ML20236U021

PN-75-013:Commonwealth Edison Co Notified Region III Ofc of Directorate of Regulatory Operations by Telephone That Small Ultrasonic Indications Found in 4-inch Diameter Bypass Loop Around Discharge Valve of Recirculation Pump

ML20236U021
Person / Time
Site:	Dresden
Issue date:	04/30/1975
From:	Jennifer Davis, Thornburg H, Warnick R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
To:
References
PN-75-013, PN-75-13, NUDOCS 9807290257
Download: ML20236U021 (1)

Text

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oQ>, a lal PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE l April 30, 1975 (1 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PN-75-13 l This preliminary notification constitutes EARLY notice of events of

POSSIBLE safety or public interest significance. The information presented is as initially received without verification or evaluation and is basically all that is known by OIE staff as of 4

00 p.m. on l date of this notification. IT SHOULD BE SPECIFICALLY NOTED THAT THIS NOTIFICATION MAY CONTAIN INFORMATION THAT LATER MAY BE DETERMINED TO BE INACCURATE OR INCONSISTENT. AN OFFICE OF INSPECTION AND ENFORCEMENT NOTIFICATION OF AN INCIDENT OR OCCURRENCE (BLUE SHEET) SUBSEQUENTLY

-WILL BE ISSUED IF WARRANTEL

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'Fa c'ility : Dresden Unit No. 3 Commonwealth Edison Company

Subject:

INDICATIONS IN 4-INCH RECIRCULATION PIPING The Co=monwealth Edison Company notified the Region III office of the Directorate of Regulatory Operations by telephone that small ultrasonic i indications were found in the 4-inch diameter bypass loop around the !_

discharge valve of the recirculation pump at the Dresden - 3 facility. l These indications are characterized as being of weak signal strength and could be due to the geometry and other considerations rather than actual 4' cracks. Indications were from 20% to 100% of the Distance Amplitude i

! .-- Correction reference value. Three indications were observed in the "A" i

!I loop and four'in the "B" loop. i l The licensee had committed to replace all of the 4-inch bypass piping at l

Dresden 2, Dresden 3, Quad-Cities 1 and 2. All of the bypass piping has been replaced at the other three units. The licer.see intends to replace l the piping at the'Dresden - 3 facility during the refueling outage which is in progress.

l r

Contact:

RFWarnick, IE x7261, HDThornburg, IE x7353, JGDavis, IE x7541 o/,

Distribution: 7 l

Chairman Anders Commissioner Mason S. J. Chilk, SECY Commissio,ner Gilinsky. Commissioner Rowden G. F. Murphy, JCAE D(o,-

Commissioner Kennedy C. C. Kammerer, CA - -

L. V. Gossick, EDO D. F. Knuth, IE J. A. Harris, PA ,

B. C. Rusche, NRR H. H. Brown, ISP K. R. Chapman, NMSS H. K. Shapar, ELD Transmitted: P Bldg 'Y 8 ; H St j' ; MD Bldg [ [ 3 O >f t / / #

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9807290257 750430 PDR IbE PN-75-013 PDR ,,

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PRELIMINARY NOTIFICATION - NOT FOR PUBLTc DISCLOSURE