ML17158A349

Discusses GL 89-10,Suppl 5, Inaccuracy of MOV Diagnostic Equipment, & PP&L Response to NRC Request to Notify Staff of Diagnostic Equipment Used to Confirm Proper Size or Establish Settings for safety-related MOVs & Rept Actions

ML17158A349
Person / Time
Site:	Susquehanna
Issue date:	06/14/1994
From:	Poslusny C Office of Nuclear Reactor Regulation
To:	Byram R PENNSYLVANIA POWER & LIGHT CO.
References
GL-89-10, TAC-M88010, TAC-M88011, NUDOCS 9406210240
Download: ML17158A349 (4)

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Docket Nos.

50-387 and 50-388 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 June 14, 1994 Hr. Robert G.

Byram Senior Vice President - Nuclear Pennsylvania Power and Light Company 2 North Ninth Street Allentown, Pennsylvania 18101

SUBJECT:

SUSQUEHANNA STEAM ELECTRIC STATION, UNITS 1

AND 2, GENERIC LETTER 89-10, SUPPLEMENT 5, "INACCURACY OF MOTOR-OPERATED VALVE DIAGNOSTIC E(UIPMENT" (TAC NOS.

M88010 AND M88011)

On June 28, 1993, the NRC staff issued Supplement 5, "Inaccuracy of Motor-Operated Valve Diagnostic Equipment," to Generic Letter (GL) 89-10, "Safety-Related Motor-Operated Valve Testing and Surveillance," requesting nuclear power plant licensees and construction permit holders (1) to re-examine their HOV programs and to identify measures taken to account for uncertainties in properly setting valve operating thrust to ensure operability, and (2) to evaluate the schedule necessary to consider the new information on HOV diagnostic equipment inaccuracy and to take appropriate action in response to that information.

Within 90 days of receipt of Supplement 5 to GL 89-10, licensees were required (1) to notify the NRC staff of the diagnostic equipment used to confirm the proper size, or to establish

settings, for safety-related MOVs, and (2) to report whether they had taken actions or planned to take actions (including schedule) to address

'the new information on the accuracy of HOV diagnostic equipment.

The staff has reviewed the responses, and has found that, for the most part, licensees and permit holders have been actively addressing the uncertainties regarding the accuracy of HOV diagnostic equipment.

The increased inaccuracy of HOV diagnostic equipment can raise questions. regarding (1) the adequacy of torque switch settings to provide sufficient thrust while not exceeding thrust or torque structural limits and (2) the capability of actuator motors at current settings.

In their responses, licensees and permit holders indicated that many HOVs had the potential for underthrusting or overthrusting as a

result of the higher than expected inaccuracy of HOV diagnostic equipment.

Consequently, some licensees reported that HOVs have been retested,

adjusted, or modified to resolve the concerns regarding the accuracy of HOV diagnostic equipment.

In your response dated October 4, 1993, you indicated that PPKL uses MOV diagnostic equipment manufactured by Liberty Technologies.

Further, you stated that the following additional factors affect the accuracy of the VOTES equipment:

(a) reduction in stem transition areas resulting from Liberty Technologies'efinement of its finite element model, (b) changes in effective stem diameters, (c) the need to differentiate between General Purpose ACHE and Stub ACHE threads when determining torque correction factors and effective J Go"-C5 940b210240940b14'(0

Hr. Robert G.

Byram June 14, 1994 t

I stem diameters, and (d) new accuracy values based on torque correction values and percent extrapolation beyond the calibration ranges.

In addition, you stated that the problems specified in Liberty Technologies'art 21 notice, dated October 2,

1992, had been addressed.

Data points outside the calibration range were considered void by PP&L if the Best-Fit-Straight-Line (BFSL) method to calibrate its VOTES equipment was utilized.

In such cases, the uncertainty was considered indeterminate and the VOTES tests were re-performed in most cases.

During a future inspection, the NRC staff will discuss PP&L's resolution of the HOV diagnostic equipment accuracy issue.

