At the Emerson Exchange 2025 Conference, Control Southern’s Jordan Cain and Emerson’s Daniel Busch presented “Using Smart Valve Positioners to Cut Downtime and Optimize Outages”. Here is their presentation abstract.
Valve positioners are vitally important to the accuracy and reliability of a process control loop. Southeastern Combined Cycle Plant utilizes AMS ValveLink™ to extract real-time control valve health with Fisher™ DVC6200 PD-tier positioners to identify issues before they become operational problems. The plant partners with Emerson’s remote valve analysts to evaluate valve signature data and provide insight on time-based degradation. The partnership helps the plant prioritize urgent maintenance needs and reduce unplanned downtime.
They opened the presentation by highlighting some of the challenges manufacturers and producers face. The first is trying to improve plant reliability with fewer technicians. One combined-cycle power plant had six combustion turbines, three steam turbines, and 200 control valves. Only five technicians were responsible for maintaining all these assets.
Thankfully, digital tools help boost the productivity of these technicians, enabling them to maintain high reliability levels. These tools included FIELDVUE digital valve controllers, ValveLink diagnostics software, and the Ovation distributed control system (DCS). They also possessed historical valve maintenance data and had a preventive maintenance strategy in place.
The challenge was to use these tools and data effectively, as well as to determine the required expertise. They explored the option of Emerson’s Valve Condition Monitoring service. It is a diagnostic service focused on providing predictive analysis of the control valves, with the intent of identifying potential failures. By identifying potential issues early, technicians can take proactive measures or plan for them before a failure occurs, thereby avoiding costly unplanned downtime.
Emerson valve experts provide a monthly executive summary that includes, among other things, an overview of the monitored valves, any new emerging issues, and maintenance priority status—classified as significant impact, minor impact, or no impact.
The data collected that informs these monthly reports includes:
- Travel Deviation
- Relay Adjustment
- Drive Signal
- HART Alerts
- Supply and Output Pressures
- Internal Temperature
- Power Cycles
An example they shared was a FIELDVUE positioner reporting that the valve travel is not correctly responding to control signal changes. The potential impact was that the positioner and valve actuator were unable to move the valve from a closed position, either due to a significant failure or a manual override condition.
The recommendation was to investigate the FIELDVUE positioner’s feedback arm and bracketry for tightness and correctness. It referred the technician to the manual for further information. A frozen booster was discovered on the valve assembly during an investigation, and a repair was performed.
The monitoring service also identified several other issues, including low friction alerts, high relay adjustments, valves operating outside the ideal control range, and plug erosion.
The results of using this service were to place a greater focus on maintenance of critical valves, spend less time on valves already in good condition, and utilize the actionable information provided to optimize maintenance practices.
Visit the links above and the Valve Condition Monitoring section on Emerson.com to help you drive top-quartile reliability performance.
