ML20085F042

AO BFAO-50-259/752W:on 750205,crack Found in 3/4-inch Carbon Steel Test Line on Core Spray Loop II Fullflow Pump Test Loop.Caused by Metal Fatigue Due to Test Connection Line Vibration.Crack Ground Out & Repaired by Welding

ML20085F042
Person / Time
Site:	Browns Ferry
Issue date:	02/15/1975
From:	Eric Thomas TENNESSEE VALLEY AUTHORITY
To:	Case E US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20085F041	List: ML20085F038 ML20085F042
References
NUDOCS 8308180247
Download: ML20085F042 (2)

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TENNESSEE VALLEY AUTHORITY CH ATTANOOGA. TENNESSEE 374ot -

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' '; S .. c' ,U Mr. Edson G. Case "

Acting Director of Licensing U.S. liuclear Regulatory Co=11ssion .

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Washington, DC 20545

Dear Mr. Case:

TEmIESSEE VALLEY AUTHORITY - BROWIIS FERRY ITUCLEAR PLAUT UNIT 1 -

DOCKET NO. 50-259 - FACILITY OPERATING LICENSE DPR ABNORMAL r

OCCURRENCEREPORTBFAO-50-259/752W The enclosed report is to provide details concerning a crack in a 3/4-inchcarbon-steeltestlineonthecoresprayloopIIfull-flow pump test loop and is submitted in accordance with Appendix A to Regulatory Guide 1.16, Revision 1, October 1973. This event occurred on Browns Ferry nuclear Plant unit 1 on February 5, 1975.

Very truly yours, TENUESSEE VALLEY AUTHORITY E. F. Thomas

Director of Power Production

} Enclosure j CC (Enclosure):

Mr. Norman C. Moseley, Director U.S. Nuclear Regulatory Commission i Regional Office 230 Peachtree Street, NW., Suite 818 Atlanta, Georgia 30303 l

8308180247 750207 PDRADOCK05000{g {3 'g[<f S / 1772 i.

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( ABNOPPAL OCCURRENCE REPORT i

Report No.:

Report Date: EFAO-50-259{752W February 1 , 1975 Occurrence Date: February 5, 1975 Facility: Browns Ferry Nuclear Plant unit 1 g Identification of Occurrence Acrackina3/4-inchcarbon-steeltestlineonthecoresprayloopIIfull-flow pump test loop.

( Conditions Prior to Occurrence The unit was in the cold ahutdown condition.

( Description of Occurrence

- a functional leak test of the core spray piping, a leak was discovered During/4-inch in a 3 carbon-steel test connecticn on the pu=p flow test loop piping outside the containment boundary. The leak resulted from a crack in a socket veld to test valve No.75-591.

4 Designation of Antarent Cause of _ Occurrence The apparent cause of the crack was metal fatigue due to vibration of the test

connection line, Analysis of Occurrence No damage to systems, co=ponents, or structures was experienced; no personnel injuries or exposures were involved; no radioactive materials were released; and there were no adverse effects to the public health and safety as a result of this occurrence. The core spray loop was capable of performing its k intended function with this small leak.

Corrective Action The crack was ground out and repaired by velding. Additional support for the test connection was provided to irtibit vibration. After the repair was completed, a functional leak '. cst was satisfactorily performed. A surveillcnce test was perfor=ed to ensure that the core sprey loop II was operable, Failure Datt

. BFAO-50-260/7419W (crack in a 2-inch bypass line)

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