A. Operating torque
The operating torque is the most important parameter for selecting the butterfly valve electric actuator. The output torque of the electric actuator should be 1.2~1.5 times the maximum operating torque of the butterfly valve.
B. Operating thrust
There are two main structures of the butterfly valve electric actuator: one is not equipped with a thrust plate, and the torque is directly output; the other is equipped with a thrust plate, and the output torque is converted into an output thrust through the valve stem nut in the thrust plate.
C. The number of turns of the output shaft
The number of turns of the output shaft of the valve electric actuator is related to the nominal diameter of the valve, the pitch of the valve stem, and the number of threaded heads. It should be calculated according to M=H/ZS (M is the total number of turns that the electric device should meet, and H is the Valve opening height, S is the thread pitch of the valve stem drive, Z is the number of stem thread heads).
D. Stem diameter
For multi-turn rising stem valves, if the maximum stem diameter allowed by the electric actuator cannot pass through the stem of the equipped valve, it cannot be assembled into an electric valve. Therefore, the inner diameter of the hollow output shaft of the electric device must be larger than the outer diameter of the valve stem of the rising stem valve. For part-turn valves and dark-stem valves in multi-turn valves, although there is no need to consider the passage of the diameter of the valve stem, the diameter of the valve stem and the size of the keyway should also be fully considered when selecting, so that the valve can work normally after assembly.
E. Output speed
If the opening and closing speed of the butterfly valve is too fast, it is easy to produce water hammer. Therefore, the appropriate opening and closing speed should be selected according to different use conditions.
Post time: Jun-23-2022
