ML20133P151

Significant Deficiency Rept SD 414/85-10 Re Failure of Joy Mfg Co Hydrogen Skimmer Fans in Assemblies Designed by Reliance Electronic Co.Initially Reported on 850626.Fans Disassembled for Evaluation.Next Rept Expected by 851101

ML20133P151
Person / Time
Site:	Catawba
Issue date:	07/26/1985
From:	Tucker H DUKE POWER CO.
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
SD-414-85-10, NUDOCS 8508140176
Download: ML20133P151 (3)

Text

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DUKE POWER Goxnav 15.0. Hox m)180 CitAlti.OTTE, N.C. 2(1242 IIAL H. TI'CKER

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July 26, 1985 o u 4, pg , l ,1 -

0 Dr. J. Nelson Grace, Regional Administrator U. S. Nuclear Regulatory Commission i

Region II 101 Marietta Street, NW, Suite 2900 4

Atlanta, Georgia 30323 Re: Catawba Nuclear Station, Unit 2 Docket No. 50-414 Significant Deficiency No. 414/85-10

Dear Dr. Grace:

Pursuant to 10 CFR 50.55(e), please find attached Significant Deficiency Report No. 414/85-10.

Very truly yours, Hal B. Tucker LTP/hrp Attachment cc: Director Office of Inspection and Enforcement INP0 Records Center U. S. Nuclear Regulatory Commission Suite 1500 Washington, D. C. 20555 1100 circle 75 Parkway Atlanta, Georgia 30339 Mr. Jesse L. Riley

' Carolina Environmental Study Group 854 Henley Place Charlotte, North Carolina 28207 J

1 Robert Guild, Esq.

P.O. Box 12097 Charleston, South Carolina 29412 Palmetto Alliance 123515 Devine Street Columbia, South Carolina 29205 NRC Resident Inspector Catawba Nuclear Station g v' 8508140176 850726 PDR ADOCK 05000414 s\

S PDR ZESL9 ..

J Duke Power Company Catawba Nuclear Station Report Number: SD 414/85-10 Report Date: July 26, 1985 Facility: Catawba Nuclear Station Unit 2 Identification of Deficiency:

Hydrogen Skimmer Fan HSF-2A motor failed May 30, 1985 generating Nonconformance Report No. 19720. The second fan motor, HSF-2B, failed June 24, 1985 generating l Nonconformance Report No. 19781. The fan failures occured after approximately 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> of operation. The potential for a defect in a basic component was identified June 25, 1985.

Initial Report:

On June 26, 1985, Mr. C. W. Burger, NRC Region II, Atlanta, Georgia, was notified

, by telephone of the deficiency by L. M. Coggins, T. L. Utterback, R. R. Weidler and C. A. Driggers of Duke Power Company, Charlotte, NC 28242.

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! Component and/or Supplier:

The Hydrogen Skimmer Fans were supplied to Duke Power Company by Joy Manufacturing Company, New Philadelphia, Ohio. The fan assembly was designed and fabricated by Zurn, Kalamazoo, Michigan and the motor is a Reliance Electric, Cleveland, Ohio

, product.

Description of Deficiency:

l Both incidents involved motor bearing failure. Fan HSF-2A shaft end or rear

bearing failed. Fan HSF-2B opposite end or front bearing failed. There is evidence of bearing operation at high temperature in both cases. Both bearing failures resulted in fan wheel and housing damage. Both motors experienced severe shock loads resulting in bent shafts and snapped mounting feet.

Analysis of Safety Implications:

Loss of fan function would prevent post-accident hydrogen from being scavenged in dead-ended lower containment compartments (reference FSAR paragraph 9.4.10).

Prior to failure, Unit 2 equipment received a motor performance test at Reliance

Electric, a fan performance test at Joy Manufacturing Company and was monitored

by Duke Power Company during startup. There was no evidence from these tests that would have led to predicting the failures.

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Similar equipment is used in the Unit I upper containment. Technical Specification

! quarterly' periodic test duration (15 minutes) does not allow this fan-motor to stabilize at operating temperature. Therefore, a problem would not likely show up unless run time is extended.

I Corrective Action:

1 In order to evaluate the failures experienced, Joy and Reliance technical repre-sentatives directed disassembly of the second fan-motor on site June 27 and 28, 1985.

j Preliminary indication suggests two possible causes of failure being damaged

bearing shields causing the balls to " skid" or a lubrication problem causing heat generation and premature failure. Both motors have been shipped to Reliance for t

further evaluation.

Unit 1 equipment was ratested by June 29, 1985 to Duke / Vendor's satisfaction establishing operability. Unit 1 equipment was run for an extended period of time fully instrumented for bearing temperature, vibration, electrical charac-teristics, etc. Unit 2 equipment will be tested in a similar manner when repaired.

j A follow up report will be submitted by November 1,1985.

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