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On May 2-3, 2002, with the unit at approxi … On May 2-3, 2002, with the unit at approximately 52% power, seven of twenty Main Steam Safety Valves (MSSVs) (EIIS:SB,RV) failed to meet Technical Specifications (TS) required lift settings specified in TS 4.7.1.1, Table 4.7-1.</br></br>TS 4.7.1.1 allows a +/- 3% tolerance on the as-found lift setting and requires all tested valves to be set to a +/- 1% as-left tolerance. Operations personnel entered the applicable TS Action Statement until each valve was adjusted and tested satisfactorily. In accordance with 10 CFR 50.73(a)(2)(i)(B), this condition is being reported as a condition prohibited by TS.</br></br>The cause of the test failures was attributed to metallic bonding between the valve disc and the nozzle.</br></br>Adjustments were made and all of the "as-left" lift settings were within the +/- 1% acceptable range. No component was left outside of its acceptable range.</br></br>The MSSVs ensure that the secondary system pressure will be limited to within 110% of 1085 psig during the most severe anticipated system operational transient. The as-found test results of the seven valves discussed in this LER were still well below the 110% design pressure value. Thus, there is reasonable assurance that the valves were capable of performing their primary safety function as well as maintaining an adequate heat sink for the primary side. Therefore, this event is not considered safety significant since the valves in question would have performed their function.stion would have performed their function. +
May 3, 2002 +
On May 2-3, 2002, with the unit at approxi … On May 2-3, 2002, with the unit at approximately 52% power, seven of twenty Main Steam Safety Valves (MSSVs) (EIIS:SB,RV) failed to meet Technical Specifications (TS) required lift settings specified in TS 4.7.1.1, Table 4.7-1.</br></br>TS 4.7.1.1 allows a +/- 3% tolerance on the as-found lift setting and requires all tested valves to be set to a +/- 1% as-left tolerance. Operations personnel entered the applicable TS Action Statement until each valve was adjusted and tested satisfactorily. In accordance with 10 CFR 50.73(a)(2)(i)(B), this condition is being reported as a condition prohibited by TS.</br></br>The cause of the test failures was attributed to metallic bonding between the valve disc and the nozzle.</br></br>Adjustments were made and all of the "as-left" lift settings were within the +/- 1% acceptable range. No component was left outside of its acceptable range.</br></br>The MSSVs ensure that the secondary system pressure will be limited to within 110% of 1085 psig during the most severe anticipated system operational transient. The as-found test results of the seven valves discussed in this LER were still well below the 110% design pressure value. Thus, there is reasonable assurance that the valves were capable of performing their primary safety function as well as maintaining an adequate heat sink for the primary side. Therefore, this event is not considered safety significant since the valves in question would have performed their function.stion would have performed their function. +
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05:26:28, 1 December 2017 +
June 28, 2002 +
May 3, 2002 +
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