ML20084J675

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Ao:On 730424,during Surveillance Test of B Isolation Condensor Motor Operated Condensate Return Valve V-14-35, Breakaway from Closed Motor Current of 75 Amps Observed. Cause Undetermined.Torque Applied to Handwheel Freed Disc
ML20084J675
Person / Time
Site: Oyster Creek
Issue date: 04/24/1973
From: Ross D
JERSEY CENTRAL POWER & LIGHT CO.
To: Anthony Giambusso
US ATOMIC ENERGY COMMISSION (AEC)
References
NUDOCS 8305180649
Download: ML20084J675 (5)


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Subject:

Oyster Creek Station

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,J Docket No. 50-219

s Isolation Condenser Valve Failurc This event is considered to be an abnormal occurrence as defined in k h/0) the Technical Specification, Paragraph 1.15.F.

g-During the weekly surveillance test of the "B" isolation condenser motor operated condensate return valvo V-14-35, a " breakaway from closed" O

motor current of 75 amps was observed. The high current continued for about 5 seconds whereupon the breaker was manually tripped. The reactor was in the cold shutdown cendition at the time of this test.

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Investigation is still in progress in an effort to determine the cause of this fcilure.

Ikwever, as was the case upon the previous failure on

. -7 December 29, 1972, the valvo disc was finally freed from its seat only upon

,d s applying considerabic torque to the operater handuhccl.

Once frec, the valvo' k

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was stroked with the motor operator to the fully opened, and then fully closed

-position several times without any difficulty. This valve had previously been b#

stroked successfully on sixtcon separato occasions' during the weekly survoillance

'T tests.

In all but one case, the reactor was operating at pressure and temper-U atures associated with full power operation.

In addition, during this period, the "B" isolation. condensor was actuated on one occasion to assist in maintain-ing plant pressure during a shutdown. The valve and operator data are as follows:

Valve Manufacturer: Anchor Size:

10" h' edge Gate i

Rating: 600 pounds Operator Manufacturer: Philadelphia Gear Company / Peerless lilectric-Operator Type: SNV Sizo 2 Motor Rating:

4.3 h.p. G 1900 rpm,125 volts DC, 35 amps f

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f ~.lll 27 %

$$Pi!88fo k g

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COPY SENT REGION o

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Mr. Giambusso April 24,1973 The requirements for at least one of the isolation condensers to act as a means of heat removal it detailed in Amendment 67 to the Oyster Creek FDSAR.

Since the "II" isolation condenser would not have been able to fulfill this requirc:.:ent, the significance of this event is that the isolation condenser systen would not have had its desi ;ned redundancy.

Both the va]ve nanufacturer and the associated operator nanufacturer have been contacted to aid in our investi;ation of this failure during our t

present outage.

Additional informatien will be forwarded to your office as soon as it becomes available.

Enclosed are forty (40) copies of this report.

Very truly yours,

O.+ L (It~f u l j'i~ &Li_

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Donald A. 11oss Manager, Nuclear Generating Stations DAR:cs linclosures (40) cc:

Mr. J. P. O'Reilly, Director Directorate of Regulatory Operations, llegion I I