ML20052F400
| ML20052F400 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 05/05/1982 |
| From: | Barrett L, Conte R, Young S Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| PNO-TMI-82-011, PNO-TMI-82-11, NUDOCS 8205120423 | |
| Download: ML20052F400 (1) | |
Text
50289-811121 May 5, 1982
- ;. E.. "l :J:.Y h0TIFICATIC" 0F EVENT 0:. Uh 5UAL OCCUR.ENCE--FNO-TMI-82-011
-is prelirir.ary notification constitutes EARLY notice of events of POSSIBLE safety or
- 311; in erest significance.
The information is as initially received without verifi-cation or e' valuation and is basically all that is known by NRC staff on t Ate g
Licensee Emeroency Classi i' tigni,;$
Fa cili ty : GPU Nuclear Corporation p
c Three Mile Island, Unit 1
.,X Not Applicable g
%(.
Docket. No. 50-289 j/
[
S" 6
Subject:
ONCE THROUGH STEAM GENERATOR TUBE DEGRADATION The licensee ' decided to reseal virtually all of the'31,000 tubes in both 0 "
N Q
Through Steam Generators.
The additional. work will'be performed because g
further testing hasfindicated that defects were found with special _ test instrum sN specifically designed and developed for examining the very ends of tubes.
Not all.31,000 tubes show indications of damage at the top, but the licensee feels it will be more efficient to reseal most of them, whether or not defects were indicated in the tests.
A total of 500 to 700 tubes in the two generators are likely to be plugged and taken out of service.
The repair niethod involves the use of controlled explosive charges to expand the tubes.
The licnesee reports that the technique was previously used both in newly constructed he'at exchangers and tube re' pairs in the utility industry (since late 1960's).
The length of the tubes to be expanded will be the upper 10 inches of the tube in the upper tube sheet area wh.ich will extend several inches below the area affected by corrosion.
The licensee reports that this decision is not expected to have a substantial impact on the original $25 million cost estimate for repair of the.TMI-l steain generators.
The tube repairs are not expected to begin until mid-summer, after their application.
to the TMI-l steam generators has been thoroughly tested and qualified for use.
Media interest occurred' because the licensee issued a press-release.
NRC does not.
, lan a press release. -The Commonwealth of Pennsylvania was informed.
p This preliminary notification is issued for information only and the 'NRC plans to
' continue monitoring events as, they occur.
NRC site staff received notificatiori of this occurrence from the licensee Communications Division at 4:30 PM, May 4,1982, and this information was current as o 9: 0 'AM -
A [ r t p E.,. d r W CMD r/d h b"
May 5* 1982 Contact :
S. Young 590-1155 Conte 590-1125 L. Barrett 590-1120 Distribution:
H. St. /4 ff3 MNBB // 01 Phillips 8?B(/ E/W //_g Willste //?/o Air Rights #W Chairman Palladino EDO NRR IE NMSS ST Comm. Gilinsky PA OIA RES B. Snyder l
Comm. Ahearne
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J. Tourtellotte 8205120423 820505 E M 011 c.mn.as&crzioM?4
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