05000336/LER-1980-027-03, /03L-0:on 800729,during Steady State Power Operation,Leak from Failed Socket Weld Found on Fitting in 1-inch Safety Injection Tank Recirculation Line.Caused by Crack Due to long-term Fatigue Attributed to Vibration

/03L-0:on 800729,during Steady State Power Operation,Leak from Failed Socket Weld Found on Fitting in 1-inch Safety Injection Tank Recirculation Line.Caused by Crack Due to long-term Fatigue Attributed to Vibration

ML19344E575
Person / Time
Site:	Millstone
Issue date:	08/25/1980
From:	Harris J NORTHEAST NUCLEAR ENERGY CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19344E574	List: 05000336/LER-1980-027, Forwards LER 80-027/03L-0 05000336/LER-1980-027-03, /03L-0:on 800729,during Steady State Power Operation,Leak from Failed Socket Weld Found on Fitting in 1-inch Safety Injection Tank Recirculation Line.Caused by Crack Due to long-term Fatigue Attributed to Vibration
References
LER-80-027-03L, LER-80-27-3L, NUDOCS 8009020285
Download: ML19344E575 (2)

LER-1980-027, /03L-0:on 800729,during Steady State Power Operation,Leak from Failed Socket Weld Found on Fitting in 1-inch Safety Injection Tank Recirculation Line.Caused by Crack Due to long-term Fatigue Attributed to Vibration

Event date:
Report date:
3361980027R03 - NRC Website

text

l NHC>QRf.1366%

U. S. NUCLE AR ret.,ULATORY COMMISSION 7 77)

LICENSEE EVENT REPORT

(,)

CONTROL BLOCK: l l

l l

l l

l (PLE ASE PRINT OR TYPE ALL REQUIREO IN*ORMATIONI 1

6 o lij l Cl Tl M l N l S i 2 l@l 0l 0l -l C l 0l 0] 0 l - l 0 l 0 l 0 ]@l 4l 1l 1l 1l 1[@l l

lg i

8 9 LICENSEE CCDE 14 15 LICENSE NuYSER 25 26 LICENSE TYPE 40 SF CAT 58 CCN'T T,y l L @l 0 l 5 l 0 l 0 l0 l3 l3 16 }@l 0 l 7 l C l 9 l 8 l 0 l@l 018l 2l 5 l 8 l 0 l@

olil F

8 60 61 DOCKET NUM9ER tia 69 Evt1T DATE 74 75 REpoR f QATE 80 EVENT DESCRIPTION AND PROB ABLE CONSEQUENCES h l o l 21 l During steady state power operation, a leak was evident within the containment. A l "

lo t a l I containment entry disclosed a failed socket weld on a fitting in a 1 inch safety i

I o !41 l injection tank recirculation line. The leak was isolated and the weld was ground out l

l o 13 l l and rewelded.

Similar events

77-10 (3/21/77); 77-37 (9/17/77)

[

1 lo is i l 1o171 1 I

l l 0 l8 l l 30 7

8 9 DE CCCE SLBC E CCMPCNENT CODE SL B CO O'E S

E l0l9l l Cl Bl@ lE l@ l Xl@ lP lIlP lE lX lX l@ W@ lZ l@

7 8

9 10 11 12 i3 18 19 20 SEQU ENTI AL OCCURRENCE REPORT REvlSION LE R. RO EVENTvEAR rdPCRT NO.

CODE TYPE N C.

OyaEg l218 l0 l l-l l0l2l7l l/l l 0l 3 l lL l l_l l 0l 22 23 24 26 27 28 29 30 31 32 T KEN AC C ONP NT M T HOURS 22 58 i PC E.

SUPPLiE MANLP CTURER lBl@lXI@

IZl@

l Zl@

1010101 l

[J. _j @

l Y l@

lN]@

lBl1l310l@

n 25 2.

2r 0

n 4,

u CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h 1i i o l l The cause of the leak was a crack caused by long term fatigue attributed to vibration.

l ii iii i The long term corrective action for this recirculation line will be a stress I

l evaluation and hanger rework (if reauired) during the refueling outage.

I i,i2i I

lii al I I

it 14i l

1. 'cglJ7

% PCWER OTHE R STATUS dis RY QlSCOVERY CESCRIPTION sTA Ii l51 d@ l 1 l 0 l 0 l@l NA l

lAl@l Ooerator observation l

'2TiviTY Cc'OrtNT AuovNT cr ACriviTv @ l toc 2 Tion oP RELEASE @

4 l i l 6 l l Zl @o cP aELEASE[_Z_jgl aELEASE NA l

NA l

PER$cNNEt ExPcSEEES oESCRiPrioN@

NuveEn TvPe 1010lOl@lZl@l NA l

2 7 PERSONNEL INJV IES NUveER OESCR PTION li js t I 01 01 01 @ l NA l

80 7

8 9 11 12

" '" ^ o'N '''@

' 'S ESCR *T T PE li 191 l Zl@l NA l

30 7

8 9 to

'SSUED QE CRl* TION

o N 44 NA l

LIIIIIIIIII'I 4,00 85 on t,1,1, 7,7 7ql o

7 i

ATTACHMENT LER 80-27/3L-0 Millstone Unit 2 Docket No. 50-336 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES During steady state power operation, a leak was evident within the containment due to the frequency of pumping the contaiment sump and a slow decrease in Safety Injection Tank (SIT) Number 1 level. A containment entry disclosed a failed socket weld on a fitting in a 1 inch recirculation line. The leak was isolated and the weld was ground out and rewelded.

Similar events

77-10 dated 3/21/77; 77-37 dated 9/16/77 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS The cause of the leak was a crack caused by long term fatigue attributed to vibration. The leak path was via SIT Number 1 through s'

a leaking drain valve 2-SI-618 caused by a controller malfunction.

The fuses to 2-SI-618 were pulled to fail the valve closed. The valve is a Fisher Type 667-DBQ 1 inch diaphragm control valve rated 1500 PSI. The valve controller will be repaired during the refueling outage.

The long tenn corrective action for the recirculation line cracking will be a stress evaluation of this line and hanger rework (if required) during the refueling outage.

The piping is Schedule 40S, Type 304 Stainless Steel,' ASME Class 2.