ML19224D529
| ML19224D529 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 06/25/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Boyer V PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| References | |
| NUDOCS 7907120522 | |
| Download: ML19224D529 (1) | |
Text
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UNITED STATES
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KING OF PRUSSI A, PENNSYLVANI A 1940G June 25, 1979 Docket Nos. 50-352 50-353 Philadelphia Electric Company Attention:
Mr. V. S. Boyer Vice President Engineering and Research 230'l Market Street Philadelphia, Pennsylvania 19101 Gentlemen:
The enclosed Bulletin 79-13 is forwarded to you for information. No written response is required.
If you desire additional information regarding this matter, please contact this office.
Sincerely, a1ntt'p $l-Ya&L-yce H. Grier irector
Enclosures:
1.
IE Bulletin No. 79-13 w/ Attachments 2.
List of IE Bulletins Issued in Last 12 Months ici n.., o
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ENCLOSURE 1 UNITED STATES NUCLEAR REGULATORY C0f!'11SSION OFFICE OF INSPECTION AFD ENFORCEfENT WASHINGTON, D.C.
20555 IE Bulletin No. <9-13 Date: June 25 1979 3
Page 1 of 4 CRACKING IN FEEDWATER SYSTEf1 PIPING Description of Circunstances:
On fiay 20, 1979, Indiana and flichigan 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 ffay 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 ffay 25, 1979, a letter was sent to all PWR licensees by the Office of Nuclear Reactor RegulatNn which informed licensees of the D. C. Cook failures and requested specific information on feedwater systen design, fabrication, inspection and operating histories. To further explore the generic nature of the cracking problem, the Office of Inspection and Enforcement remested licensees of PWR plants in current outages to immediately conduct volumetric examination of certain feedwa_'r piping welds.
As a result of these actions, several other licensees with Hestinghouse 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.
Misconsin Public Service company decided on June 20, 1979 to cut out a feedwater qozzle-to-pipe weld which contained questionable indication, for metallurgic 91 examination.
As of June 22, 1979 and since fiay 15, 1979 seven other PUR #a<ilities have inspected the feedwater nozzle-to-pipe welds without finding craf.ing indications.
The feedwater nozzle-to-pipe configurations for D.C. Ccok and for San e shown on the attached figures 1 and 2.
A typical feedwate #
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weld joint detail showing the principal crack 3, 'e are shown on the attached figure 3. p DoCOMEl T tered On ?! arch 17, 1977, during heat-up fo D iU the 16-inch diameter feedwater pipinhEnti" docum@t 9reV Unit 1, a leak was discovered in the~
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nondestructive examination of all noz intg s,_ l so g pageS-B,J l