ML20129D619

Rev 1 to Action Plan 27, Auxiliary Feed Pump Main Steam Inlet Isolation Valve (MS-106) Problem Analysis

ML20129D619
Person / Time
Site:	Davis Besse
Issue date:	06/26/1985
From:	Bonner N TOLEDO EDISON CO.
To:
References
NUDOCS 8507300112
Download: ML20129D619 (10)

Text

. - -- .. . .-. . . - . . . =.- . . . .-.

f* r/ I s

O

~

w o v n w'n L1

. e , ,i t , . , .

f si t; u bc l'":% a a a m a s u u i. G a 1

\L; y$ g . by i

3 i

ACTION PLAN # 27

. TITLE: AUXILIARY FEED PUMP TURBINE MAIN STEAM INLET I

ISOLATION VALVE (MS-106) PROBLEM ANALYSIS i

i i

O -

APPR.

CHAIRMAN FOR REV DATE REASON FOR REVISION BY TASK FORCE IMPL.

0 6/25/85 Initial Issue See Rev. O. for approvals Revised Report Text and Added Action 1 7/3/85 Plan Steps j [g V

i 4

O 8507300112 850626 PDR ADOCK 05000346 P PDR g- -.-- r---- .eerrg- --m-wyw -w ey,ey w. - ,y -y++%$ e /y= --9+m

1 I

i , ,

1

_- /~')

Title:

Auxiliary Feed Pump Turbine Main Steam Inlet Isolation Valve

\d (MS-106) Problem Analysis Report by: .Neal L. Bonner Plan No. 27  ;

Date prepared: June 26, 1985 Page 1 of 3 This report has been' prepared in accordance with the " Guidelines to Follow When Troubleshooting or Performing Investigative Actions.into the Root i Causes Surrounding the June 9, 1985 Reactor Trip," Rev. 4.

i INTRODUCTION i

j This report is intended to analyze known information concerning the apparent interruption of the open control circuit to Auxiliary Feed- Pump  ;

3 Turbine 1-1 Main Steam Inlet Isolation Valve (MS-106). During the event, MS-106 apparently cycled in about one third of the expected stroke time.

It will be the intent of this r(port to support the action plan for t determining the root cause of the anomalous operation of MS-106.

.j

SUMMARY

OF DATA -

l Valve MS-106 is a normally closed valve and was closed prior to the ['

]

transient.

i j Early into the transient steam generator levels decreased to the Steam Feedwater Rupture Control System (SFRCS) low level trip setpoint. From O this SFRCS steam generator low level trip.the open circuitry to MS-106 received an initiation. Activation of the SFRCS trip and indication of MS-106 opening is indicated by the alarm printout respectively. Approxi-mately two seconds after MS-106 showed position change,- the operator j action of manually tripping the SFRCS on main steam line low pressure >

occurred and is also recorded on the alarm printout. From the initial j activation of SFRCS, MS-106 should have gone open to the full open posi-  ;

j tion. The operator initiation of SFRCS should have given MS-106 a close i circuit permissive. Once MS-106 had reached full open, its close circuit- ,

I ry would have been completed via one of its own limit switch contacts.

MS-106 would then have started in the close direction. MS-106 was indi-cated closed by the alare printout approximately 19 seconds after the original SFRCS steam generator level signal to the alarm printout was 4 received.

! t MAINTENANCE AND SURVEILLANCE / TESTING HISTORY Based upon a review of data from ST 5071.01 it was determined that MS-106

] normal stroke time from closed to open is approximately 25 seconds.-

j Likewise, the open to close cycle occurs in approximately 25 seconds.

In a review of past maintenance data both on Davis-Besse Maintenance.

t- Management System (DBfftS) and from Records Management the most recent j

Maintenance Work Orders (MWO) were 2-82-0119-00 and 1-82-2787-00. Both of ,

l these NW0s were completed in 1983. [

!O ,

i i

! . 5

_ _ _ _ . , _ . _ _ . - - _ - - - - _ - - - _ _ _ . . _ . _ .. _ _ _ . _ . . _ _ _ . _ , _ . .. m _ _._

d

, g'~3 Based on the review of the above mentioned MWO's and that of recent

( ,)

~

ST 5071.01 data (5-23-85), there is no information which would indicate that MS-106 should perform other than as designed.

