No. DPR-059 NRC Docket No. 50-333

Subject: LER: 2020-003-01, High Pressure Coolant Injection Inoperable due to Oil Leak

Reference: FitzPatrick letter, LER: 2020-003, High Pressure Coolant Injection Inoperable due to Oil Leak, JAFP-20-0042, dated June 9, 2020

Dear Sir or Madam:

This report is supplement 1 to Licensee Event Report (LER) submitted by the Reference. This report is being submitted pursuant to 50.73(a)(2)(v)(D) and 50.73(a)(2)(i)(B). This LER revision is being submitted to include reference to reporting criterion 50.73(a)(2)(i)(B) for Operation or Condition Prohibited by Technical Specifications (TS) and include more information in the Event Analysis section. Subsequent analysis of the event determined the High Pressure Coolant Injection (HPCI) system was inoperable for a longer period than allowed by Technical Specifications 3.5.1.

There are no new regulatory commitments contained in this report.

Questions concerning this report may be addressed to Mr. Richard Sullivan, Regulatory Assurance Manager, at (315) 349-6562.

sincz {L_

£~t Site Vice President

TCP/RS

Enclosure: LER: 2020-003-01, High Pressure Coolant Injection Inoperable due to Oil Leak cc: USNRC, Region I Administrator USNRC, Project Manager USNRC, Resident Inspector INPO Records Center (IRIS)

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2023 (08-2020)

James A. FitzPatrick Nuclear Power Plant 05000333 1 OF 3

4. Title High Pressure Coolant Injection Inoperable due to Oil Leak

5. Event Date 6. LER Number 7. Report Date 8. Other Facilities Involved Revision Facility Name Docket Number Month Day Year Year Sequential Number No. Month Day Year N/A N/A

Facility Name Docket Number 04 10 2020 2020 - 003 - 01   N/A N/A

9. Operating Mode 10. Power Level 1 100 No Yes (If yes, complete 15. Expected Submission date)

Abstract (Limit to 1560 spaces, i.e., approximately 15 single-spaced typewritten lines)

On April 10, 2020 at 0300, an oil leak from 23PCV-12, HPCI Trip System Pressure Control Valve (PCV) resulted in the system being declared inoperable. This conditio n is being reported as a condition that could have prevented the fulfillment of the safety function of a syst em needed to mitigate the consequences of an accident per 10 CFR 50.73(a)(2)(v)(D) and for a period longer t han allowed by Technical Specification 3.5.1 per 10 CFR 50.73(a)(2)(i)(B).

Corrective action to replace valve 23PCV-12 was completed and s ystem was restored to service at time 2015 on April 10, 2020.

NRC FORM 366 (08-2020)

Background

The High Pressure Coolant Injection (HPCI) System [EIIS Identif ier: BJ] is part of the Emergency Core Cooling System (ECCS); HPCI provides and maintains an adequate coolant inventory inside the Reactor Pressure Vessel [RPV] to prevent damage to the reactor core under postul ated accident scenarios. The system is comprised of various components which include a turbine, pumps, valves, piping, and instrumentation. The HPCI System may be initiated by automatic or manual means.

The HPCI turbine oil system provides for lubrication and coolin g of the equipment bearings and other accessories. The oil system also provides control and hydrauli c oil to the turbine governor system. Loss of oil pressure to the turbine governor system will cause the steam su pply stop valve and turbine control valve to go shut, securing steam to the turbine. The HPCI oil system is not normally pressurized, the system is only pressurized during operational checks of the system and during actual system operation.

Event Description

While conducting a HPCI monthly operability test (ST-4B), a con trol oil leak was observed from 23PCV-12.

The oil leak is only visible when the oil system is pressurized. Initial leakage rate was estimated at approximately 0.1 gallons per minute. To confirm leak location and validate leak rate, the auxiliary oil pump was restarted. With system oil pressure reestablished, the leak rate was determined to have degraded such that the capability of the HPCI system to meet mission time wou ld be challenged.

Event Analysis

Level in the HPCI Oil Tank provides net positive suction head ( NPSH) to the suctions of the oil pumps for the duration of HPCI mission time. Loss of NPSH to the suction of H PCI Main Lube Oil Pump (23P-1MO) and the HPCI Turbine Aux. Lube Oil Pump (23P-150) will result in a loss of oil pressure to the system bearings and system control valves. Oil pressure is required for operation o f the HPCI Turbine Steam Supply Stop Valve (23HOV-1) and HPCI Turbine Control Valve (23HOV-2). Loss of bea ring cooling and oil pressure for the stop and control valves would have limited HPCI operation and challe nged the capability of the HPCI system to meet its mission time. 23PCV-12 was installed on December 16, 2 017. It was identified that this PCV had a vulnerability associated with the HPCI system oil PCV actuator diaphragm due to a manufacturing error, as reported by General Electric-Hitachi MFN 10-192. This error res ulted in inadequate fabric reinforcement that is critical to ensure durability and reliability of the diaphragm, preventing tearing of the diaphragm. The failure of 23PCV-12 diaphragm would result in a loss of HPCI system turbin e lubricating and control oil through the failed diaphragm. This condition is reportable under 10 CFR 50. 73(a)(2)(v)(D), Event or Condition that Could Have Prevented Fulfillment of a Safety Function.

Due to the cyclic failure mechanism of the diaphragm, HPCI was inoperable longer than allowed by Technical Specifications (TS) 3.5.1, ECCS Operating. TS 3.5.1 Condition C requires HPCI System be restored to Operable within 14 days or, Condition G, be in Mode 3 and reduc e reactor steam dome pressure to 150 psig within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This represents a condition prohibited by Tech Spec and reportable in accordance with 10 CFR 50.73(a)(2)(i)(B).

Cause

The cause was determined to be a tear in the 23PCV-12 control v alve diaphragm, allowing a loss of control oil from the system. NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2023 (08-2020)

James A. FitzPatrick Nuclear Power Plant 05000 - 333 NUMBER N0.

2020 - 003 - 01

Similar Events

Previous LER: None identified.

FAILED COMPONENT IDENTIFICATION:

Manufacturer: Robertshaw Manufacturer Model Number: VC-210 NPRDS Manufacturer Code: R290 NPRDS Component Code: PCV FitzPatrick Component ID: 23PCV-12

Completed Corrective Actions

Valve 23PCV-12 was replaced. Additional corrective actions are documented in the Corrective Action Program.

Safety Significance

Nuclear Safety - The failure of the HPCI turbine over-speed reset control valve diaphragm would result in a loss of HPCI turbine lubricating oil and control oil during HPI C oil system operation. Depending on the amount of oil lost and system demands, the leakage may have prevented the HPCI from meeting system specified mission time.

Industrial safety - No actual or potential industrial safety consequences result ed from this event.

Radiological safety - No actual radiological impact is associated with this event.

References Issue Report - IR 04334315, HPCI Oil Leak, dated April 10, 202 0 Issue Report - IR 04397491, NRC NCV 05000333/2020012-01, Defec tive Part HPIC PCV Failure, dated January 22, 2021 ENS 54657, issued 4/10/2020 Part 21 Reportable Condition Notification: Failure of HPCI Tur bine Overspeed Reset Control Valve Diaphragm, MFN 10-192, dated July 1, 2010