Controls and Valves 4.0: when will systems go wireless?
Besides process control systems and sensors, actuators play an important role in automation and process engineering.
Controls and valves can adjust material flows to regulate process parameters such as pressure, temperature, flow rates and fill level. “Intelligent” control valves with add-on modules are available which not only perform the control function but also automatically detect the need for maintenance or repair before a fault occurs. In the final analysis, these smart controls and valves improve production reliability, increase cost efficiency and help protect the environment. Suppliers expect that actuators will be used to a greater extent in control loops in the future. This could ultimately lead to wireless control. The actuator technology already exists.
Wireless sensing is a promising branch of sensor technology. Wireless measurement data transfer is not really new, but its potential in the industry has only recently been recognized. The technology looks very attractive but there are hurdles to overcome such as real time capability and reliability, and they are slowing the pace of introduction.
Actuator systems continue to rely on the traditional technologies: electric, hydraulic, pneumatic and electrohydraulic. But even here, more and more control and diagnostic functionality is being built into the drives. This is another application for distributed intelligence.
Electric valve actuators have the advantage that they can easily be connected even over large distances and they are relatively lightweight. Pneumatic systems have short actuation times and withstand long duty cycle ON times. However the actuator is large and heavy. Hydraulic systems are maintenance intensive, but a smaller actuator generates more force compared to a pneumatic system.
One supplier is currently talking about a paradigm shift in single-use technology. Manual systems can be replaced with devices suitable for automation and control which support fault-free operation and continuous documentation by the monitoring system. The valve body and the actuator on the new product are connected using a special locking mechanism. Following use, the valve body is removed and the actuator remains in the system for repeated use. If necessary, the valve actuator can send feedback to the monitoring system, adding the final element needed to fully monitor the control loop. The manufacturer claims that this approach facilitates process reproducibility, documentation and validation in pharmaceutical production.
Want to find out more? Come to AchemAsia 2016!