CHANGE ANALYSIS The operation of MS-106, in the manner observed during the transient, apparently went from closed to open to closed position in approximately 19 seconds. The most recent test data from ST 5071.01, which was re-viewed, indicates a time of approximately 25 seconds for MS-106 to open and approximtaely 25 seconds to close. A total time of approximately 50 seconds for a close to open to close operation. It is the evident difference between operating times (19 seconds versus 50 seconds) which will be the basis for hypotheses. These hypotheses will be contingent upon one of two assumptions:

1. The valve operator motor for MS-106 significantly increased in speed (rpm).

2. The open control circuit failed in such a manner to preclude MS-106 from going to full open. Thus MS-106 would have stopped in some intermediate position and then returned closed. This would decrease the overall time for close to open to close operation.

HYPOTHESES 7s The information collected and reviewed from before, during and after the

(' ) transient, indicates that a much shorter (~1/3 the normal time or ~19 seconds) time elapsed for the close to open to close cycle of MS-106. The follow-ing is a list of the hypotheses which could cause MS-106 to act in this manner. These hypotheses were reviewed and discussed for plausability with F. R. Miller, Nuclear Systems and Analysis Engineer, and S. C. Jain, Davis-Besse staff Senior Nuclear Engineer.

1. An open in the field circuit to the compound wound de motor driving the operator of MS-106. .

2. An open or misoperation in the 42a/0 contact seal in circuit.

3. Improper operation of MS-106 valve operator open and close circuitry due to possible wiring errors of SFRCS contacts into valve control circuitry.

4. Improper operation of pressure switch PSL 4930A and/or its auxiliary 1 relay PSL 4930X1 which provides a permissive for both the SFRCS open initiation and the 42a/0 seal in contact.

5. Improper operation of either relay R1 or R3 contacts 2-7 or their .

associated coils. These are auxiliary relays in the main steam line pressure switch logic which provides a permissive to the SFRCS open circuit logic and the 42a/0 open seal-in. This particular hypothesis may be discounted based on the following reasons.

O

i

, /"' a. The low steam line pressure logic takes 25 seconds to pick up

( ,)s after MS-106 has given the logic a full open permissive. As has been shown previously MS-106 opened and closed in ~19 seconds.

Therefore, Ms-106 was never open long enough to maintain the permissive to allow the logic time to pick up, i b. MS-106 opened successfully after the improper manual operation of SFRCS was reset and SFRCS returned to its previous trip state. This would not have happened if either R1 or R3 contact 2-7 had failed opened during a previous operation of the logic.

This would require a one time only failure of one of the two contacts.

c. Since the pressure switch logic is normally deenergized (with pressure available) there is no reason to believe that the 2-7 contacts of relays R1 and R3 ever changed state to provide for a mode of failure,

d. No alarm was received giving an indication of activation of i logic.

4

6. Improper operation (opening) of the torque switch open, due to ,

! improper setting of the torque switch 33/to, g

a .

7. Out of adjustment setting on the open limit s kitch contact No. 4 (33/bo).

() Hypothesis #1 deals with the assumption of the valve motor increasing in speed.

Hypotheses #2-#7 deal with the assumption that MS-106 open circuitry I malfunctioned causing the valve to reverse direction at some intermediate position.

3 i

se d/ll i

i I

i I

i lV .

f

..- ._- , - - . - . . . - _ - , . _ , - . . .c. _, , , - _.. ,_._.. _m.,_.v._ - , - - _ , . , _ .

ACTM PLAN PL AN NUMitE H PAGE

• • • as REV. 1 27 1 a' 6 TITLE oATE PREPARED PREPARED BY AUXILIARY FEED PUMP TURBINE MAIN STEAM INLET ISOLATION (MS-106) PROBLEM ANALYSIS 6/20/85 N. Bonner SPECIFIC OuK CTIVE  !

To determine the root cause of motor operated valve MS106 to operate in a shorter amount of time, during the transient of 1 June 9. 1985. than the recorded stroke test data.

