ML19329B852

LER 77-018/01T-0:on 771108,station Review Board Found Auxiliary Feed Pump Turbine Governor Valve Vibrational Closure Design Deficiency.Caused by Lack of Force to Hold Valve Open.Requests Design Mod for Pump Turbines

ML19329B852
Person / Time
Site:	Davis Besse
Issue date:	11/17/1977
From:	Beyer B TOLEDO EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19329B801	List: ML19329B800 ML19329B852
References
LER-77-018-01T, LER-77-18-1T, NUDOCS 8002060861
Download: ML19329B852 (2)

Text

- .-. - _ _ .~ . .. .

U. S. NUCLEAR RECULATORY CCMWSSION

.NI D *.1366 '

(7.)

LICENSEE EVENT REPORT CCNTR O'. GLOCX: ] I l l l l (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

L l0lH l D l B ] S l 1 l@l 010 l- LICENSE l 0 l0NUMUt:R lN lP lF l- l0 l253 l@l4 26 l1 l1 TYPE LICENSE l1 l1 40 l@l l

Si LAI $8 l@

i d fr LICENSEE CODE 14 15 COhl*T .

> l011I 5$,*c'

! L }@l 015 l 0 l- 101314 16 68

@l63 1 11 10 18 17 17 l@ll11ll171717 EVENT CATE 74 75 REPORT D AT E 80 l@

i 8 40 64 OOCKET !; UMBER EVENT DESCRIPTION AND PROSA8LE CONSEQUENCES h ITTTl l Cn November 8,1977, durinc a Station Review Board review of 30 dav non-eeriodic i ioIal l Report NP-33-77-80, it was determined a design deficiency existed. The Aux 111arv i I

l o 141 IF eed Pump Turbine 1-2 governor valve had vibrated closed from surging vibrations l o i s i I originating at the Startup Feed Pump motor. It was previously thought a cocmonent I g o !c ; l failure of the governor valve caused the closure, not a desian deficienev. The f l o 17 l l governor valve would vibrate closed in several hours of Startup Feed Pump ooeration. l i

l o , 3, i l(NP-32-77-18) JO CONIP. VA t.g E SYSTE?.1 CAUH CAUSE CODE CC ,5 $UECCDE CCVPCNENT CODE SUSCOCE SUSCCOE ioici Ic !H I@ Is j@ ] Al@ I z i zi z i z i z i z i@ Iz i@ Iz i@ 2J 7 8 9 13 11 12 IJ 'd Id OCCURRC:CE REPCRT REVISION

. SEQUENTIAL EV ENT YEAR RESORT NC. CODE TYPE No.

LER Ro

@ ,Ryg 17171 1-1 I O l li 81 Ld 10111 IT I L-J lol 2; 24 26 27 IS 23 30 31 32

_ 21 22 CNP T .T HCVR$ 22 S I 80 1 9. S PPLIE '.* ANL A ER K AC C jaaXlgl: F jg 4 l25z lg 'l:sz!g 2 l0l0l0j 4e l l Ylg 4i l2Nlg 4

lAlg 42 lTjll4l7lg 44 4r CAUSE DESORIPTION AND COPRE0!!VE .iCTIONS j 3 ) o ; lThe governor valve accarently closed because there is no force to hold it onen excest I i i ; , , gf riction in the linkage and valve packing. Facility Change Request 77-450 has been ,

,,,.,,  ; written which requests 2 dasign me.fification be incorporated on both Auniliary Feed 9 The modification is being investiga*.ed by  ;

,,,3,  ; Pump Turbines to preclude recurrence.

,,,,, gT erry Turbine.. the turbine vendor.

so j 7 s s

'T S

• , PC'.YE R OTHER STATUS 015 HY CISCOVERY DESCRIPTION g l B l@ l 0 l 3 l 0 l@l NA l l z l@j- NA [

A ftVtTY CC TENT LoCATICN CF RELEASE aELEASED 0, aELEASE AMOUNT OF ACTIVITY IiI6i dl Z l @ l ZI@)l NA l l NA da l

7 9

'w 11 44 45 PERSCWEL EhPCSLAES NLt.'1 E R NA i i l i I ? ! l 0 l 0 10 lhlTYPEZ '*

!hlDEICRIPTION "

PEascNsE't mLZEs

? Nu . n a cEsCR' Prion @ -

L lt jul10lJl0l@lNA "

l TCS,S ' C"a E

'/; "* @ g O$$ 06084/

l t b,i , >

l 2 l@l aNA ,a 8

ceg )k ONTt')N

!ll!!!'f!I I ' ! ;;

i C lN16] NA 8 .I > 10

-l t,e8 ts 9 DVR #152-1 Bernie Beyer ,,.,cN E:

419-259-5000, St. 223

,,, n , , n , y , , , ,

i .

[ T0u J EDISON COMPANY V} DAV7S-T, ESSE itNU ONE NUCLEAR POWER STATION SUPPLEMENTAL INFORMATION FOR LER NP-32-77-18 t

DATE OF EVENT: November 8,1977 FACILITY: Davis-Besse Unit 1 IDENTIFICATION OF OCCURRENCE: Auxiliary Feed Pump Turbine governor valve vibra-tional closure design deficiency.

Conditions Prior to Occurrence: The plant was in Mode 3, with Power (MWT) = 0 and Load (MWE) = 0.

Descriotion of Occurrence: On November 8, 1977, during a Station Review Board review of 30 day non-period i: report NP-33-77-80, it was determined a potential design deficiency existed. the Auxiliary Feed Purp Turbine 1-2 governor valve had vibrat>d closed from surgin;; vibrations originating at the Startup Feed Pump motor.

It was previously thought a component failure of the governor valve caused the closure, not a design deficiency; it was subsequently found that the governor valve would vibrate closed in sev tral hours of Startup Feed Pump operation.

/m\

\'N '/ Designation of Accarent Cause of Occurrence: The governor valve apparently closed because there is no force ta nold it open except friction in the linkage and valva packing. During operation of the motor dris an Startup Feed Pump, whien is located in the same room and creates a surging vibration, the governor valve linkage vibrates and the governor valve closes due to gravitational forces in the linkage.

Analysis of Occurrence: Thara is no danger to the health and safety of the public or to station personnel. The Auxiliary Feed Pump Turbine 1-2 governor valve posi-tion is be'ing verified every twenty minutes during Startup Feed Pump operation to verify the Auxiliary Feed Pumps will respond if required. Control Room indication is available for the open and closed valve positions of the Auxiliary Feed Pump Turbine governor valve.

Corrective Action: Facility Change Request 77-450 has been written which requests a design modification be incorporated on both Auxiliary Feed Pump Turbines to pre-clude recurrence. The modification is being investigated by Terry Turbine, the turbine vendor.

Failure Data: This is the second design deficiency discovered on the Auxiliary Feed Pu=p Turbines. The speed control failures were also due to a design deficiency.

]

v

- -,-w>%w- - --- y c- -