ML20202B117
| ML20202B117 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 02/03/1998 |
| From: | Roche M GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 6L40-98-20005, GL-89-10, NUDOCS 9802110119 | |
| Download: ML20202B117 (6) | |
Text
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GPU Nucleet,Inc.
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U S. Route #9 South NUCLEAR f,**',0ll* **[ **
,,,.a, Tel 609 971-4000 (MN)9714814 February 3. 1998 6L40 98 20005 U.S. Nuclear RegulatoryCommission
. Attention: DocumentControlDesk Washington,DC 20555 Gentlemen:
Subject:
Oyster Creek Nuclear Generating Station (OCNGS)
Docket No. 50-219
_ Facility Operating License No. DPR-16 l
Generic Letter 89-10," Safety-Related Motoi-Operated I.
Valve Testing and Surveillance" This letter provides an updated status of ongoing Oyster Creek Nuclear Generating Station (OCNGS) activities related to NRC Generic Letter (GL) 89-10, " Safety-Related Motor-Operated Valve Testing and Surveillance",as committed in GPU Nuclear letter to the NRC dated August 5, 1997(6730-97-2198).
If any additionalinformation is neede.. please contact Mr. David J. Distel, Corporate Regulatory
. A0 airs,at (973)316-7955.
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. ! ()
Sincerely, b
hL Michael B. Roche Vice Presidentand Director,
. Oyster Creek Attachment
^"'V"~
/DJD Cc: Administrmor,RegionI gl.g
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OCNGS Senior Project Manager OCNGS Senior Residentinspector NRC Region 1 - T. Kenny 9002110119 990203
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PDR ADOCK 05000219 P
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6L40 98 20005 Page I of 5 ATTAClIMENT OCNGS Generic Letter 8910 Motor-Ooerated Valve Procram Status I, Rate of 1,oading (ROL)
Slah!S OCNGS Rate of Loading (ROL) values used to calculate the minimum required measured static thrust setpoint are from the EPRI MOV Performance Prediction Program, EPRI TR-103226. A conservative ROL of 24.3% (5.3% bias with 19% random) is applied to the required design stem thrust to detennine the minin um required measured static thrust setpoint. The random portion,19%, is combined with other uncertainties such as torque switch repeatability and random equipment inaccuracies using the square root sum of the squares method where appropriate.
l The minimum required measured static thrust setpoint is also increased by a 1.2% bias and 4%
random to account for lubricant degradation. This bias is combined with ROL and all other biases.
Existing valve torque switch settings have been verified to be acceptable conside.ing these changes. This item is considered closed.
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.,3 61A0-98 20005 /
Page 2 of 5
- 2. :' Evaluation of Group 3A Valves Using the EPRI PTM -
Status Evaluation of Valves V-21 5 acd V 21 11 using the EPRI Performance Prediction -
Methodology (PPM) has been completed (OPU Nuclear Calculation No. C-1302 900-E540- -
016, Rev. 0). These valves are capable of providing the_ minimunirequired thmst to perform their intended safety function. The minimum required thrust is defined here as the PPM.
- maximum prediction thrust corrected for inherent conservatisms (i.e., thrust uncertainty) where justified. Although the evaluation is complete, additional valve changes are being considered to :
provide improved thrust margins in order to accommodate the PPM maximum predicted thrust.
- These modifications will be completed in the upcoming 17R outage. This item will be closed at that time. -
c-4z 16L40-98 20005?
Page 3 ofS 3.-. Reactor Water Cleanup (RWCU) System Isolatl6n Valve V-16-2 Status I As identified in GPU Nuclear letter to the NRC dated Novembei 5,1997 (6730-97-2246),
- V.16-2 has been added to the scope of the OCNGS GL 89-10, Supplement 3 valves. This valve
- has been modified and is capable of developing sufficient thrust to perform its intended safety
__ function. This item is considered closed, 4
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g-61,40-98-20005 L Page 4 of 5 -
- 4. Include differential pressure effect from EPRI unwedging equation for flex wedge gate valves with an open safety function.
Status GPU Nc:Icar Calculation No. C-1302-900-E540 015, Revision 0, has bien completed and determines the additional unwedging load beyond static and the additional torque for unwedging due to difTerential pressure for all motor-operated gate valves in the GL 89-10 program at OCNGS. This calculation confirmed the current as-left conditions are acceptable and establishes maximum static unseating or seating limits such that future MOV testing ensures unwedging -
capability under differential pressure conditions. This item is considered closed.
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- 6L40-98-20005 Page 5 of 5
- 5. Update Calcul$tions that Use Limitorque Run Emciency to Include Pullout Emciency.
Status Calculations have been revised to include operator pullout emciency in determining the required and available motor torque (C-1302-211-5310-061; C-1302 211-5310-063; C-1302-211-5310-M7; C-
- 1302 215-5310-026; C-1302-215 5310-032: C-1302-212 5310-080). These calculations have -
confirmed the operators are capable of performing their safety function under design basis conditions.
This item is considered closed; 4
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