How to choose the electric actuator matched with the valve

Update:20-05-2020
Summary:

Electric actuators are mostly matched with valves and u […]

Electric actuators are mostly matched with valves and used in automatic control systems. There are many types of electric actuators, and there are different ways of movement. For example, an electric actuator with an angular stroke outputs an angular torque, while an electric actuator with a straight stroke outputs a displacement thrust. The type of electric actuator used in the system should be selected according to the working needs of the valve.

The types of valves themselves are quite diverse, and the uses and working principles of various valves are also different, but generally the valves are controlled by turning the flap angle or lifting the valve plate to control the opening and closing or opening and closing angles. The selection of electric imported actuators should be matched according to the opening and closing methods of imported valves.

1. Angular stroke electric actuator

Angle stroke electric actuators are used in conjunction with rotary valves. The rotation of the output shaft of the angular stroke electric actuator is less than one cycle, that is, 360 degrees. For example, the rotation angle of the butterfly valve, ball valve and plug valve is usually less than 90 degrees. The rotation of the angular stroke electric actuator at 90 degrees can realize the opening and closing process of the valve.

Angle-stroke electric actuators are divided into two types: direct-connected electric actuators and base crank-type electric actuators according to the installation interface method. The output shaft of the direct-connected electric actuator is directly connected to the valve stem, while the base crank-type electric actuator is connected to the valve stem through the crank.

2. Multi-turn electric actuator

Multi-turn electric actuator is also an electric actuator that outputs angular torque. The difference between it and angular stroke electric actuator is that its output shaft rotates more than 360 degrees. Multi-turn electric actuators are suitable for rotary valves with multiple rotations to complete the opening and closing process, such as gate valves and globe valves.

3. Straight travel electric actuator

The output of the straight-stroke electric actuator is displacement thrust, which is suitable for the valve type of valve flap lifting control, such as single-seat control valve and double-seat control valve.