ML20057B589

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Responds to NRC GL-89-10,Suppl 5,identifying Test Equipment Which Has Been Utilized at Plant to Date & Summarizing Actions Taken to Address Inaccuracy Issues Associated W/Use of Equipment
ML20057B589
Person / Time
Site: Vogtle  Southern Nuclear icon.png
Issue date: 09/15/1993
From: Mccoy C
GEORGIA POWER CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-89-10, LCV-0136, LCV-136, NUDOCS 9309220276
Download: ML20057B589 (5)


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I LCV-0136 Docket No. 50-424 50-425 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555 Gentlemen:

VOGTLE ELECTRIC GENERATING PLANT NRC GENERIC LETTER 89-10 SUPPLEMENT 5 RESPONSE Pursuant to the requirements of NRC Generic Letter 89-10, Supplement 5, Georgia Power Company (GPC) has re-evaluated the potential inaccuracy issues associated with the use of motor-operated valve (MOV) diagnostic test equipment at Vogtle Electric Generating Plant (VEGP). The purpose of this response is to identify the test equipment which has been utilized at VEGP to date and to summarize the actions taken to address inaccuracy issues associated with the use of this equipment.

Vogtle Electric Generating Plant began utilizing motor-operated valve diagnostic test equipment to setup safety-related valves prior to commercial operation. The plant initially utilized the MOVATS 2000 Series of equipment which is an oscilloscope-based system utilizing the Thrust Measurement Device (TMD) as its primary thrust measurement sensor. The plant later upgraded to the MOVATS 3000 Series of equipment which is a computer-based system designed to utilize a variety of sensors. VEGP has performed valve testing with the MOVATS 3000 Series equipment utilizing the TMD, the Stem Strain Transducer, the Stem Strain Ring, the Stem Load Sensor and the Torque Thrust Cell. In addition, VEGP has utilized the MOVATS Butterfly Analysis and Review Test System (BARTS)in conjunction with the 2000 and 3000 Series data acquisition systems to perform testing on butterfly valves.

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LCV-0136 Page Two Valve Operation Test & Evaluation System (VOTES) diagnostic test equipment was subsequently procured from Liberty Technology and VEGP began using this equipment as its primary MOV test system in the Spring 1993 Unit I refueling outage. The VOTES test equipment is a computer-based system which utilizes the VOTES Force Sensor as its primary thrust measurement sensor. In addition, the VOTES test equipment is compatible with the VOTES Torque Cartridges, which are capable of measuring operator output torque, and Torque Plugs, which are used in performing tests on butterfly valves.

It is the intention of VEGP to utilize the VOTES test system to perform all rising stem motor-operated valve testing in the future. The MOVATS TMD may be utilized as an auxiliary sensor to provide an indication of operator output torque and/or for diagnostic purposes. However, the TMD will not be utilized as a primary thrust measurement sensor. In addition, at least one MOVATS system will remain operational to support butterfly valve testing since VOTES equipment is not currently available to test Limitorque H3BC quarter-turn actuators.

With regard to the potential inaccuracies associated with the MOVATS TMD-based test equipment relative to the open vs. close issue, Georgia Power Company (GPC) has evaluated and dispositioned each of the VEGP Generic Letter 89-10 valves setup utilizing this equipment. The enclosure to this letter summarizes the results of this evaluation.

With regard to the potential inaccuracies associated with the VOTES test equipment, ,

relative to the material properties and the torque etTect, GPC has determined that this ,l issue is not applicable to VEGP. VOTES addressed both the material properties and i torque efTect issue in Release 2.3 of the VOTES software. VEGP did not perform testing )

with the VOTES system prior to the identification of these problems and the subsequent release of the revised software, therefore, the potential for this problem to have occurred at VEGP did not exist.

Information Notice 93-54 was issued on July 20,1993 by the NRC and addressed a potential inaccuracy associated with the MOVATS Torque Thrust Cell. The Information Notice indicated that the potential existed for variations in torque and thmst output  ;

between the measured values with the Torque Thrust Cell installed and the actual values following removal of the Torque Thrust Cel!. MOVATS subsequently issued Special Test Report 6.0 dated August 6,1993 entitled, " Actuator Repositioning Effects Test Report" The Special Test Report documents the results of testing performed by MOVATS to  !

address this concern and includes revised accuracy figures for the Torque Thrust Cell.

The transmittal letter included with the report indicates that MOVATS Engineering Report 5.0, which documents the accuracy of all MOVATS sensors, will be revised to include the updated accuracy figures.

