actuator :
Introduction :
Introduction : The operation of control valves requires an actuator. The purpose of using an actuator is to change the position of the moving part of the valve in the desired position. The actuator converts the control signal of the system to the movement of the valve to open or closed state or the desired intermediate state.
Excitation of various types of controls can be done in different ways such as Pneumatic Actuators, Hydraulic Actuators, Electric Actuators and Manual Actuators
It is a mechanism for opening and closing the valve. Manual valves need at least one person to open or close them, which can be done by a direct mechanism or gearbox attached to the stem or handle of the valve.
Automatic actuators allow the valve to be easily and quickly remotely controlled by air pressure (pneumatic), hydraulic pressure or electric force in large valves. Actuators may only be able to fully open or close the valve; but in some actuators it is possible to adjust the exact position of the valve.
In most dairy companies, hygienic and process factories, actuators can be found on valves due to the implementation of automation. Actuators are an essential part of the process factory automation process
Pneumatic actuator :
Pneumatic actuator is a tool for converting compressed air energy into mechanical energy and is classified into two types of linear pneumatic actuator and rotary wind actuator in terms of type of movement.
Pneumatic actuator is widely used in various industries for valves of different sizes with rotational or linear motion, and this range is due to the possibility of providing compressed air for the actuator in most industrial centers, painless return of exhaust air to the open space of the workshop, simple pneumatic actuator mechanism. Low maintenance and the most important factor is the cheapness of pneumatic actuator equipment.
At the same time, the output of the control valve can be controlled by making changes such as adding a nominal solenoid valve to the pneumatic actuator, and giving the appropriate voltage-current to excite the pneumatic actuator.
Diaphragm actuators are a type of pneumatic actuator that are widely used.
Function :
In these actuators, compressed air is applied to one side of a flexible plate called the diaphragm and moves the disk inside the actuator up and down.
These actuators are single-acting, meaning that wind enters only one side of the aperture. These actuators are available in three modes: normal open, normal close, air / air.
