05000272/LER-2004-001, Regarding as Found Value for Main Steam Safety Value Lift Setpoint Exceeds Technical Specification Allowable Limit

Regarding as Found Value for Main Steam Safety Value Lift Setpoint Exceeds Technical Specification Allowable Limit

ML041670543
Person / Time
Site:	Salem
Issue date:	06/03/2004
From:	Public Service Enterprise Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LR-N04-0235 LER 04-001-00
Download: ML041670543 (5)

LER-2004-001, Regarding as Found Value for Main Steam Safety Value Lift Setpoint Exceeds Technical Specification Allowable Limit

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
2722004001R00 - NRC Website

text

PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, New Jersey 08038-0236 O PSEG ATu clear LLC JUN 0 3 2004 LR - N04 - 0235 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen:

LER 272/04-001-00 SALEM - UNIT 1 FACILITY OPERATING LICENSE NO. DPR-70 DOCKET NO. 50-272 This Licensee Event Report, "As Found Value for Main Steam Safety Valve Lift Setpoint Exceeds Technical Specification Allowable Limit" is being submitted pursuant to the requirements of the Code of Federal Regulations 10 CFR 50.73(a)(2)(i)(B), Operation or Condition Prohibited by technical Specifications.

The attached LER contains no commitments.

Sincere an ager-Salem Attachment

/EHV C

Distribution LER File 3.7 95-2168 REV. 7/99

Abstract

During the Salem Unit 1 sixteenth refueling outage (1 R16), ten of the Main Steam Safety Valves were initially lift setpoint tested in accordance with the Inservice Test (IST) Program. On April 9, 2004, PSEG discovered that one of the Main Steam Safety Valves tested failed its as-found lift setpoint test. The as-found actuation pressure for Main Steam Safety Valve 1 3MS1 3 was below the lower limit of minus 3% of the nameplate setpoint as stated in the Salem Technical Specification (TS) Table 3.7-1. The TS value is 1110 psig +/- 3%.

The apparent cause of this event has been attributed to excessive seat leakage, which caused the valve to lift at a low set pressure. A contributing cause to the event is suspected to be steam cutting of the seating surfaces. Because the actual lift set point of the 13MS13 was not within the required acceptance criterion of

+1-3%, two additional Main Steam Safety Valves were tested. The two additional Main Steam Safety Valves (11 MS1 3 and 11 MS1 4) tested satisfactory and no further testing was required. The failed valve was replaced with a pre-tested and certified spare.

This event is reportable per the requirements of 10 CFR 50.73(a)(2)(i)(B), Operation or Condition Prohibited by technical Specifications.

NFIC FORM 366 (7-2001)

(If more space Is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use addiionalcopies of NRC Form 366A) (17)

SAFETY CONSEQUENCES AND IMPLICATIONS

There was no safety significance to this event.

There are twenty MSSVs installed in Salem Unit 1. These valves are equally distributed in four Main Steam Headers each containing five MSSVs with setpoints varying from a low of 1070 psig to a high of 1125 psig and a tolerance of +/- 3%. The MSSVs provide over pressurization protection for the Steam Generators on the secondary side and the Main Steam System.

During 1 R1 6 a total of twelve MSSVs were tested, including two additional MSSVs as a result of the failure of 13MS13. Eleven valves lifted within the set point tolerances and one valve lifted earlier by a few tenths of one pound. A Main Steam Safety Valve lifting earlier (greater than - 3%) is an operational transient that would result in depressurizing the main steam lines. However, the potential consequences of the inadvertent depressurization caused by the lifting of a safety valve are bounded by the main steam line break analyses.

In this case, the small difference between the allowable setpoint and the as found lift setpoint, just a few tenths of one pound, would have had minimal to no impact on plant safety. The ability of the Main Steam Safety Valve to provide over pressurization protection for the Steam Generators on the secondary side was never compromised.

This event does not constitutes a Safety System Functional Failure (SSFF) as defined in Nuclear Energy Institute (NEI) 99-02, Regulatory Assessment Performance Indicator Guideline.

CORRECTIVE ACTIONS

1. The failed MSSV was replaced with a pre-tested and certified spare.

2. Expanded scope of MSSV testing to include an additional two MSSVs from another header in accordance with the IST Program. The two additional MSSVs tested satisfactorily.

3. The failed MSSV valve was removed and is currently at the offsite test facility and will be disassembled and repaired.

COMMITMENTS

The corrective actions cited in this LER are voluntary enhancements and do not constitute commitments.