ML042960355
| ML042960355 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 10/18/2004 |
| From: | Straka D Arizona Public Service Co |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| FOIA/PA-2004-0307 | |
| Download: ML042960355 (2) | |
Text
A -0V 1138 dCO C-Tony:
Our current information on Testing Performed for Unit 1 ADV 185.
- Regards, Don Straka Senior Consultant - Regulatory Affairs dstrakafapsc.com phone: 623.393.5041 pager 602.509.6240 mobile: 602.509.6240
> -Original Message-
> From:
Berg, D. Lee (Z99751)
> Sent:
Thursday, July 01. 2004 5:11 PM
> To:
Straka, Donald J(Z99942)
> Cc:
Smyers, Daniel W(Z89227); Fisher, Daniel A(Z99305); Landstrom,
> Carl E(Z98901); Jones. Stephen 8(Z02094); Powell, Michael E(Z99700);
> McGhee, Mark A(Z65028); Fernandez, Amado T(Z02065); Muhs, Michael
> K(Z69505); Winter. Christian S(Z01491); Jones, Warren H(Z54741)
Subject:
Testing Performed for Unit I ADV 185
> Don,
> I was asked to update you regarding the testing performed and the
> final outcome for Unit I ADV 185. This valve was Identified by
> operations as having erratic operation during recovery from the most
> recent trip. It appeared to operations that the valve was changing
> positions with no demand change from the control room. At least one
> time operations Indicated that the valve went closed far enough to
> have Indications In the control room that It was full closed. To find
> the cause for this Issue three revisions to the action plan were
> issued.
> Revision 0
> ADV 185 was Isolated from the steam source and stroked to the 50% open
> position looking for any Indication of drifting. Instrument air
> fittings and associated parts were SNOOPed to locate leaks. The valve
> was Instrumented to watch I/P signal and valve position.
> During the stroking no anomalies were discovered, also no leaks were
> detected.
> Revision I
> Under this revision the ADV was stroked with steam using
> Instrumentation monitoring the actuator and valve bonnet pressure.
> During this stroke the valve again behaved as expected. The bonnet
> pressure was found to be approximately 10 psig Power than coming out
> of the last outage, -29 psig). The actuator pressures were similar to
> past traces performed on other ADVs. The valve was held open for about
> 3 minutes for this test. It was determined that the valve operated as
> expected.
> Revision 2
- This revision combined the previous the action plans with minor
> modifications. The control system (actuator, positioner. I/P, and
> demand signal) of the ADV was instrumented to detect any Issues that
> might occur. It was also decided that the stroking would be performed
> similar to that reported from the area operator during trip recovery.
> A series of three strokes were performed, as outlined below. All
> strokes were with steam Isolated.
Provide a demand signal of 80% open. When the valve traveled to
> 20% open change the demand to 30% open. Leave the valve In this
> position for 20 minutes. After 20 minutes fully close the valve.
The second stroke was the same as the first except the Initial
> demand was 50% open.
The third stroke had an Initial demand of 50% open. When the
> valve achieved 15% open the valve was taken to 20% open. The demand
> was left at this point for 20 minutes.
> All three strokes behaved almost identically. The difference between
> demand and actual position was about 14%. This has been consistent
> from the time the valve was last calibrated during the UlR1 I outage
> through the series of five strokes described above. When that valve Is
> given a demand there Is a normal lag In time prior to the valve
> moving. This Is due to the long tubing run between the I/P and the
> valve positioner (-110 feet). Once the demand was given the UP
> started changing pressure as expected to allow the positioner to port
> air to the bottom of the actuator to start opening. This function
> occurred as expected. No anomalies were detected In any of the
> strokes. At no time did the ADV move from the desired position over
> any of the three 20 minute time frames.
> Based upon the response of the valve as seen In the Instrumentation
> response charts ADV 185 Is functioning similar to other ADVs observed
> under the same conditions. The anomalies Identified by operations
> could not be recreated. Engineering cannot find any problem with the
> operation of this valve or recreate the anomalies reported by
> operations.
> In looking at equipment history I/C determined that the positioner Is
> approximately 6 years old. Based upon the age of the positioner and
> not being able to recreate the described anomalies It was decided that
> the positioner would be replaced (WM# 2715990) and calibrated. No
> further actions will be performed at this time. When the positioner is
> replaced and calibration Is completed operations has Indicated the
> valve will be declared operable.
> If you have any questions please call me at work or home.
> Lee Berg
> Work 623-393-3676
> Pager 602-746-2498
> To hike Is to live; to hike with family Is to live In heaven'