Automated on-off valves play important roles in many systems, including starting and stopping batch processes, routing process fluids, filling and emptying tanks, backwashing filters, performing safety shutdown functions, and more. These valves are often required to operate reliably for years of continuous service.
In both new and existing plants, smart valves featuring microprocessors and digital communication capabilities are becoming increasingly common. In our article from the September/October 2023 edition of Valve World Americas, titled “How Digitized On-Off Valves Improve Operations,” we discuss how smart technologies are used in these valves to provide remote monitoring, data analysis, and predictive maintenance.
This smart digital on–off pneumatics valve assembly includes a microprocessor-based device to perform various diagnostics functions.
Limitations of traditional on-off valves
Most on-off valves are not monitored remotely, so developing issues aren’t detected.
Traditionally, on-off valves were automated with a separate solenoid valve, two feedback limit switches indicating an open or closed position, and in some cases a position transmitter. The common challenge with the feedback limit switches and position transmitters was their significant alignment and mounting issues.
Over time, mechanical degradation can lead to a wide variety of problems. Without remote monitoring capabilities, these valves require regular onsite preventative maintenance to ensure continued functioning. As they often remain in one position for long periods of time, there is concern that they may fail to actuate when needed.
Different types of diagnostics are available from electric actuators
Digital solutions
Equipping an on-off valve with a smart digital controller addresses most common issues. These controllers provide critical valve health diagnostic information, increasing uptime and optimizing maintenance efforts. Connection is simple, requiring only a single pair of wires to communicate with a host system.
This intelligent on-off valve includes Emerson’s Bettis XTE digital electric actuator.
Digital controllers use advanced sensor technology, data collection and analysis, and secure communication systems to provide several benefits:
- Continuous performance monitoring enables any anomalies from normal operation to be identified and reported promptly, reducing the risk of unexpected failures and downtime.
- By analyzing operation trends and patterns, predictive maintenance can be scheduled at the optimal time.
- Valve technicians can access diagnostics remotely to perform support and troubleshooting, reducing on-site visits and the need for direct access to valves in difficult locations.
- Data analysis can reveal inefficiencies that can be addressed to optimize performance.
Actual (gray) versus reference (red and blue) torque profiles for an electrically operated valve.
Data-Driven Decisions
Online diagnostics provide insights, leading to better decisions regarding process optimization, maintenance, replacement, and upgrades. Valve signatures also serve as a benchmark for future comparison to detect performance degradation.
Digital Trends
While traditional valves do not support digital communication protocols, modern plants are increasingly incorporating smart valves into digital networks alongside many other field devices. Field device diagnostics are key for optimizing productivity, efficiency, and product quality, as well as moving from reactive/preventative maintenance to predictive maintenance.
Visit the Actuators section on Emerson.com for more on these and other smart devices to help you improve operational performance and maintenance practices.
