05000346/LER-1978-077-03, /03L-0:on 780710,component Cooling Water Pump Vibration Readings Exceeded Max Limits.Caused by Component Failure.Pump Bearings Found Failing.Bearing to Shell Clearance Increased & Pump Bearing Replaced

/03L-0:on 780710,component Cooling Water Pump Vibration Readings Exceeded Max Limits.Caused by Component Failure.Pump Bearings Found Failing.Bearing to Shell Clearance Increased & Pump Bearing Replaced

ML19326A113
Person / Time
Site:	Davis Besse
Issue date:	08/04/1978
From:	Hartigan J TOLEDO EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19326A105	List: 05000346/LER-1978-077, Forwards LER 78-077/03L-0 05000346/LER-1978-077-03, /03L-0:on 780710,component Cooling Water Pump Vibration Readings Exceeded Max Limits.Caused by Component Failure.Pump Bearings Found Failing.Bearing to Shell Clearance Increased & Pump Bearing Replaced
References
LER-78-077-03L, LER-78-77-3L, NUDOCS 8001310673
Download: ML19326A113 (2)

LER-1978-077, /03L-0:on 780710,component Cooling Water Pump Vibration Readings Exceeded Max Limits.Caused by Component Failure.Pump Bearings Found Failing.Bearing to Shell Clearance Increased & Pump Bearing Replaced

Event date:
Report date:
3461978077R03 - NRC Website

text

U.E. NUCLEAR REGULATORY COMt.itS5tv.d MRC FUM 366

' LICENSEE EVENT REPORT NTROL BLOCK: l l

l

}

]

1 lh (PLEASE PRINT OR TYPE ALL REQUIRED INF ORMATIONI e

i l Hl Dl B l S l 1l@l 0 } 01 -l 0 l 0 l N ] P l F l - l G j 3 ]@l 4 { 1 l 1 l 1 l 1 [@l l

l@

26 UCEre^5 TYPE 40 Si GAT 54 7

8 9 UCENSEE CODE le IS UCENSE NWSER 17l8l@

@] 0l 5 l 0] -l 0 l 3 l 4 l 6 @l 0 l 7 l 1 l 0 l 718 @l 018 l 014 CON'T lolti [RCE lL 74 75 REPCRT QATE do e3 69 EVENT GATE 60 61 COCK ET NuMgER I

3 EVENT DESCRIPTION AND PROS A8LE CONSECUENCES h l

l__o i 21 l On July 10, 1978 during the conduct of surveillan2e testing, Component Cooling W

.1 mil.

j I o 121 1 (CCW) Pump 1-1 vibration readings exceeded the allowable 1.5 mils. max by The l

l There was no danger to the health and safety of the public or unit personnel.

ro g l The standby CCW Pump was placed in l j unit was in Mode 5 at the ti=e of the occurrence.

o;3)

(NP-33-78-92) l UTs-] I service prior to the failure of CCW Pu=p 1-1.

I 10!71 1 l

lotalI Couw.

vatvf sYsTtu

CausE

CAusE CCCE CCOE

$U8C00E COMPCNENT CODE SusCCDE SueCODE IW lB l@ $@ U@ l P l Ul Ml P lIlIlh l3 j@ { @

1o691 7

8 9

10 11 12 13 13 19 20 RCVISicN OCCURRENCE REPCRT SEQUENTIAL

, ENT YEAR REPCRT NO.

