South Texas
Project
Feed Reg
Valve
Positioner
Replacement
2008 User Conference& Technology Fair
Process Automation Systems Integration Summary
10 Years of Integration and Still Growing
PAS
ValVue 2
ValVue FF
Fault
Models
FVP
ESD/PST
ValVue
ESD/PST
DTM
eDDL
FDT/DTM
Honeywell
Experion (AM)
Yes
Pending 10
Yes
Yes
Yes
Pending
Yes
Yes
Yes
N/A
N/A
Yes
Pending
Yes
Yes
Yes
No
No
No
Pending
No
No
No
No
No
Pending
10
No
Yes
No
No
No
No
Yes
No
Yes
No
No
No
No
No
No
Yes
*
*
ONLINE VALVE DIAGNOSTICS
Page.3
MAIN PURPOSE FOR REPLACEMENT
• Obsolescence of remote mount Hall Effect
Westlock Model IcoT 4300.
• One spare positioner.
• No spare parts.
• No vendor/mfgr support.
• Remaining spares were refurbished.
• Existing Valve-Copes Vulcan 16x12x16
with D100-160 Actuator
4
PREFERENCES
•
•
•
•
Positioner with a long manufacturing life
Repeatable, accurate calibrations.
User friendly software, setup, & tuning.
Reliable,solid position feedback &
linkage for Direct Mount.
• Good industry history.
• Excellent Viper20 test results.
• Laptop communications.
5
MODELS EVALUATED AND TESTED
• Fisher DVC6000 – Industry standard.
• Westlock ICoT 5300 – Direct
replacement for obsolete Model ICoT
4300.
• Masoneilan SVI II AP – Good industry
feedback.
6
MASONEILAN SELECTED
7
MASONEILAN SELECTED
8
MASONEILAN SELECTED
• Very positive Industry feedback.
• Ease of installation, setup, tuning,
software.
• Consistent, accurate and expected
response.
• Ruggedness of design for direct mount
and reliable history of hall effect design.
• No need for redundant positioners
based on industry OE of Feed Reg
Digital Positioner Failures.
9
INSTALLATION PLANS
• 100 hour burn-in of all for-use and spare
positioners.
• Full set up and testing on mockup of all
for-use and spare positioners.
• Setup, calibration, and tuning techniques
developed before installation.
• New cal procedure incorporated into
installation work package.
• Management focus briefing held
• Liberal use of vendor experts.
10
CONTINGENCIES
• Replace positioners if individually fail.
• Replace with original Westlock positioners if
generic issue.
• Scheduled on-line tuning.
11
ON-LINE TUNING CONTINGENCY
• Tuning contingencies scheduled
• Work packages developed
• JIT conducted - tuning changes
practiced
• Operating procedures developed and
tested
• 2 sets of tuning parameters developed
for overshoot or oscillation issues
12
ISSUES
• Different firmware version than was
tested on mockup.
• Caused unexpected testing results
during 0.5% Step Test.
• Vendor flashed EPROM to preferred
version – problem solved.
• Site error in not ordering specific
version.
13
SUCCESSES
• No positioner failures.
• No un-expected test results (after
firmware flashed) .
• Modification invisible to Operations.
• Utilized PID parameters determined by
auto-tune feature.
• Fast setup and testing-30 minutes.
• No on-line tuning required.
• No oscillations or overshoot.
14
SUCCESSES
• No conflict with Westinghouse 7300
• Stable valve control.
• PMT automatically conducted by the plant
(secondary upset).
• Valve gagging technique developed.
• Installed in Both Units 1 & 2.
• Thermal Aging testing by Masoneilan and
monitoring of on-board temperature will
determine future PMs.
15
SUCCESSES
Crane Viper Testing-The step changes are 5%, 2%,
1%, and 1/2% from left to right, centered for the
valve at normal operating position for 100% power.
At ½%, the valve is responding with 0.015inch
changes. Live Data shows tighter control but
outside test criteria.
