ML19224D557
| ML19224D557 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 06/25/1979 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Gary R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| References | |
| NUDOCS 7907120604 | |
| Download: ML19224D557 (1) | |
Text
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UNITED STATES S\\f f,
[,'n NUCLEAR REGULATORY COMMISSION 5,f'. G /c' c,5 REG!ON IV gg;j g,fwphagU
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G11 RYAN PLAZA DRIVE, SUITE 1000 o
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June 25, 1979 In Reply Refer To:
RIV Docket No. 50-445/IE Bulletin 79-13 50-446/IE Bulletin 79-13 Texas Utilities Generating Company ATTN:
Mr. R. J. Gary, Executive Vice President and General Manager 2001 Bryan Tower Dallas, Texas 75201 Gentlemen:
The enclosed IE Bulletin 73-13 is forwarded to you for information. No written response is required.
If you desire additional information regarding this matter, please contact this office.
Sincerely, f
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ef Lui Karl V. Seyfrit Director
Enclosures:
1.
Listing of IE Bulletia Issued in Last 12 Months
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'm 4l4 069 790712060[
UNITED STATES NUCLEAR ?IGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Bulletin No. 79-13 Date: June 25, 1979 Page 1 of 4 CRACKING IN FEEDWATER SYSTEM PIPING Description of Circumstances:
On May 20, 1979, Indiana and Michigan Power Company notified the NRC of cracking in two feedwater lines at their D. C. Cook Unit 2 facility. The cracking was discovered following a shutdown on May 19 to investigate leakage inside containment.
Leaking circumferential cracks were identified in the 16-inch feedwater elbows adjacent to two steam generator nozzle elbow welds.
Subsequent radiographic examination revealed crack indications in all eight steam generator feedwater lines at this location on both Units 1 and '.
On May 25, 1979, a letter was sent to all PWR licensees by the Office of Nuclear Reactor Regulation which informed licensees of the D. C. Cook failures and requested specific information on feedwater system design, fabrication, inspection and operating histories. To further explore the generic nature of the cracking problem,-the Office of Inspection and Enforcement requested licensees of PWR plants in current outages to immediately conduct volumetric examination of certain feedwater piping welds.
As a result of these actions, several other licensees with Westinghouse steam generators reported crack indications.
Southern California Edison reported on June 5, 1979, that radiographic examination revealed indications of cracking in feedwater nozzle-to piping welds on two of three steam generators of San Onofre Unit 1.
On June 15, 1979, Carolina Power and Light reported that radiography showed crack indications in similar locations at their H. B. Robinson Unit 2.
Duquesne Power and Light confirmed on June 18, 1979, that radiography has shown cracking in their Beaver Valley Unit 1 feedwater piping to vessel nozzle weld.
Public Service Electric and Gas Company reported on June 20, 1979 that Salem Unit 1 also has crack indications. Wisconsin Public Service Company decided on June 20, 1979 to cut out a feedwater nozzle-to pipe weld which contained a questionable indication, for metallurgical examiation.
As of June 22, 1979 and since May 25, 1979 seven other PWR facilities have inspected the feedwater nozzle-to pipe welds without finding cracking indications.
The feedwater nozzle-to pipe configurations for D.C. Cook and for San Onnfro we
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shown on the attached Figures 1 W 9 a -
joint detail showing the princiI DUPLICATE DOCUMENT y
are shown on the attached Figure b
' Entire document previously entered into system under:
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on March 17, 1977, during heat-u
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1 Unit 1, a leak was discovered in the 16-inch diameter feedwater p ANO lh/ b 7l 6"c j
nondestructive examination of al 4
No. of pages:
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414 089 j
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