STEP PftlME ASSIGNED START TARGET DATE NUM8ER RF SPONSIBILIT Y TO DATE DATE COMPLETED All steps of this action plan are to be performed in accordance _ _

with the latest revision of " Guidelines to Follow When Trouble-shooting or Performing Investigative Actions into the Root Causes Surrounding the June 9. 1985 Reactor Trip". __

]

NOTE: All steps to be performed in sequence. -. --

NOTE: Vendor support from MOVATS is required for steps 13.14&l5 1 Before beginning troubleshooting work at the MCC DINA starter N. Bonner ' ~

D135, document the as-found conditions of the starter. In per-forming this step, it will require that the door to the starter be opened. In performing this step, limit the gathering of the 4

as-found information to that which can be recorded without _

changing conditions, i.e.. general conditions, environmental conditions, etc.

2 Before beginning troubleshooting work at the valve, document N. Bonner the as-found condition of the valve and operator MS106. In 4

performing this step limit the gathering of the as-found infor-

_"*E1 n t t{atwhichcanberecordedwithoutchangingcondi-l so 27

/'~ N /7 ~

v} (

(m) s v

)

ACTION PLAN PLAN N UMh E 64 PAGE l ' awe _ _ _ _ .REV._1 .__

27 2 a' _ 6 TITLE 0%TE PHEPARE D PHEPARED BY l AUXILIARY FEED PUMP TURBINE MAIN STEAM INLET ISOLATION (MS-106) PROBLEM ANALYSIS 6/20/85 N. Bonner SPE CtF 0C OBJE CTIVE l To determine the root cause of motor operated valve MS106 to operate in a shorter amount of time, during the transient of June 9, 1985, than the recorded stroke test data.

STEP R A I N ARGET DATE NUMBER ACTION STEPS RFSPONSIBILITY TO DATE DATE COMPLETED tions, i.e., valve position, general condition, environmental conditions, etc.

3 Remove the cover on MS106 valve operator and inspect the N. Bonner operator limit switches, torque switch and all wiring. Record the torque switch settings. These settings should be 2.5 open and 1.5 close.

4 Perform a wiring check of the valve operator compartment. N. Bonner Verify the viring with Bechtel drawing E-557A sheets 77A and 77B. Pay particular attention to possible bad connections.

5 Perform a wiring check at MCC DINA of starter D135. Verify N. Bonner the wiring using Bechtel drawing E280A, sheets 29 and 29A and the Westinghouse starter internal wiring diagram 6798A39WD-1 (Bechtel vendor drawing #7749-E-8-139-3). Pay particular attention to loose connections or broken wires.

6 Perform bridge resistance readings of the series and shunt N. Bonner field windings. These readings are to be taken (if practical) at the MCC starter D135.

cv 27

A

p. 7 ~]

A ,

ACTION PLAN PLAN NUMHE #4 PAGE n uas REV. I 27 _

3 a' 6.

TITLE DATE PREPARED PREPARED BY AUXILIARY FEED PUMP TURBINE MAIN STEAM INLET ISOLATION (MS-106) PROBLEM ANALYSIS 6/20/85 N. Bonner sPacir.c cancTive To determine the root cause of motor operated valve MS106 to operate in a shorter amount of time, during the transient of June 9, 1985, than the recorded stroke test data.

STEP PRIME ASSH3NE D START TARGET DATE A

NUMBER HFSPONStBILITY TO DATE DATE COMPLETED 7 Perform a visual inspection of PSL4930A and document the as-N. Bonner found condition of this pressure switch. In performing this __ _ _ _ _ _ _ _ _ _

step, limit the gathering of the as-found information to that which can be recorded without changing conditions, i.e. general condition, environmental conditions, or system conditions, etc. -.

8 Perform a viring check of PSL4930A. Verify the wiring using N. Bonner Bechtel drawing E632B, sheets 2 and 6. Pay particular atten-

~ _ . . - ..

tion to bad connections.

9 Perform a calibration check of PSL4930A.

N. Bonner 10 Perform a functional check of PSL4930A and its, auxiliary relay N. Bonner PSL4930XI. This step will require that starter D135 control circuit power be made available by closing the main disconnect to D135. This step includes, but is not limited to the follow-ing:

a. Activate PSL4930A by means of an appropriate pressure source,

b. Monitor and time contact 4-6 of relay PSL4930XI upon de-pressurizing of the source to PSL4930A. This monitoring and e- -- _. . - - .-

cp 27

, ACTION PLAN

• " Pta r4 eeuwsE n PAGE

_ _ _ _ _ _ .__ _ _ _ _ m .. REV._1 _ __ _ 27 4a 6.

