ML19256B487
| ML19256B487 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/25/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Jeffery Grant TOLEDO EDISON CO. |
| References | |
| NUDOCS 7907130150 | |
| Download: ML19256B487 (1) | |
Text
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UNITED STATES l
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June 25, 1979 e
Docket No. 50-346 Toledo Edison Company ATTN:
Mr. James S. Grant Vice President - Energy Supply Edison Plaza 300 Madison Avenue Toledo, OH 43652 Gentlemen:
Enclosed is lE Bulletin No. 79-13 which requires action by you with regard to your power reactor facility with an operating license.
Should you have any questions regarding this Bulletin or the actions required by you, please contact this office.
Sincerely, ames G. Keppler Director
Enclosures:
- 2. List of IE Bulletins Issued in Last 12 Months cc w/encls:
Mr. T. Murray, Station Superintendent Central Files Director, NRR/ DPM Director, NRR/ DDR PDR Local PDR NSIC TIC Harold W. Kohn, Ohio Power Siting Commission 7907130 M
U.S. NUCLEAR REGULATouY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT REGION III June 25, 1979 IE Bulletin No. 79-13 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 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 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 irlications. 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 Leaver 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 our a feedwater nozzle-to-pipe weld which contained questionable indication, for metallurgical examination. As of June 22, 1979 and since May 25, 1979 seven other PWR facilities have inspected the feedwater nozzle-to-pipe welds without finding crac1".ng indications.
The feedwater nozzle-to-pipe configurations for D.C. Cook and for San Onofre are shown on the attached figures 1 and 2.
A typical feedwater pipe-to-nozzle veld joint detail showing the principcl crack locations for D.C. Cook and San Onofre are shown on the attached figure 3.
On March 17, 1977, during heat-up for h Unit 1, a leak was discovered in the ve DUPLICATE DOCUFERPr the 16-inch diameter feedwater piping t nondestructive examination of all nozzl Entire doctunent previously entered into system under:
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