ML20138B247
| ML20138B247 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 12/09/1985 |
| From: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| To: | Taylor J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| References | |
| NUDOCS 8512120250 | |
| Download: ML20138B247 (5) | |
Text
.
BALTI MORE GAS AND ELECTRIC CHARLES CENTER P.O. BOX 1475 BALTIMORE, MARYLAND 21203 ARTHUR E. LUNDVALL. JR.
vice PacssoENT SUPPLv December 9,1985 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 2; Docket No. 50-318 Report of Steam Generator Tube Plugging
REFERENCE:
-(a)
Technical Specifications, Calvert Cliffs Unit 2 ATTACHMENT: (1)
Tubes Plugged #21/#22 Steam Generator (2)
Tube Support Location Drawing Gentlemen:
As required by Technical Specification 4.4.5.5, this letter reports the number of tubes plugged in the Calvert Cliffs Unit 2 Steam Generators during the recent October 1985 Inservice Inspection. Thirteen tubes were found to have service induced degradation which exceeded the Technical Specification plugging limit of 40% loss of nominal wall thickness, nine in #21 Steam Generator and four in #22 Steam Generator. These thirteen tubes were removed from service by plugging the hot and cold leg tube' ends with mechanical tube plugs.
The number of tubes examined by Eddy Current Testing exceeded the requirements of the Calvert Cliffs Unit 2 Technical Specifications. Indications were found on a total of 39 tubes from the approximately 4,512 tubes examined (2,066 #21 steam generator and 2,446 #22 steam generator). As stated above, thirteen of these indications exceeded the plugging limit of 40% loss of nominal wall and required the tube be plugged.
}k ) %/
B512120250 851209 PDR ADOCK 05000318 i
G PDR
Mr. James M. Taylor December 9,1985 Page 2 Attachment (1) lists the tubes plugged during the 1985 Unit ' Refueling Outage along with the reason for plugging the tube. Should you have furth questions regarding this matter, please do not hesitate to contact us.
Very truly yours, h A. E. Lundvall, Jr.
Vice President-Supply AEL/3EM/gla Attachment I
cc:
D. A. Brune, Esquire G. F. Trowbridge, Esquire D. H. Jaffe, NRC T. Foley, NRC i
ATTACHMENT (1)
- 21 Steam Generator Tubes Plugged During the Unit 21985 Outage ROW LINE REASON FOR PLUGGING 14 142 Eddy Current Testing indication of 59 % wall loss originating on the outside diameter of the tube 0.8" above the hot tubesheet (HTS *).
21 141 Eddy Current Testing indication of 52 % wall loss originating on the outside diameter of the tube 1.0" above the hot tubesheet (HTS *).
23 141 Eddy Current Testing indication of '48% wall loss originating on the outside diameter of the tube 0.7" above the hot tubesheet (HTS *).
44 132 Eddy Current Testing indication of 59 % wall loss originating on the outside diameter of the tube 30.0" above the Hi* support.
80 52 Eddy Current Testing indication of 80 % wall loss originating on the outside diamter of the tube 0.6" above the hot tubesheet (HTS *).
132 58 Eddy Current Testing indication of 40 % wall loss originating on the outside diamter of the tube 26" above H3* support.
136 64 Eddy Current Testing indication of 56% and 53% wall loss originating on the outside diamter of the tube 18.1" and 21.5" above the cold tubesheet (CTS *).
139 87 Eddy Current Testing indication of 48 % wall loss originating on the outside diamter of the tube 11.4" above the hot tubesheet (HTS *).
140 86 Eddy Current Testing indication of 48% wall loss originating on the outside diamter of the tube 11.5" above the hot tubesheet (HTS *).
- Reference Attachment (2) for support locations.
ATTACHMENT (1)
- 22 Steam Generator Tubes Plugged During the Unit 21985 Outage ROW LINE REASON FOR PLUGGING 21 5
Eddy Current Testing indication of 43 % wall loss originating on the outside diameter of the tube 32.2" above Hi* support.
34 76 Eddy Current Testing indication of 44 % wall loss originating on the outside diameter of the tube at the diagonal hot (DH*) support.
t 55 139 Eddy Current Testing indication of 67 % wall loss originating on the outside diamter of the tube 11.4" above H4* support.
88 28 Eddy Current Testing indication of 48% wall loss originating on the outside diamter of the tube at the vertical middle (VM*) support.
i-i
- Reference Attachment (2) for support locations.
ATTACHMENT (2)
Figure 1.1 Steam Generator Drawing f
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