___j_

T6T LE j

DATE PRE PARE D PREPARE D BY AUXILIARY FEED PUMP TURBINE MAIN STEAM INLET ISOLATION (MS-106) PROBLEM ANALYSIS 6/20/85 N. Bonner 1

SPEC 4F #C 08JE CTivE To determine the root cause of motor operated valve MS106 to operate in a shorter amount of time, during the transient of June 9, 1985, than the recorded stroke test data.

STEP PHIME NUM8ER A 4 N S EM ASSIGMD START TARGET DATE RF$PONSIBILITY TO DATE DATE COMPLET ED I

timing of contact 4-6 of relay PSL493011 should be done at  !

1 1

MCC DINA starter D135.

i

_ .11 Perform a visual inspection of cable ICD 135G at control room N. Bonner i

i cabinet C5762A. Note general conditions of terminations I

without physically disturbing them.

12 Perform a wiring check of cable ICD 135G terminations at control N. Bonner

, room cabinet C5762A using Bechtel drawing E545 sheet #1.

13 Stroke MS106 and monitor the operation of the valve / operator N. Bonner

( _

using Motor Operated Valve Analysis and Test System (MOVATS) _

and any additional instruments as necessary. During the opera-tion of the valve MS106 the following should be done:

a. Set up the control circuit (i.e. Jumpers / lifted wires for permissives and initiation) to cause the valve to cycle open and then shut, via initiation from the SFRCS cabinet C5762A.

Initiate the open of MS106 via a momentary jumpering of

_ the output contact from SFRCS to the valve open circuitry.

_Approximately 2 seconds later jumper out the output from cp 27

O > O. .

ACTION PLAN NPNEHE M PAGE ,

ase4ee

- - - - - - . . - _ - . ,_- ., .REV. I 27 5 e ' 6.

AUXILIARY FEED PUMP TURBINE MAIN STEAM INLET ISOLATION (MS-106) PROBLEM ANALYSIS 6/20/85 N. Bonner

$PEclFIC OB JE CTivE To determine the root cause of motor operated valve MS106 to operate in a shorter amount of time, during the transient of June 9. 1985, than the recorded stroke test data.

STEP PRIME i A TION STEPS ASSIGNED STANT TARGET DATE NUM8ER R F SPONSIBILITY TO DATE DATE COMPLETED SFRCS to the valve close circuitry to provide a main-tained close contact permissive to close MS-106.

L b. Record time required for the closed to open to closed

~

operation of MS106.

c. Observe operation of the limit switches and torque switches. _

(See NOTE on page 1) f 14 Stroke MS106 open and monitor the operation of the valve using N. Bonner l MOVATS. (See NOTE on pa p 1) 1 15 Stroke MS106 close and monitor the operation of the valve using N. Bonner  :

MOVATS. (See NOTE on page 1)

[ 16 Manually operate the valve MS106 from close to open counting N. Bonner i the number of turns to each of the following:

, a. Torque switch 33/TO bypass contact 33/ac-#5.

b. Limit switch contact 33/bO-#4 contact to drop out open circuitry.

i

c. Valve full open.

{ 17 open connections to isolate the series field winding, shunt N. Bonner cp 27

e'- - .

e, ACTION PLAN esene 'AA P EsMHEH PAGE .

m 1tEV. 1 . 27 6 o' 6 AUXILIARY FEED PUMP TURBINE MAIN STEAM INLET ISOLATION (MS-106) PROBLEM ANALYSIS 6/20/85 N. Bonner >

SPECIFIC OGJECTIVE To determine the root cause of motor operated valve MS106 to operate in a shorter amount of time, during the transient of June 9, 1985, than the recorded stroke test data.

STEP PHIME A TION STEM ASSIGNE D START TARGET DATE NUMBER nrSPONSIBILITY TO DATE DATE COMPLETED field winding and shunt field resistor. Measure resistance of each of these components. This may be done at the starter D135.

1 18 If the above steps do not produce a root cause, additional '

valve exercising and testing may be conducted with the system pressurized.

1 1

i i--

)

cp 27 >