ML19317F356

Incident Rept, Corrosion Investigation of Unit 2 Tendons. on 731016,tendons Mark 31H31,31H32,31H33 & 31H34 Found Not Greased on Unit 2 Reactor Bldg.Insp Procedure Prepared. Excessive Corrosion Not Expected

ML19317F356
Person / Time
Site:	Oconee
Issue date:	11/12/1973
From:	DUKE POWER CO.
To:
Shared Package
ML19317F353	List: ML19317F352 ML19317F356
References
NUDOCS 8001140610
Download: ML19317F356 (3)

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DUKE POWER COMPA!1Y OC0tlEE flUCLEAR STATION lilCIDENT REPORT CORROS10fl lilVESTIGATION OF UNIT 2 TEND 0!1S NOVEMBER 12, 1973 r

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. DUl;E POWER COMPAllY W -0C0 flee flVCLEAa STATION lilCIDEtif REPORT CORROSI0tt INVESTli."\ TION Ol' UNIT ~ 2 TEN 00tlS NOVEMBER 12~, 1973 q l.0: :Introdection

-At approxim tely?ll':3'0a.m. on_0ctober 16, 1973, it was discovered that four

tendo'ns; mark -31 H31, 31 H32, 31 H33, and 31H34 had not been greased on Uni t. 2

' Reactor Buliding. ;The ungreased. tendons.wcre discovered during an inspection

'for. leaking grease;cdps.

"Mr.lljanff Jape. of LAEC', Directorate of Regulatory Operations, was .notifled-that-the above_ tendons had not been-frcased. Also, Messrs. J. E. Smith, S.1b. 2 Hager, T. H. McDaniel , D. L. Freeze, D. G. Beam, R. L. Di ck, and W.-S'. Lee we're notified.

0n'Octoberil'6,;1973, Unit 2 was in the pre-operational test phase with fuel loaded. Zero power physics i.esting had not started. ,

Scquence of-Eve'nts

- 2.0 See Attachment A

30. . Evaluation-

- Design Engineering advised.that excessive corrosion was not expected since

tl.a tendonsLwere coated with-NO-0X-10 500 prior to installation. Since the itime' interval betWeen tendon installation and discovering the ungreased

. tendons was approximately two years,:the_ tendons should be inspected prior to' greasing. Pesign Engineering would provide an inspection procedure s

(At.tachmen t : B) .

Since-excessive corrosion was not expected, the Reactor

Building was 1 structurally sound. Unit 2 was in the pre-operational test phase and no other structures or systems'were affected by_the ungreased tendons.

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4.0) Corrective'Actlori The ; Construction Department. developcd _ and approved. procedure .183 (At tachment . C)

from Design. Engineering's procedure for inspecting the,ungreased tendons.

InD. addition,' procedure 187. (Attachment 'D)' was developed and approved to verify

that the1 remaining Unit.2' Reactor':BuildingLtendons were greased.

'LTendons . 31 H31,. 31 H32, and 31 H33 were inspected in accordance eith procedure .

il83'and'foun_d,to be satisfactory. The; inspection. sheets are enclosed in J

At ta c hmen t; E.'

~ ' Based.upon(the satisfact'ory condition'of the above tendons and physical

$1nterferencesLthe inspection procedfure (183) was( revised prior to -inspecting-

? tendon; 31H34; LThefproposed; revision was reviewed by Design- Engineering 'and .

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Tendon 31111h spc. Inspected in accordance ui th procedure 133, revision 1, dated 10-24-7j, and found to lie sat li.f ac t ory.

Tendens 31!!31, 31!G.', 311133, and 31113 f vere retensienci anil/or grear.cd. /11 acc.cssihic tendons in linit 2 Reactor Duilding uere inspected in accordance with psocedure 137 and found to i.e greased.

50 Verification The insp:etion of the four ungreased tendons indicated there uns not any corr _osina. da.nage as the resul t of not applying perranent grease protection.

The ten hs ucre restrest.ed to comparabic ar.-found 1if tof f values and

-great.ed, thereby returning the building to its designed criterion.

All at.cessibin tendrant, in Uni t Beactor Coll <!ing uere found to be greased.

6.0 Safety,/ gal,yp ,

f Recurrence has beco climinated by the inspection of all accessible tinit 2 tendons in accordain.;c with procedure 137 70 .E. nclosu- r- e- -s Attachuent A Log Sheets Ai i .u .i .-o . T. i...%iepi i s.qi ne:o r i ns.. Proc. dure '

/,ttachecnt C Construction Procedure 133 Attachment D Construction Procedure l'17 Attachnent E Inspection and Prestress Docuracntation Attachnent T Greasing Documcr tation Attachment L Tendon filling Docunentalion At t ac! bent 11 Pressure Gage C..libration Sheets Attach acnt l' Grease DocuiaantnLion i ,

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