ML19254E298
| ML19254E298 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 10/17/1979 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Gary R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| References | |
| NUDOCS 7910310427 | |
| Download: ML19254E298 (1) | |
Text
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UNITED STATES
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NUCLEAR REGULATORY COMMISSION U*
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%,r October 17, 1979
.....f In Reply Refer To:
RIV Docket No.
50-445/IE Bullet.in No. 79-13 (Rev. 2) 50-446/IE Bulletin No. 79-13 (Rev. 2)
Texas Utilities Generating Cor pany ATTN:
Mr. R. J. Gary, Executive Vice President and General Manager 2001 Bryan Tower Dallas, Texas 75201 Gentlemen:
The enclosed IE Bulletin 79-13, Revision 2 is forwarded to you for information. No written response is required.
If you desire additional information regarding this matter, please contact this office.
Sincerely, ll
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Karl V. Seyfri /
Director
Enclosures:
1.
IE Bulletin No. 79-13, Revision 2 2.
List of IE Bulletins Issued in the Last Six Months 1248 260
'T 910 310 f-2_.7,
SSINS:
6830 Accession No.:
7908220135 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Bulletin No. 79-13 Revision 2 October 16, 1979 Page 1 of 5 CRACKING IN FEEDWATER SYSTEM PIPING Description of Circumstances:
This revision to IE Bulletin No. 79-13 is based on the results of the radio-graphic examinations and ongoing investigation of the subject problem to date since the initial Bulletin was issued. The revision reduces in scope the R2 number and extent of the piping system welds required to be examined. The requirements for reporting and action time frare remain nachanged.
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 follcwing 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.
S.. ;_quent radiographic examination revealed crack indications in all eight steam generator feedwater lines at this location on both Units 1 and 2.
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 hi stories. To further explore the generi' rature 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-pipe 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 Powe r and Lic " -- -- ' -- '--- ' '
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radiography has shown cracking in their to-vessel nozzle weld. Public Service NOTE: R1 and R2 indicates lines revise Entire document previously entered into system under:
M2MIC 1248 261
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