16
South Texas
Project
Feedwater
Heater Level
Control
Upgrades
A Low Cost
Approach to
Reduce High
Cycling
•Mr. JR Price, STP
•Mr. Kurt Christianson, Enertech
Background
• South Texas Project is a 2 unit 1350MW Westinghouse 4 Loop PWR.
• A power uprate of 1.5% was made to each plant.
– This caused the control valves for 2 medium pressure feedwater
heaters to go full open.
– A subsequent trim upgrade allowed the valves to start controlling,
but the feedwater heater levels and control valves also started
cycling.
• Level control valves and feedwater heater levels cycled more than 10
million times a year, oscillating every 3 seconds
– Pneumatic controllers do not have many options for fine tuning,
and the cycling could not be tuned out.
– Due to 250ft of pneumatic signal tubing, a control delay contributed
to high cycling.
Problem
• Valve internals and actuators were failing every 6-9
months.
– Unscheduled on-line rework was required.
– The plant suffered MW losses while on the high level
condenser dump valves.
– Failures during the summer challenged the
maintenance personnel due to extreme heat.
– Valve locations in a hot environment that required
extensive scaffolding.
• Valve actuators were modified to obtain more life by
installing high temperature soft goods and high cycle
parts.
• After modifications, life was extended but full rebuilds
were required every outage to prevent failure mid-cycle.
System Overview
Solution
• Replace pneumatic positioners and
controllers with digital positioners and
controllers.
• Utilize standard 4-20ma loops for
simplicity and diversity
• Install redundant power supplies.
• Use HART® communications for user
interface.
Equipment
 In each control loop:
– 2 Masoneilan SVI® IIAP double acting positioners
with non-contact hall effect position feedback
mounted on Valtek piston operated valves.
– 1 Masoneilan 12300 level controllers mounted on
existing FWH level controller cage.
– 2 Phoenix Contact QUINT-PS-100-240AC/48DC/5
power supplies wired in redundant (parallel)
configuration DIN rail mounted
– 2 blocking diodes per power supply
 Laptop for positioner and controller communications with
ValVue software
Testing and Training
• Extensive testing in the I&C lab with a mockup that
includes the level controller and cage, two Valtek
actuators, and redundant power supplies.
• Testing included:
– Positioner and level controller setup, selection of
initial operating parameters, positioner mounting,
controller mounting and connection, loop control and
valve response, trouble shooting.
• Training with the Masoneilan representative on site.
• Certification on the mockup.
Mockup of Controller
Power
Supplies (2)
Level
Controller
Cage
Mockup for Positioner
(Mounting Kit)
Masoneilan SVI II AP Positioner
Implementation
 Masoneilan representative assisted during installation.
 Initial selected tuning settings were not effective.
 High FWH and control valve cycling during initial startup
because of insufficient and unstable flow through control
valves at lower power. Conditions became more
favorable above 50% power.
 Auto-tune was utilized at a hold point of 77% power.
 Auto-tune in conjunction with higher flow rates stabilized
the valves and level completely.
Fisher Level-Trol Pneumatic
Controller
Masoneilan 12300 Digital Level
Controller
Masoneilan SVI-II Digital
Positioner
Before Auto-Tune (controller)
After Auto-Tune (controller)
After Auto-Tune at Power
(controller)
Results
• Elimination of FW Heater level and valve cycling.
• Significant reduction in maintenance costs.
• Low cost solution compared to stand alone control
system such as a PLC.
• Increased morale of technicians & system
engineer.
Additional unmeasured:
• Recovery of some lost MW due to improved level
control.
• Improved life of feedwater heaters
Keys to Success
 Solid management support of project
 Extensive testing in I&C lab
 Vendor support
 Auto-tune and filtering on controller
Keys to Success
 Solid management support of project
 Simplified installation of digital controller on
existing displacer cage
 Hall effect sensor and rugged mounting of
positioner
 Digital Instrumentation compatible with
future DCS system upgrades