Electric Actuator Valve Types

Figure 2 typical electric motor valve actuator.

Electric actuator valve types.

Position switches are utilized to indicate the open and closed position of the valve. There are two main types of actuators one for each of the two main types of valves that require them. Selection of the best actuator type for any application is dependent on many factors including. Linear electric valve actuators are used with gate globe diaphragm pinch and angle valves that feature a sliding stem that opens or closes the valve.

This power source can be electric pneumatic compressed air or hydraulic the flow of oil. Electric motors can be used to open close and position a valve manually automatically or semi automatically. The motor operates in both directions and drives the valve stem by means of gear couplings. Typically a declutching mechanism and hand wheel are included so that the valve can be operated manually should a power failure occur.

To protect the valve the torque sensing mechanism of the actuator turns off the electric motor when a safe torque level is exceeded. Pneumatic actuators provide for automatic or semi automatic valve operation. They work by translating an instrument air signal into valve stem motion by air pressure acting on a diaphragm or piston connected to the stem. Linear electric valve actuators are well suited for operating in tight tolerances.