CCCE TYPE NO.

r7@,a=

17 18 I l-1 1017171 W

1o131 M

l-l Lil EV (E R rmo t

)

_.2i 22

2 24 u

s 22 20 si 22 D 'fal E" 'fCP/c"A cEP7 fit

'TT?$""

wouas @ ^E E*S E PCE"$$a. ""s5tfE7 Ma8v"OCERER l^ l@LI_J@

I z l@

I z!@

10 10 10 lo i I Yl@

lYl@

IAl@

IcI2lolo[@

o JJ 34 JS 36 3I 40 48 42 43 A4 47 CAUSE DESCRIPTION AND CCRRECTIVE ACTIONS failure. The oumo bearines were examined I

l ;oj] The caus,e of this occurrence is component and the thrust bearing was found to be failine. Further investization revealed tha I

,jij l ioint was not s=co th. _

liearing to shell clearance was not adequate and the bearing

,,,,,I l

,,,j,l Maintenance personnel increased the bearing to shell clearance, smooched the bearine I

joints, and replaced the pu=p bearing.

,,,,, i l so 7

a s

$A

%ACVvER OTHER STATUS Ot RY OlSCCVERY DESCRIPTICN.

5074.01 l

NA l

L3J@lSurveillanceTestST l

l } 5 l l G ]@ l 0l 0 ] 0 l@l so 44 as as LOCATION or REtsasE @

i2 n

5' a$tiviTv Co'OTENT AuCuNTop 4CriveTv @ l '

I i

r.ELEasto op RELEASE l NA l1 le l W @ y@l NA 30 44 45 7

8 9 to 1

PER$CNNEL EMtsuRE5 NUMSER TYPE DESCRIPTiCN I

li l 71 1 01 al 01@l z l@l NA PER$CNNEL INJu IES NUM8ER l

[ - ] I 0 l a 10 l@QESCRIPTION l NA 80 9

11 f2 t

s

\\# LCSS CP CR CAMACE TO PAC:UTV 7-l R O O1 R10 TYPE DESCRIPT1CN L'_LSJ l ZI@l NA 30 7

8 9 1Q

,$3CEO CE CRIPTICN i

iiiiiiiiiiii!:

n oi i x18i NA 68 69 30 ;

b20.he 30 {

Tnhn Hartiean PwcNE:

3 TOLEDO EDISON COMPANY p)

DAVIS-BESSE UNIT ONE NUCLEAR POWER STATION (v

SUPPLDfENTAL INFORMATION FOR LER NP-33-78-92 4

DATE OF EVENT: July 10, 1978

' FACILITY: Davis-Besse Unit 1 IDENTIFICATION OF OCCURRENCE: Component Cooling Water Pump 1-1 high vibration Conditions Prior to Occurrence: On July 10, 1978, at 1400 hours0.0162 days <br />0.389 hours <br />0.00231 weeks <br />5.327e-4 months <br /> during the con-duct of ST 5074.01, " Component Cooling Water (CCW) Monthly Surveillance Test",

CCW Pump 1-1 vibration readings exceeded the allowable 1.5 mils max by.1 mil.

CCW Pump 1-1 was shutdown and standby CCW Pump 1-3 was placed in operation. CCW Pump 1-2 was also in operation at the time of the occurrence.

Since the unit was in Mode 5 at the time of the occurrence, the unit was not placed into an action statement. This incident is being reported as documentation of a compon-eut failure.

Designation of Aeoarent Cause of Occurrence: The cause of this occurrence is component failure. Under Maintenance Wo-k order 78-1839, the pump bearings w were examined and the thrust bearing was found to be failing. A thorough inspec-

) tion of the pumn was performed and it was discovered the bearing to shell clear-d ance was not adequate and the bearing joint was not smooth. This may have re-stricted oil flow and caused the bearing failure.

Analysis of Occurrence: There was no danger to the health and safety of the public or to unit personnel. The unit was in Mode 5 at the time of the occurrence. The standby CCW Pump was placed in service prior to the failure of CCW Pump 1-1.

Corrective Action

Under Work Order 78-1839, maintenance personnel increased the bearing to shell clearance, smoothed the bearing joint, and replaced the thrust bearing on CCW Pump 1-1.

The other two CCW Pumps will be inspected when removed from service for normal preventative maintenance.

Failure Data: There have been no previous reported occurrences of CCW Pump bearing failures.

LER J78-077 J