ML20055D709

Forwards Steam Generator Tube Plugging Rept,Per Inservice Insp

ML20055D709
Person / Time
Site:	Trojan File:Portland General Electric icon.png
Issue date:	06/26/1990
From:	Walt T PORTLAND GENERAL ELECTRIC CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9007090319
Download: ML20055D709 (2)

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June 26, 1990 Trojan Nuclear Plant Docket 50-344 License NPF-1 U.S. Nuclear Regulatory Commission' Attn: Document Control Desk Washington-DC -20555

Dear Sirs:

Steam Generator Tube PluRKint Report During the 1990 refueling outage. an inservice inspection was conducted of all inservice tubes and several previously plugged tubes in-the four steam generators.

In accordance witn Technical Specification 4.4.5.5, " Steam Generators, Reports", attached is a desetiption of the number.of tubes-plugged or sleeved in each steam generator.

Sincerely, T. D. Walt Acting Vice President, Nuclear Attachment c:

Mr. John B.- Martin Regional Administrator, Region V U.S. Nuclear Regulatory Coannission Mr. David Stewart-Smith State of Oregon Department of Energy Mr. R. C. Barr NRC Resident Inspector Trojan Nuclear Plant 9007090319 900$2g ry

{DR ADOCK 05000344 PDC

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121 S VJ nmon Street, o tland Or@n 97204 '

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.' -Tr3jtn Nucl$1r Plant-Document Ctntrol Desk Occket 50-344.

June 26, 1990 9-LLicense NPF Attachment Page 1 of 1 i

I STgAN GgNgRATOR TUBS PLUGCING DuringL the 1990 refueling outage, an inservice ' inspection was conducted of all:1nservice tubes andfseveral previously plugged tubes in the,four-l steam generators. 'The inservice tubes and previously-plugged tubes which were returned to service by sleeving were' examined by oddy current. bobbin coil through;the hot-leg: side to'the cold-leg seventh tube' support.-

Indications from the bobbin coil examination were confirmed with a -

' motorized' rotating pan' cake. coil (NRPC). Additionally. an'NRPC exami-

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nation was performed on ki1L inservice steam generator tubes at the.

hot-lag upper tubesheet region, f The inservice inspection resulted' in, the plugging of an additional ~147 tubes,with Babcock and'Wilcoxl(B&W) steam f

generator tube Alloy 690 rolled: plugs.-

. Per a vendor recommendation.all'B&W steam generator tube Alloy 600-t rolled plugs of Heat Number 2848-2 were removed.from the hot legs.of the:

steam generators.. Plugs were removed from 17Ltubes.

B&W steam generator.

l tube A11oy' 690 rolled ' plugs were reinstalled'in 15 of' tho' tubes. - B&W-steam generator tube Alloy 690-sleeves were. reinstalled in 2 of the-tubes.

A' tube sheet sleeve andLone tube support sleeve were installed'in-I the hot-les side of each of the sierfed tubes.

As a precautionary measure in t>

hot legs of[the A andTD steam gener-1 f

l ators _ remain!.ng Westinghouse m' nanical plugs, beyond those which were:

identified ir Nuclear Regulatory Commission Bulletin 89-01',. " Failure of Westinghouse Steam Generator Tube Mechanical Plugs",;had plugiretaining.

. devices inst alled.

The followin:t.t able lists: the number of tubes inspected. plugged. and =

sleeved in each steam generator.

-I Steam Generator 1

A B

"C-

'D No. of Tubes Inspected in 1990 3252 3243 3186-13170 No. of Tubes Plugged in:1990:

• For Axial Cracking 23-9.

58 55

• For Circumferential Cracking 1

-0 0

El

• Total 24 9

58-56 No.gof Tubes Sleeved in 1990 0

0 2*

0

.ia No. of Tubes / Plugged Total 165.

154:

260 283

• These' tubes were previously plugged.

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