ML18024B179

RO 50-296/79-19:on 791204,during Augmented Ultrasonic Insp of Core Spray Piping,Indication Located Adjacent to safe-end to Core Spray Pipe Weld.Caused by Stress Corrosion Cracking.Piping Replaced W/Carbon Steel

ML18024B179
Person / Time
Site:	Browns Ferry
Issue date:	12/05/1979
From:	Abercrombie H TENNESSEE VALLEY AUTHORITY
To:
References
NUDOCS 7912190554
Download: ML18024B179 (4)

Text

REGULAT INFORMATION DISTRIBUTION STER (ADIOS) .

ACCESSION NBR:7912190554 DOC.DATE: 79/ 12/05 NOTARIZEDa. NO DOCKET FACIL:50 259 drowns Ferry i~luclear Power Stations Unit 1r Tennessee 05000259 50=2o0~owns Pet ry Nuclear Power Station< Unit 2i Tennessee 05000260 50 299r'owns Ferry Nuclear Power Stations Unit 3i Tennessee 0500029o A ~

~ cs r4 AU HUH AFF IL I A T ION T

AbE <CHONUIE~H, Tennessee Valley 4uthor ity RECIP,NA~E RECIPIENT AFFILIATION I

SUBJECT:

RO 50 296/79-19:on 791204iduring auqmented ul trasonic insp of units 3 core spray piping<indication located adjacent to safe end to core spray pipe weld.Caused oy stress corrosion cracxing.Piping replaced w/carbon steel.

orsr~rsvrros coos: .aaars covrzs I'I1Lk.: Ltfc. (Uackf i t) r scsrvso:era / soccer srzs:~

NOTES:

REC IP IEN l COPIES HEC IP IEN T COPIES ID CODE/NAKE LTl'R ENCL Iu CODt/NAi~E LTTh ENCL INTEHNALa 0 R G FrlE 1 ~

02 hHC PDR 1 04 I 2 HPA 1 NSIC 1 H IRELAND 1 S HANAUEH 1 txTERNAL: 03 LPDR TOTAL NUh]HER OF COPIES RE4UIRtD: L TTR 9 E!')CL gag

3XLECOPY 'K) RRC 12/5/79

'.',=,:;jRC RFCI'

-! ANTP.. ".-'.-

l.'-..8, Huc1ear Regulatory Coamission Reg,ion 4X 101 Nazietta Street ~g gpss 5 AIf; 00 i P. O'RBLLY.

Suk.te 3100 Atlanta, Georgia 30303 'C. M. UPRIGHl' 0 CHENDLMj lV. S. RENTAL, F. J. LONG E, Q. E. MURPHY AFRO-50-296/>919 ,9. T. SUTHERLAND P

K M.C RK Reported under Technical Specification 6.7.2.a(9)

Date of Occurrence; 12/4/79 Speci.frication Time of Occurrence: 9:30 a,m. Unit 3

'reehnical involved: Hone Conditions Prior to Occurrence: Unit. 3 in refueling mutate. Vases 1 and 2 in normal operation at 995 MVe and 735 Yde, respectkvelr.

58entffication and Deacr'i tioa 6f. Occurrence: QiHe perfomfr;g an 'augmented uLtrasonic inspection of unit 3 coze spray piping, sn bd%cat5on was locet~

ad3scent to the safe-end to core sprsy pipe ~~M (weld Ho. DC&-3-l8) ~

fnspection was performed et>en though chks piping var being rap~sc:ed during the exfsting. scheduled outage. There veze no resulting significant occur" fences, no previous similar events, and no danger to the health or safeL)'f

'the pub1ic.

A grant Cause of Occurrence. Subseouent metallurgica1 analysis of the removed ultrasonic indication area revealed stress-corrosion cracking. in the weld heat-affected'cone ek gabe %0-inc> diameter, scb Gute 80, P-~>

less-stee1 pipei A detai1ed metaLLurgical report, is forthcoTair~

Qtbez Related Events: %e potent%ax foz stress-cozz.Agon cracking, in certai>

stain ess-steeK P.ping, his been previousl) ibex'iie5 Cenectt.ve Action T'eken nr Planned; Piping oa unit 3 was chansed out and replaced with carbon steel, L>nit 2 core spray piping vas chST'.ged to c-rhnn itee1 on a previous outage. LTnit X zefueliag. outage begins DanuaTy iK2, indi- LSM, at >+feb time we will perform an insenCce inspection to deterTnine cations ex%st. If indications are observed,. eweKuatMa and sobseqeent repafra aa necessa~ &El be performed.

r <

8 i.. AberczoTUbie Tosser 'Plant Superintendent

%res Vert'y Huclear PLaat P 001

'18190 QS$ g/g

T