ML20134A003
| ML20134A003 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 08/08/1985 |
| From: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| To: | Taylor J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| References | |
| NUDOCS 8508150142 | |
| Download: ML20134A003 (3) | |
Text
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BALTIMORE GAS AND ELECTRIC CHARLES CENTER. P. O. BOX 1475. BALTIMORE, MARYLAND 21203 ARTHun E. LUNDVALL, JR.
VicE PatsMNT SuppLv August 8,1985 U.S. Nuclear Regulatory Commission Office of Inspection & Enforcement Washington, DC 20555 ATTENTION:
Mr. James M. Taylor, Director
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit 1; Docket No. 50-317 Report of Steam Generator Tube Plugging
REFERENCE:
(a)
Technical Specifications, Calvert Cliffs Unit 1 (b)
Letter to James M. Taylor, from A. E. Lundvall, Jr., dated May 28,1985 ATTACHMENT:(1)
Tubes Plugged #11/#12 Steam Generator Gentlemen:
This letter supplements Reference (b), which provided an initial report of Steam Generator Tube Plugging. Additional Eddy Current Testing (ECT) was performed on Unit 1 due to the extended outage caused by the Unit I main generator repairs. Three additional tubes were found to have service induced degradation which exceeded the Technical Specification plugging limit of 40% loss of nominal wall thickness, one in #11 Steam Generator and two in #12 Steam Generator.
The number of tubes examined by ECT were in addition to the 11,070 tubes examined in May 1985 as reported in Reference (b). Indications of 20% thru wall degradation or greater were found on a total of 144 tubes from the approximately 5,832 additional tubes examined (3,270 - #11 Steam Generator and 2,562 - #12 Steam Generator). As stated above, three of these indications exceeded the plugging limit of 40% loss of nominal wall and required the tube to be plugged. The indications were all of a small volume and small area nature.
8508150142 850808 PDR ADOCK 05000317 S
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r Mr. James M. Taylor August 8,1985 Page 2 Attachments (1) list the additional tubes plugged during the extended 1985 Unit 1 outage along with the reason for plugging the tube. Should you have further questions regarding this matter, please do not hesitate to contact us.
Very trul" vours, 7
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,( '( f h* dL AEL/JEM/gla Attachment cc:
- 3. A. Biddison, Esquire G. F. Trowbridge, Esquire D. H. Jaffe, NRC T. Foley, NRC
r' ATTACHMENT (1)
- 11 Steam Generator Tubes Plugged During the Unit 1 July 1985 Extended Outage LINE ROW REASON FOR PLUGGING 111 53 Eddy Current Testing indication of 45% wall loss originating
.4 inches above the hot tube sheet.
- 12 Steam Generator Tubes Plugged During the Unit 1 July 1985 Extended Outage LINE ROW REASON FOR PLUGGING 58 56 Eddy Current Testing indication of 57% wall loss originating
.7 inches above hot tube sheet 60 56 Eddy Current Testing indication of 53% wall loss originating
.5 inches above hot tube sheet r
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