Friday, January 17, 2020

Hope Creek's SRVs Still Continously Fail Testing

JAN O 6 2020 

Hope Creek Licensee Event Report 2019-002-00, Safety Relief Valve (SRV) As-found Set-point Failure

ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) On November 08, 2019, Hope Creek Generating Station (HCGS) received results that the second 'as-found' set-point test for safety relief valve (SRV) pilot stage assemblies had exceeded the lift setting tolerance prescribed in Technical Specification (TS) 3.4.2.1. The TS requires the SRV lift settings to be within +/- 3% of the nominal set-point value. 
During the twenty-second refueling outage (H1 R22), all fourteen SRV pilot stage assemblies were tested at an offsite facility. Between October 22 and November 25, 2019, HCGS received the test results for all fourteen of the SRV pilot valve assemblies. A total of six of the fourteen SRV pilot stage assemblies were outside of the TS 3.4.2.1 specified values. All of the valves failing to meet the limits were Target Rock Model 7567F two-stage SRVs. 
Exceeding the set points for five of the six SRV pilot stage assemblies is attributed to corrosion bonding between the pilot discs and seating surfaces, which is consistent with industry experience. The cause of exceeding the sixth SRV set-point was pilot failure or spindle/disc contact wear.
Fitz (Both New LERs)
 The As-Found test results for the eleven Safety/Relief Valve (S/RV) pilot assemblies removed and replaced during the 2018 Refueling Outage at James A. FitzPatrick Nuclear Power Plant (JAF) identified eight (8) S/RV pilot assemblies that lifted outside of the allowable tolerance required by Technical Specification Surveillance Requirement 3.4.3.1. Eight (8) two-stage S/RV’s were found out of tolerance high.  The eight S/RV pilot assemblies are assumed to have been inoperable at some point in the operating cycle that preceded the 2017 Refueling Outage resulting in a condition reportable pursuant to 10 CFR 50.73(a)(2)(i)(B). 

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