ML20154D347
| ML20154D347 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 09/08/1988 |
| From: | Fay C WISCONSIN ELECTRIC POWER CO. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| CON-NRC-88-084 VPNPD-88-455, NUDOCS 8809150252 | |
| Download: ML20154D347 (2) | |
Text
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Wisconsin Electnc POWCil COMPANY au w M.cnon pow ruun.osee.w n201 (414)221 2345 VPNPD 455 NRC-8 8- 08 4 September 8, 1988 U. S. NUCLEAR REGULATORY COMMISSION Document Centrol Desk Mail Stop Pl-137 Washington, D.C.
20555 Gentlemen:
DOCKET 50-301 SLEEVING REPAIR OF STEAM GENERATORS POINT BEACH NUCLEAR PLANT, IJNIT 2 The purpose of this letter is to in'orm the U. S.
Nuclcar Regulatory Commission of our plans to repai; a limited number of Point Bcach Nuclear Plant Unit 2 steam generator tubes by sleeving during the scheduled Fall 1988 refuelitig outage.
The Unit 2 outage is scheduled to begin October 7, 1988, and last through November 16, 1988.
We expect that the scope of the planned sleeving project can be accomplished without extending thic outage.
In order to maintain the maximum number of tubes in service and thus prolong the life of the Unit 2 steam generators, Wisconsin F.loctric, licensee for the Point Beach Nuclear Plant, is planning to selectively install mechanical sleeves in tubes in the Unit 2 steam generators in accordance with Technical Specification 15.4.2.A.6.
Selection of tubes to be sleeved will be based on eddy current testing (ECT) prior to sleeving.
As part of the ongoing maintenance and inspection programs at Point j
Beach N'aclear Plant, ECT has been performed on the Unit 2 steam generatore during past outages.
ResOlts from recent inspections, conducted during tre Fall 1987 outago, and prior annual outages indicate a significant number of Unit 2 steam generator tubes with tube wall degradation less than the plugging limit as defined in Technical Specification 15.4.2.A.5(a).
The majority of the l
degradation is in the B stean generator cold leg where tube thinning was detected in prior years.
The number of tubes in the cold leg aection cf the A steam generator requiring repair is projected to be small.
It is presently expected that approximately 175 sleeves can be installed in each steam generator cold leg during this year's I
outage.
However, depending upon the results of the pre-sleeving ECT or sleeve instatlation rate, there is the possibility that more than 350 sleeves may be. installed.
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,. Document Control Desk September 8, 1988 Page 2 i
i Point Beach Nuclear Plant sleeving repair was authorized by the Nuclear Regulatory Commission by Amendment Nos. 71 and 76 to Facility Operating License Nos. DPR-24 and DPR-27.
In 1983, eleeving was performed on both Unit 2 steam generators.
The 1983 project was a preventive program to address the onset of tubesheet crevice defects.
Approximately 1500 tubes in the central region of the hot leg side in each Unit 2 steam generator were sleeved.
Westinghouse Electric Corporation performed this sleeving project in accordance with the sleeve design, process description, and analysis as reported in WCAP-9960, "Point Beach Steam Generator Sleeving i
Report," Revision 1, February 1902 (Prvprietary).
Limited scope sleeving was performed in the B steam generator during j
the Fall 1987 outage.
This sleeving scope was performed by l
Westinghouse Electric Corporation consistent with WCAP-9960 and our
]
revised analysis as reported in WCAP-ll573, "Point Beach Unit 2 j
Steam Generator Sleeving Report," September 1987 (Proprietary).
The l
1987 program was described in our August 17, 1987 ' submittal.
1 The 1988 sleeving program planned for this fall wtll be consistent with our 1987 sleeving program with two exceptions.
I l
1.
The sleeve length will be 30" in lieu of the 36" length sleeves
(
i used in the past.
The shorter sleeve provides greater l
i l
peripheral coverage in the steam generator while still allowing l
sufficient vertical coverage to e.dequately span degraded areas.
l The analysis of 20" sleeves is discussed in WCAP-11573.
2.
Advanced robotic tooling (ROSA), developed by Westinghouse and used successfully in sleeving prograns at other plants, will be l
used for the 1988 program.
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Please contact us if you have any questions in regards to our steam generator tube sleeving plans.
[
Very truly yours,
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Fy (
C. W.
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Vice President l
Nuclear Power
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l Copies to NRC Region.d Administrator, Region III l
l NRC Residm.; Inspector
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