Particularly, the NRC staff will discuss (1) the method by which PP&L addressed the Liberty Technologies'art 21 issues and the results of the evaluation, and (2) the method by which PP&L ensured that no operability problems existed as a result of the use,of BFSL outside the calibration range.

This completes all efforts on TAC numbers H88010 and M88011. If you have any questions regarding this issue, please call me at (301) 504-1402.

Sincerely,

/sI cc:

See next page DISTRIBUTION:

Docket File NRC

& Local PDRs PDI-2 Rdg.

SVarga JCalvo CHiller CPoslusny AHansen TScarbrough Chester

Poslusny, Senior Project Manager Project Directorate I-2 Division of Reactor Projects I/II Office of Nuclear Reactor Regulation HO'Brien OGC ACRS(10)

EWenzinger, RGN-I

JWhite, RGN-I OFF1CE PDI-2' PDI-2 D

NANE H

I CPOSLUSNY:tlc CHILLER Ot" DATE OFFICIAL RE R

C Y,'ILENAME:

A:II,SU880 O.GEN 1

94 i< 94

Hr. Robert G.

Byram June 14, 1994 stem diameters, and (d) new accuracy values based on torque correction values and percent extrapolation beyond the calibration ranges.

In addition, you stated that the problems specified in Liberty Technologies'art 21 notice, dated October 2,

1992, had been addressed.

Data points outside the calibration range were considered void by PP&L if the Best-Fit-Straight-Line (BFSL) method to calibrate its VOTES equipment was utilized.

In such cases, the uncertainty was considered indeterminate and the VOTES tests were re-performed in most cases.

During a future inspection, the NRC staff will discuss PP&L's resolution of the HOV diagnostic equipment accuracy issue.

Particularly, the NRC staff will discuss (1) the method by which PP&L addressed the Liberty Technologies'art 21 issues and the results of the evaluation, and (2) the method by which PP&L ensured that no operability problems existed as a result of the use of BFSL outside the calibration range.

This completes all efforts on TAC numbers H88010 and H88011.

If you have any questions regarding this issue, please call me at (301) 504-1402.

Sincerely, cc:

See next page Chester Poslusny Senior Project Hanager Project Director te I-2 Division of Reactor Projects I/II Office of Nuclear Reactor Regulation

Mr. Robert G.

Byram Pennsylvania Power

& Light Company Susquehanna Steam Electric Station, Units 1

& 2 CC:

Jay Silberg, Esq.

Shaw, Pittman, Potts

& Trowbridge 2300 N Street N.W.

Washington, D.C.

20037 Bryan A. Snapp, Esq.

Assistant Corporate Counsel Pennsylvania Power

& Light Company 2 North Ninth Street Allentown, Pennsylvania 18101 Mr. J.

M. Kenny Licensing Group Supervisor Pennsylvania Power

& Light Company 2 North Ninth Street Allentown, Pennsylvania 18101 Mr. Scott Barber Senior Resident Inspector U. S. Nuclear Regulatory Commission P.O.

Box 35 Berwick, Pennsylvania 18603-0035 Mr. William P. Dornsife, Director Bureau of Radiation Protection Pennsylvania Department of Environmental Resources P. 0.

Box 8469 Harrisburg, Pennsylvania 17105-8469 Mr. Jesse C. Tilton, III Allegheny Elec. Cooperative, Inc.

212 Locust Street P.O.

Box 1266 Harrisburg, Pennsylvania 17108-1266 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, Pennsylvania 19406 Mr. Harold G. Stanley Vice President-Nuclear Operations Susquehanna Steam Electric Station Pennsylvania Power and Light Company Box 467 Berwick, Pennsylvania 18603 Mr. Herbert D. Woodeshick Special Office of the President Pennsylvania Power and Light Company Rural Route 1,

Box 1797 Berwick, Pennsylvania 18603 George T. Jones Vice President-Nuclear Engineering Pennsylvania Power and Light Company 2 North Ninth Street Allentown, Pennsylvania 18101