ML19246B214
| ML19246B214 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Byron, Braidwood, Quad Cities, LaSalle  |
| Issue date: | 06/25/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Brian Lee COMMONWEALTH EDISON CO. |
| References | |
| NUDOCS 7907120680 | |
| Download: ML19246B214 (1) | |
Text
{{#Wiki_filter:i / (g UNITED STATES f. ?' NUCLEAR REGULATORY COMMISSION }{ g-{f. [ [I j;, j REGION 111 799 ROOSE V E LT RO AD e 3 fg . sg GLE N E LLY N. IL LINOIS 60137
- g June 25, 1979 Docket Nos. 50-10, 50-237, 50-249, Su '54, 50-265, 50-373, 50-374, 50-45;, 50-455, 50-456, and 50-457 C"mmonwealth Edison Company PTN:
Mr. Byron Lee, Jr. Vice President Post Of fice Box 767 Chicago, IL 60690 Gentlemen: The enclosed IE Bulletin No. 79-13 is forwarded to you for information. No written response is required. If you desire additional information regarding this matter, please.ntact this office. 51acerely, /\\ g bJ. R / / / ames G. Keppler ' Director
Enclosures:
1. IE Bulletin No. 79-13
- 2. Listing of IE Bulletins Issued in Last 12 Months cc w/encls:
Mr. B. B. Stephenson, Mr. R. Cosaro, Project Station Superintendent Superintendent Mr. N. Kalivianakis, Central Files Station Superintendent Director, NRR/ DPM Mr. L. J. Burke, Site Director, NRR/ DOR Project Superintendent PDR Mr. T. E. Quaka, Quality Local PDR Assurance Supervisor NSIC Mr. R. H. Holyoak, Station TIC Superintendent Anthony Roissan, Esq., Mr. Gunner Sorensen, Site Attorney Project Superintendent Mr. Dean Hansell, Office of Assistant Attorney General Oil 9 3,. g; vi < m 7 9 0 71~0 0 ' ^ LTgo
U.S. NUCLEAR REGULAT0nY CO.T!1SSION OFFICE OF INSPECTION AND ENFORCE!!ENT 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 examina'. ion 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 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 I feedwater piping to vessel nozzle weld. Public Service Electric and Gas Company report,ed 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 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 cracking 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 weld joint detail showing the principal crM 1 -"~ N G " are shown on the attached figure 3. 4 DUPLICATE DOCUMENT x On March 17, 1977, during heat-up forj Entire document previously entered 1, a leak was discovered in the t ' Unit the 16-inch diameter feedwater piping into system under: nondestructive examination of all nozi ANO 7 O No. of Pages: O g n q, 1 4 7 7 C; is f: v JJ 1._ _._l' i ' vo625g 3 4 g}}