ML20129D607

Rev 0 to Action Plan 18, Startup Feed Valve SP-7A Problem Analysis

ML20129D607
Person / Time
Site:	Davis Besse
Issue date:	06/22/1985
From:	Gulvas T, Uebbing R TOLEDO EDISON CO.
To:
References
NUDOCS 8507300108
Download: ML20129D607 (5)

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D ACTION PLAN g 18 TITLE: Startup Feed Valve SP-7A Problem Analysis i

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4 CHAIRMAN REV DATE REASON FOR REVISION BY TASK FORCE O 6/22/85 Initial gg j7g_ _

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TITLE: STARTUP FEED VALVES SP-7A PROBLEM ANALYSIS REPORT BY: Ron Uebbing/ Tom Gulvas PLAN NO. 18 DATE PREPARED: June 22, 1985 PAGE 1 of 2 This report has been prepared in accordance with the " Guidelines to Follow when Troubleshooting or Performing Invertigative Actions into the Root Cause Surrounding the June 9, 1985 Reactor Trip", Rev. 4.

INTRODUCTION:

The following report is the analysis and evaluation for determining if there were problems associated with the operation of the Main Feedvater #2 Starup-Control Valve (SP-7A) or its controls during the June 9 transient.

SUMMARY

OF DATA:

SP-7A is normally open when above 20% power. During the transient SP-7A when closed automatically due to the initiation of SFRCS. After the SP-7A SFRCS trip was reset by the operator, SP-7A did reset properly. The SP-7A Channel 4 reset switch indicating light did not indicate this reset. The ejerator requested that the I&C technician replace the indicating bulb in this switch. A bulb was removed from the Channel 1 indicator and placed in the Channel 4 indicator by the technician to save time in verifying SP-7A reset status; this bulb blev immediately.

The alarm printout indicates that SP-7A and SP-7B startup feedwater valves reset at the same instance, this verifies the reset circuitry. i Additional verification of proper reset action of SP-7A is present in the DADS printout which reveals that main feedwater startup flow was estab- i lished through loop 2 (SP-7A) and loop 1 (SP-7B) at the same point in 4

time. SP-7A and SP-7B position printouts verify this. This printout also shows the removal of main feedwater flow as auxiliary feedwater flow was i reestablished.

The SP-7A flow printout is higher than SP-7B and does not fall below 74 thousand pounds per hour when SP-7A and SP-7B are closed. This indicates the need to check the calibration of the flow measuring instruments associated with the operation of SP-7A.

As a followup, when time was available (about 0800, June 9,1985), the SP-7A Channel 4 replacement indicator light bulb was checked and found to be the wrong voltage rating, 6 volt instead of the required 120 volt, the proper bulbs were installed in both channels and worked properly. ,

SP-7A SFRCS trip and reset logic is tested monthly under ST 5031.14, Sections 6.2, 6.3 and 6.4, and has recently shown no problems to be associated with the reset indication.

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o' ,,s 2 of 2 CHANGE ANALYSIS:

Not required.

HYPOTHESIS:

1. Startup feed valve SP-7A did function properly. The operator had no indication of proper reset function due to the reset indicating lamp failure. The lamp failure was due to random or normal end of bulb life, or to a voltage spike in the reset circuit.

2. SP-7A did not respond correctly. The actdbn plan will address this hypothesis by the collection of data to show if there could have been flow through SP-7A.

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PLAN Nouritei Pact ACTION PLAN a' 2 o r.ee ._

Rev. 0 18 1 TITLE DATE PH[PAliE D PHEPAREO BY Startup Feed Valve SP-7A Problem Analysis 6/22/85 Ron Uebbing/

srecIric oesterive _ Tom Culvas Verify the determination that there was not a failure of the main feedwater #2 startup control valve or its reset control circuits.

PRIME AS$1GNED START TARGET DATE STEP A TION STEPS COMPLETED RFSPONSIBILITY TO DATE DATE NUMsER All steps of this action plan are to be performed in accordance T. Gulvas with the latest revision of " Guidelines to Follow when _

Troubleshooting or Performing Investigative Actions into the Root Causes Surrounding the June 9, 1985 Reactor Trip".

10 Collect information regarding possible sources of flow through SP-7A at the time of the transient.

2 Ensure SP-7A is reset 3 Have operators open SP-7A at hand / auto station.

4 Trip SFRCS Ch. 2 & 4 on low steam generator level using " test" switches. _ . _

5 Verify SP-7A closes 6 With test switches held in block SFRCS 2/4 trip 7 Reset 5P-7AandverifySP-7Aopens,monitorchannel4 reset -

lamp voltage, and verify reset laep lights. .

8 Release test switches 9 Repeat steps 1 through 7 10 Return control of SP-7A to operations control

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' ACTION PLAN Plan Nuvotn PACE o o.. Rev. 0 18 2 a' 2 TITLE DATE PREPARED PREPARED BY Startup Feed Valve SP-7A Problem Analysis 6/22/85 Ron Uebbing/

SPE CIFIC oBJE CTIVE Tom Culvas Vsrify the determination that there was not a failure of the main feedwater #2 startup control valve or its reset c:ntrol circuits. ,f STEP PRIME ASSIGNED START TARGET DATE

^ I II RFSPONSIBILITY TO DATE DATE COMPLETED NUM6ER 11 Verify proper calibration of Main Feedwater 2 Startup flow indication instruments. .

11A If the Main Feedwater 2 Startup flow indication instruments are within specifications, check SP-7A for faulty position indication ,

11A1 If SP-7A position indication is correct, check SP-7A for closed leakage.

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• This step is not a prerequisite for the following steps and does _ _ _ _ _ ____ _

not need to be performed before proceeding with Step 2. _

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