Electric actuators are important control devices. There are three types of electric actuators. The electric actuators are available in straight stroke, angular stroke and multi-turn type. The angular-stroke electric actuator uses a motor as a power component to convert the input DC current signal into a corresponding angular displacement (0 degrees to 90 degrees). This actuator is suitable for operating rotary control valves such as butterfly valves and baffles. The straight-stroke actuator receives the input DC current signal and then rotates the motor, then decelerates through the reducer and converts it into a linear displacement output to operate various control valves such as single-seat, two-seat, and three-way, and other linear control mechanisms.
The multi-turn electric actuator is mainly used to open and close the multi-turn valve such as the gate valve and the stop valve. Because of its relatively large motor power, the maximum is tens of kilowatts, which is generally used for local operation and remote control. These three types of actuators are position servos powered by two-phase AC motors. The three electrical principles are identical, except that the reducers are different.