IR 05000269/1985040

Insp Repts 50-269/85-40,50-270/85-40 & 50-287/85-40 on 851209-13.No Violation or Deviation Identified.Major Areas Inspected:Maint & Surveillance Testing of Main Steam Safety Relief & Pressurizer Code Safety Relief Valves

ML20140C740
Person / Time
Site:	Oconee
Issue date:	01/13/1986
From:	Jape F, Schnebli G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20140C736	List: IR 05000269/1985040 ML20140C732
References
50-269-85-40, 50-270-85-40, 50-287-85-40, NUDOCS 8601280396
Download: ML20140C740 (6)

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UNITED STATES .

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NUCLEAR REGULATORY COMMISSION

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j 101 MARIETTA STREET, ,

c ATLANTA, GEORGI A 30323

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Report Nos.: 50-269/85-40, 50-270/85-40, and 50-287/85-40 Licensee: Duke Power Company 422 South Church Street Charlotte, NC 28242 Docket Nos.: 50-269, 50-270, and 50-287 License Nos.: DPR-38, DPR-47, and DPR-55 Facility Name: Oconee 1, 2, rnd 3 Inspection Conducted: December 9-13, 1985

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Inspector: G. Schnebli M/5/86 Date Signed Approved by: , 46444 EA EOS F. Jape, Section Chief (/ / Uate Signed Engineering Branch Division of Reactor Safety SUMMARY Scope: This routine, unannounced inspection entailed 30 inspector-hours on site in the areas of maintenance and surveillance testing of the main steam safety relief (MSRV) valves and the pressurizer code safety relief valve Results: No violations or deviations were identifie /

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8601280396 860116 PDR ADOCK 05000269 G PDR y

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REPORT DETAILS

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. Persons Contacted l

Licensee Employees R. Bond, Compliance Engineer

• T. Matthews, Technical Specialist

*M. Tuckman, Station' Manager R. Van Surdam, Associate Engineer

j Other licensee employees contacted included engineers, technicians, i

mechanics, security force members, and office personne NRC Resident Inspectors j'

J. Bryant, Senior Resident Inspector l L. King, Resident Inspector K. Sasser, Resident Inspector

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• Attended exit interview Exit Interview The inspection scope and findings were summarized on December 13, 1985, with

! those persons indicated in paragraph I above. The inspector described the

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areas inspected and discussed in detail the inspection findings. No dis-senting comments were received from the licensee. The following new items were identified: Inspector Followup Item, 269/85-40-01, Followup on licensee actions to resolve the MSRV blowdown problem (see paragraph 6.a).

i Unresolved Item, 269/85-40-02, Determine reportability of the pressu-

, rizer code safety valves lifting outside of their setpoint tolerance

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during testing (see paragraph 6.b).

The licensee did not identify as proprietary any of the material provided to

or-reviewed by the inspector during this inspection.

L Licensee Action on Previous Enforcement Matters This subject was not addressed in the inspectio . Unresolved Items Unresolved items are matters about which more information is required to determine whether they are acceptable or may involve violations or devia-tions. One new unresolved item identified during this inspection is discussed in paragraph s

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. Independent Inspection Effort

' Construction Progress The inspector conducted a general inspection of the new radioactive waste processing facility at the site to observe construction progress and con-struction activities such as testing, welding, housekeeping and storin Within the areas examined, no violations or deviation were identified. Maintenance and Surveillance Testing of MSRV and Pressurizer Code Safety Relief Valves (61701). , Review of the MSRV Progra In the inspection of the MSRV program, the inspector reviewed the following documents in detail:

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Final Safety Analysis Report (FSAR), Section 10 and Technical Specifications Section 3.4.2 and Table 4.1- Crosby Valve and Gage Company Test Procedure, T-1652, Determining Safety Valve Set Pressure with Air Set Pressure Devic Crosby Valve and Gage Company Instructions for Hydrostatic Testing of Safety Valve Crosby Valve and Gage Company Instructions for the Operation and Maintenance of Crosby Safety Valve Duke Power Company Procedure, MP/0/A/1200/15, Valve; Main Steam, Safety Relief, Reconditionin Duke Power Company Procedure, MP/0/A/1200/89, Valve - Main Steam Safety - Setpoint Tes American Society of Mechanical Engineers (ASME), Section XI, IWV-3500, Inservice Test, Category C Valve ASME, Performance Test Codes (PTC), 25.3-1976, Code on Safety and Relief Valve Work History Records for MSRV Malfunctions from 1973 to the Presen Licensee Event Reports (LERs) Concerning MSRV Failures from 1983 to the Presen .

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NRC Inspector Inspection Reports (irs) Discussing MSRV Problems (84-11, 84-32, 85-01, 85-03, 85-07, and 85-37).

