ML20093L842

Special Rept SR-95-002-00 on 951011,ABB C-E Identified Leaking Plug Due to build-up of Boric Acided Crystals Around OD of Plug.Leaking Plug Removed by Tig Relaxation & Replaced/Another Rolled Mechanical Plug

ML20093L842
Person / Time
Site:	Waterford
Issue date:	10/23/1995
From:	Keuter D ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
SR-95-002-00, SR-95-2, W3F1-95-0174, W3F1-95-174, NUDOCS 9510260091
Download: ML20093L842 (4)

Text

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D. R. Keuter General Manager Plant Operations 'I Y3Y1-9b-0174 A4.05 PR October 23, 1995 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555

Subject:

Waterford 3 SES Docket No. 50-382 License No. NPF-38 Reporting of Special Report Gentlemen:

Attached is Special Report Number SR-95-002-00 for Waterford Steam Electric Station Unit 3. This Special Report is submitted per 10CFR50.36(c)(2) and Technical Specifications 4.4.4.5.a and 6.9.2.

Very truly yours,

% \ ,

. 1J Q D.R. Keuter General Manager Plant Operations DRK/DFL/tjs Attachment .

cc: L.J. Callan, NRC Region IV C.P. Patel, NRC-NRR G.L. Florreich J.T. Wheelock - INP0 Records Center R.B. McGehee N.S. Reynolds NRC Resident Inspectors Office Administrator - LRPD 9.600bb 9510260091 951o23

/ l PDR ADDCK 05000382

-S PDR

SPECIAL REPORT j SR-95-002-00 Steam Generator Eddy Current Examination j (7th Refueling) '

On October 11, 1995, Waterford 3 completed a 20% inservice eddy current bobbin coil full length examination of each Steam Generator (S/G) and .1 100% hot leg top of the tubesheet. This report is submitted in '

l accordance with Technical Specification (TS) 4.4.4.5.a, which requires reporting the number of tubes plugged in each S/G within 15 days of completing Inservice Inspection (ISI) of S/G tubes pursuant to TS 6.9.2.

A follow-up report will be submitted in accordance with TS 4.4.4.5.b by October 11, 1996.

The total number of tubes which have been plugged in each S/G are shown {'

below:

1 S/G #1 S/G #2 Manufacturina/Preservice 6 20 Batwina (Preventive Pluaaina) 149 149 l

First Refueling 0 -

1 Second Refuelina 3 0 1

Third Refuelina 10 9 Fourth Refuelina

- Preventive Plugging as a result 4 5 of ECT

- Batwing Preventive Plugging 156 156 l 1

Fifth Refuelina 4 5 i

i 1

- ~ . . .

-SPECIAL REPORT  !

SR-95-002-00 Steam Generator Eddy Current Examination  :

(7th Refueling) 4 S/G #1 S/G#2 Sixth Refuelina

. Preventive Plugging as a result 1 2 of ECT

- 40% Thru-Wall Indications 2 0 Seventh Refuelina

. Preventive Plugging as a result 6 3 of ECT

- > 40% thru-wall indications 2 0

- Single circumferential indications 6 1

- S/G #1 cold leg leaking plug replaced *

{

t The total number of tubes which have been plugged in each S/G:

S/G #1 S/Gil Total: 349 351

• S/G #1 cold leg Row 41, Line 89 removed and replaced with a ABB-CE rolled' mechanical plug. ABB-CE identified the leaking plug due to the build-up of boric acid crystals around the OD of the plug. The CE leaking rolled mechanical plug was installed as a preventive measure August 1985 prior to commercial operation. The ABB-CE rolling process was suspect shortly after installation which caused Waterford 3 to re-roll 149 CE plugs per channel head in each S/G (12/86).

As evident by boric acid build-up, the ABB-CE leaking plug was removed by TIG relaxation and replaced with another rolled mechanical plug.

CR-95-0895 was written on October 3,1995 to evaluate root cause of plug failure.

2 E . .

i SPECIAL REPORT l SR-95-002-00 4

I Steam Generator Eddy Current Examination (7th Refueling) l t

j In compliance with Waterford 3's response to Generic Letter 95-03, Waterford 3 utilized the "Plus Point" coil probe to identify a total of seven hot leg top of'the tubesheet small (</= 20% thru-wall, OD

' initiated) single circumferential indications. The results of completing a 100% hot leg top of the tubesheet plus point coil

inspection of both S/Gs has identified the following indications:

Sinale Circumferential Indications S/G #1 S/G #2 4

6 1 i

t i.

4 b

1 3

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