There are two types of electric valve actuators, generally divided into partial-turn electric valve actuators and multi-turn electric valve actuators. The former is mainly used to control valves that require partial rotation, such as ball valves and butterfly valves. The latter is used for valves that require multiple turns of rotation, such as gate valves.

 

The electric multi-turn actuator is one of the most commonly used and reliable types of actuators. It utilizes a single-phase or three-phase motor to drive a gear or worm gear, which in turn drives the valve stem nut. The valve stem nut moves the valve stem, allowing the valve to open or close. Multi-turn electric actuators can quickly drive large-sized valves. To protect the valve from damage, a limit switch at the end of the valve's travel will cut off the motor power. Additionally, when the safety torque is exceeded, the torque sensing device will also cut off the motor power. A position switch is used to indicate the valve's open or closed status. The handwheel mechanism of the device's clutch device allows manual operation of the valve in case of power failure.