ML042960374
| ML042960374 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 07/02/2004 |
| From: | Straka D Arizona Public Service Co |
| To: | Gody A Office of Nuclear Reactor Regulation, Division of Reactor Safety IV |
| References | |
| FOIA/PA-2004-0307 | |
| Download: ML042960374 (3) | |
Text
From:
<DSTRAKA@a sc.com>
To:
<atg@nrc.gov>W\\r*
V\\ 4 l
Date:
7/2/04 11:43AM I
Subject:
RE: Testing Performed for Unit 1 ADV 185 Tony:
Our current information on Testing Performed for Unit 1 ADV 185.
- Regards, Don Straka Senior Consultant - Regulatory Affairs dstraka apsc.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 B(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 1 ADV 185
> Don,
> I was asked to update you regarding the testing performed and the
> final outcome for Unit 1 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 1
> 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 (lower 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 UI RI 1 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 I/P
> 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" CC:
<DMAULDIN@apsc.com>, <DSMYERS@apsc.com>,
<DFISHE01@apsc.com>, <CLANDSTR~apsc.com>, <SJONES03@apsc.com>,
<MXPOWELL@apsc.com>, <MMCGHEE@apsc.com>, <AFERNAOI@apsc.com>,
<MMUHS@apsc.com>, <CSWINTER@apsc.com>, <WJONES03@apsc.com>