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GeorgiaPower d U. S. Nuclear Regulatory Commission LCV-0136 Page Three The only use of the Torque Thrust Cell to perform MOV testing at VEGP was during the Spring 1992 Unit 2 refueling outage. VEGP does not plan to use the Torque T hrust Cell in the future to perform MOV testing. GPC was unaware of the potentialinaccuracy concerns related to the repositioning issue until the Information Notice was issued. The issue is being reviewed at this time and GPC will evaluate and disposition any affected valves at VEGP by the conclusion of the Fall 1993 Unit 2 refueling outage. -

Mr. C. K. McCoy states that he is a vice president of the Georgia Power Company and is authorized to execute this oath on behalf of Georgia Power Company and that, to the best of his knowledge and belief, the facts set forth in this letter and attachments are true.

GEORGIA POWER COMPANY By: ', ,

C. K. M'cCoy /

Sworn to and subscribed before me this of . . _!993 hotar Public uune;mawnwGMM %

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Enclosure:

MOVATS TMD Open vs. Close Evaluation Summary j xc: Georgia P_pwer Compsy Mr. J. B. Beasley, Jr. (w/o encl.)

Mr. M. Sheibani (w/ encl.)

NORMS (w/ encl.)

1]L S. Nuclearlegulatpry Commission Mr. S. D. Ebneter, Regional Administrator (w/ encl.)

Mr. D. S. Ilood, Licensing Project Manager, NRR (w/ encl.)

Mr. B. R. Bonser, Senior Resident Inspector, Vogtle (w/ encl.)

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Enclosure to GPC Letter LCV-0136 MOVATS TMD Open vs. Close Evaluation Summary Each of the valves included within the scope of the VEGP Generic Letter 89-10 program which were setup utilizing the MOVATS TMD test equipment have been evaluated in accordance with MOVATS Engineering Report 5.2, Revision 0 dated March 13,1992.

The evaluations were prioritized with the IEB 85-03 valves being evaluated initially followed by the remainder of the GL 89-10 valves.

The evaluation of the IEB 85-03 valves was completed July 17,1992. As a result of this review the folicwing three valves were identified with switch settings potentially outside the valve setup window:

Tac No. Descrintion iFV-5154 Auxiliary Feedwater (AFW) Miniflow Valve IFV-5155 AFW Miniflow Valve 211V-8821 A Safety Injection (SI) to Reactor Coolant System (RCS) Isolation Valve These valves cach had close torque switch settings that potentially exceeded the valve or operator maximum allowables. Additional evaluations determined that valves IFV-5154 and IFV-5155 would be acceptable for continued operation indefmitely in their "as-left" configuration. It was determined that valve 2HV-8821 A would be acceptable for 100 cycles in its "as-left" configuration but that the operator would require disassembly and inspection at the next scheduled refueling outage. Valves IFV-5154 and IFV-5155 were subsequently retested and setup utilizing VOTES test equipment during the Spring 1993 Unit I refueling outage and 2HV-8821 A will be inspected and setup during the upcoming Fall 1993 Unit 2 refueling outage.

The evaluation of the remaining GL 89-10 valves was completed September 10,1992. As a result of this review, four additional valves were identified with switch settings potentially outside the valve setup window:

Tac No. Description 1HV-3548 RCS Sample Valve 1HV-8716A Residual Heat Removal (RHR) Hot Leg Isolation Valve IHV-8804B RHR to SI Suction Valve lHV-9001B Containment Spray Discharge Valve

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Enclosure to )

GPC Letter LCV-0136

'l MOVATS TMD Open vs. Close Evaluation Summary (continued)

These valves also had close torque switch settings which potentially exceeded the valve or 1 operator allowable. Additional evaluations concluded that each of the valves would be acceptable for continued operation indefmitely in their "as-left" configuration. These valves were subsequently retested and setup utilizing VOTES test equipment during the Spring 1993 Unit I refueling outage.

Subsequent to the completion of the above referenced evaluations it was determined that an error had been made in calculating the close torque switch settings, based on the revised accuracy's, for valves lHV-19055 and 1HV-19057. This occurrence was explained in Licensee Event Report (LER) 50-424/1992-009 dated December 7,1992.

Due to these errors, a review was undertaken to identify any additional problems associated with the MOVATS open vs. close evaluations. The review was completed  :

December 18,1992 with no additional errors being identified. It was concluded that the problem with illV-19055 and lHV-19057 was due to a data transposition error and that ,

the error was an isolated occurrence.

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