Actuating Valves – Actuated Valves and Automated Valves with Pneumatic Actuators or Electric Actuators
With ever-increasing automation in the chemical process industries, actuated valves are becoming more and more popular. Actuation simply means that valves open and close automatically without the need for human intervention. This is done using motors and other powered mechanical devices known as actuators. AU of the manually operated valves mentioned in this article can be actuated. The two main types of actuators are electric and pneumatic.
they are relatively inexpensive, lightweight, and reliable. Pneumatic actuation is very efficient when multiple actuators are present, especially for systems containing more than 20 valves.
These valves need an air supply, so if compressed air is not present, installing such a system for just a few valves does not make sense. In addition, initial installation can be cumbersome, since pneumatic lines must be run to each valve.
Electrically actuated valves, on the other hand, are very easy to set up. They are ideal for systems with a small number of actuators (fewer than 20). Unlike pneumatic actuators, electric actuators do not require a compressed air system, but they are more expensive and complex.
An important accessory for actuated valves is a positioner, which transforms an on/off valve into an automated flow control device by continually and precisely moving the valve to the desired position. Positioners are available for both pneumatic actuators and electric actuators. Automatic tank filling, chemical blending, and pH neutralization are a few examples of applications where computer-controlled valve automation may be found.
Valve actuation becomes very powerful when combined with computers, PLCs, and sensor feedback.
Valve Testing Results
The basic technologies described here are the most commonly used valves in the chemical processing industry. The information presented should aid in the general selection of valves. Process requirements, chemical capability, and pressure and temperature considerations should also be considered.