05000298/LER-1980-041, Forwards LER 80-041/03L-0

Forwards LER 80-041/03L-0

ML19353A229
Person / Time
Site:	Cooper
Issue date:	11/14/1980
From:	Lessor L NEBRASKA PUBLIC POWER DISTRICT
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19353A230	List: 05000298/LER-1980-041, Forwards LER 80-041/03L-0 05000298/LER-1980-041-03, /03L-0:on 801016,svc Water Pump C Noted Vibrating Excessively.Cause Undetermined.Pump Disassembled & Rotating Assembly Returned for Overhaul.Other Components Reused
References
CNSS800689, NUDOCS 8101070514
Download: ML19353A229 (2)

LER-1980-041, Forwards LER 80-041/03L-0

Event date:
Report date:
2981980041R00 - NRC Website

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I yg ] Nebraska Public Power District COOPER NUCLEAR STATION 4 ;j -

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t CNSS800689 November 14, 1980 1

Mr. K. V. Seyfrit, Director U.S. Nuclear Regulatory Coenission 7 --

Cffice of Inspection and Enforcement Region IV

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611 Ryan Plaza Drive Suite 1000 f

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I Arlington, Texas 76011 55

Dear Sir:

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This report is submitted in accordance with Section 6.7.2.3.2 of the Technical Specifications for Cooper Nuclear Station and discusses a reportable occurren p that was discovered on October 16, 1980. A 11-censee event report form is also encicsed.

Report No.:

50-298-80-41 Report Date:

Nove=ber 14, 1980 Occurrence Date: October 16, 1980 Facility:

Cooper Nuclear Station Brc,wnville, Nebraska 68321 Identification of Occurrence:

Conditions leading to operation in a degraded mode permitted by a limiting condition as delineated in Section 3.12.C.2 of the Tech-nical Specifications.

Conditions Prior to Occurrence:

Steady state power operation at approximately 99% of reactor power.

Deacription of Occurrence:

During normal operation, an operator noticed the "C" Service Water Pump was vibrating excessively.

Designation of Apparent Cause of Occurrence:

The Service Water pumps are Model 28KXL, single stage vertical lif t pumps manufactured by the Byron Jackson Pump Division of Borg Warner. The subject pump was disassembled to determine the origin of the vibration. During disassembly, no abnormalities were dis-covered. There is not an apparent cause for this occurrence as no component defects were found.

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3 Mr. K. V. Seyfrit i

November 14, 1980 j

Page 2.

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Analysis of Occurrence:

1 There are four (4) service water pumps, two (2) per service water i

loop. The three (3) remaining pumps were operable. The subject pump was operating satisfactorily at the time it was secured to investigate the high vibration problem. One service water pump is a

required for accident conditions.

Immediately af ter declaring the pump inoperable, surveillance tests to prove operability of the remaining pumps and service water valves were commenced. This event presented no adverse consequences from the standpoint of public health and safety.

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Corrective Action

l The subject pump was overhauled which included replacing the ro-tating assembly in the pump bowl. Upon reassembly, the pump was i

proven operable with no excessive vibration. The rotating assembly f

for the subject pump was returned to the manufacturer for overhaul.

Prior to this work the assembly will be checked for imbalance. An updated report will be submitted if a discrepancy is noted by the

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manufacturer.

Sincerely, W-t~

L. C. Lessor 1

Station Superintendent i

Cooper Nuclear Station LCL:cg i

Attach.

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