The review of the above material indicated that the licensee met the guidelines provided by the valve vendor (Crosby) and the commitments contained in the FSAR, and requirements specified in Technical Specifications, and ASME Codes. However, in review of the irs, LERs, and work history relative to MSRV malfunctions, a repetitive failure mode was identified. The failure occurred af ter a unit trip which in turn caused some of the MSRVs to actuate to relieve excessive pressur The problem associated with this MSRV actuation is that on some occasions one or more of the MSRVs failed to reseat at the proper pressure after actuation. In most cases, the control room operator had to reduce main steam header pressure to less than 900 psig to cause the valves to properly reseat (actuation pressures for each of the units 16 MSRVs varies between 1050 and 1104 psig, depending upon the particular valve). This problem was also identified by the Oconee Safety Review Group (OSRG) in their Report 85-09 dated March 18, 198 MSRV reseat pressure is a function of valve design and is defined in terms of percent (%) blowdow The specific valves installed at Oconee, Crosby Model HA-65W size 6R10, are designed for approximately 4% blowdown, which is adjustable by varying the guide ring and nozzle ring setpoint Therefore, the lowest reseat pressure for this installation should be approximately 1000 psig, based on 4% blowdown for the lowest set MSRV value of 1050 11 psig. The review of the work history and LERs also indicated that the majority of the problems were associated with Unit 1 MSRVs, which suggested an age problem aggravated by a lack of preventative maintenance (PM) in the pas Based on the problems associated with the MSRVs, the licensee has established a program to enhance the operating characteristics of the valves which includes the following:

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Technical representatives from the valve vendor provided a train-ing program at the site to familiarize licensee maintenance personnel in proper maintenance of the valves. The licensee plans to incorporate a formal program concerning MSRV repair into the maintenance personnel training progra Through discussions with the valve vendor the licensee is reset-ting the nozzle ring and guide ring setpoints to tighten toler-ances which will lower the % blowdown (setpoints are being modified to +150 notches for the guide ring and -50 notches for

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the nozzle ring).

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The licensee has modified the maintenance and surveillance pro-cedures to more accurately define setting the MSRVs and to require a minimum of two successive satisfactory lift tests for greater accuracy in setpoint determinatio L

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The licensee is presently rebuilding four MSRVs during each refueling outage or major shutdown. To date the following valves have been rebuilt: IMS2, IMS4, IMS10, 2MS13, 2MS14, 2MS15, 2MS16, 3MS2, 3MS8, 3MS10, and 3MS16. Only three Unit I valves were rebuilt because the unit was down for a r.hort outage and the licensee opted to rebuild the valves that wera most prone to failur Responsible licensee engineers also stated that records for maintenance, surveillance and malfunctions would be more accurately documented to improve the historical data available for each valv This area of concern is identified as Inspector Followup Item 269/

85-40-01; Followup on licensees actions to resolve the MSRV blowdown problem. This item may be closed subsequent to a Unit I trip in which the MSRVs actuate and reseat at the proper blowdown pressure. The inspector considers the licensee's actions to correct this problem to be proper and on the right course; however, the best method to ensure the actions have solved the problem is to observe MSRV reseat pressures after a trip, b. Review of the Pressurizer Code Safety Valve Progra ~

The inspection of the pressurizer code safety valve program consisted of interviews with responsible licensee engineers and a review of the test data for each valve provided by Wyle Labs, who are contracted to perform surveillance testing and maintenance on the valve The following areas of the program were discussed:

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The plant has two pressurizer code safety valves installed per unit for a total of six valves and two spare valves which have been tested and refurbished by Wyle Labs are available. The valves are set at 25001 25 psi The current program consists of removing the two valves each refueling outage and replacing them with the two spare valve The removed valves are then sent to Wyle Labs for testing and repair, as required, to continue the cycle. The program, as presently conducted, exceeds the requirements of Technical Specification, Table 4.1-2, which requires only one valve to be tested each refueling outage such that each valve is tested at least once every five year The inspector considers the licensee's program for the pressurizer code safety valves to be acceptable and satisfies regulatory requirement However, one area of concern was identified during this portion of the inspection, which involves how the licensee determines reporta-bility, per 10 CFR 50.73, when the as-found setpoint is determined to be outside the specified tolerance rang This area was addressed in the review of data supplied by Wyle Labs, in which, the

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inspector noted that Wyle Labs had provided " Notices of Anomaly" to the licensee for valves that failed to lift within their specified tolerance range (2500 25 psig). The specific valves noted were serial numbers BT 04976, BL 08890, and BL 08894; all three valves were tested in August 1985, and lifted at 2582, 2388, and 2569 psig, respectivel The inspector questioned the licensee as to the reportability of the anomaly, and at the time was unable to obtain a definitive answer. At the present, the licensee is making a determination regarding the reportability of a pressurizer relief valve that failed to lift within the specified ban This item is identified as Unresolved Item 269/85-40-0 Within the areas examined, no violations or deviations were identifie ,

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