ML20083Q233
| ML20083Q233 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 05/18/1995 |
| From: | Miller D NORTHEAST NUCLEAR ENERGY CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| MP-95-162, NUDOCS 9505250204 | |
| Download: ML20083Q233 (2) | |
Text
w Northe st Rope Ferry Rd. (Route 156), Waterford, CT 06385 Nuclear Energy Mmstone Nuclear Power Station Northeast Nuclear Energy Company 1
P.O. Box 128 Waterford, CT 06385-0128 (203) 447 - 1791 Fax (203) 444-4277 The Northeast Utilities System May 18, 1995 MP-95-162 Docket No. 50-423 RE: 10CFR50.36 U.S. Nucioar Rogulatory Commiccion Attn: Document Control Desk Washington, D.C. 20555 Millstone Nuclear Power Station Unit No. 3 Steam Generator Tube Plugging Gentlemen:
The special report is being submitted pursuant to the requirements of Plant Technical Specifications 4.4.5.5.a and 6.9.2. Plant Technical Specification 4.4.5.5.a requires that a special report be submitted to the commission within 15 days following completion of each inservice inspection of the steam generator tubes, to document the number of tubes plugged in each generator.
The eddy current inspections, conducted at the end of Cycle 5, were completed on May 9,1995. Table 1 provides a brief synopsis of the results of the steam generator tube inspection. A total of 8473 tubes or 38 percent of the total tubes in all generators were inspected. The inspections were performed in Steam Generators B and D. Eddy Current testing identified flaws greater than or equal to the plugging limit in eleven tubes. The plugging limit is defined in Technical Specifications as an Imperfection de ath of 40 percent of nominal tube wall thickness. All eleven tubes exhibited degradaton attributed to Anti-vlbration Bar (AVB) wear. These tubes are identified on Table 2 and were removed from service utilizing Westinghouse Alloy 690 tapered mechanical plugs. Table 3 provides a summary of the total tubes plugged to date.
The complete results of the steam generator tube inspection will be submitted within 12 months in accordance with Plant Technical Specification 4.4.5.5.b.
The licensee contact for this special report is Larry Loomis who may be reached at (203)444-5468.
Very truly yours, NORTHEAST NUCLEAR ENERG COMP NY Y
Donald B. Miller, Jr.
Vice President - Millstone Station DBM/RLM:ljs 9505250204 95o51s
[
PDR ADOCK 0500o423 Attachment Q
PDR cc:
T. T. Martin, Region i Administrator R D. Swetland, Senior Resident inspector, Millstone Unit Nos.1,2, and 3 V. L. Rooney, NRC Project Manager, Millstone Unit 3 f
4e
.h 4
4 ATTACHMENT A l
Table 1 - MILLSTONE 31995 ECT
SUMMARY
DESCRIPTION S/G 11 S/G D TOTAL
- Number of Tubes 5626 5626 22504 Number of Tubes inspected 4237 4236 8473 Tubes with Maximum Flaw > 40%
1 10 11 Tubes with Flaws > 20% but < 40%
11 29 40 Tubes Plugged as a Result of this inspection 1
10 11 Table 2 - LOCATION OF TUBES PLUGGED DURING RF05 l
ROW COLUMN S/G ROW COLUMN S/G 58 76 B
55 63 D
42 100 D
j 36 45 D
51 81 D
51 45 D
52 89 D
51 46 D
52 90 D
)
41 51 D
48 95 D
Table 3 - TOTAL TUBES PLUGGED TO DATE S/G A S/G H S/G C S/G D TOTAL Fabrication 1
2 2
0 5
l Preservice 2
1 1
1 5
RF01 1
0 0
1 2
RF02 4
0 4
RF03 0
5 5
RF04 6
1 0
7 RF05 1
10 11 Total 14 4
4 17 39
- All four Steam Generators s
I
.-