How to choose electric butterfly valve

Stem diameter: on the rotary rod similar to the class. It can not be assembled into an electric valve. Therefore, the maximum valve stem diameter allowed by the electric butterfly valve assembly can not pass through the valve stem of the valve. Electric hollow output shaft diameter must be greater than the stem rod valve stem diameter. The partial rotary valve and the multi-turn valve in the dark rod valve, though not considered the passage of the stem diameter, but should also fully consider the stem diameter and keyway size, so that the assembly work properly. Operating torque: Operating torque is the choice of the most important parameters of the valve electric device. Electric butterfly valve movement process by the stroke, torque or axial thrust to control the size. Because the working characteristics and utilization rate of the valve electric device depend on the type of the valve, the working specifications of the device and the position of the valve on the pipeline or equipment, the valve electric butterfly valve device is an indispensable device for program control, automatic control and remote control of the valve. Therefore, the correct choice of valve electric device, to prevent the occurrence of overload (working torque is higher than the control torque) is essential. In general, the correct choice of valve electric butterfly valve device basis. Electric device output torque should be 1.21.5 times the maximum torque of the valve operation. Electric butterfly valve operation thrust: There are two kinds of host structure of the valve electric device: one is not configured thrust plate. The output torque is converted to output thrust by the stem nut in the thrust plate. Direct output torque; the other is to configure the thrust plate. Number of rotation of the output shaft: The number of valve motor driven output shaft rotation and the nominal diameter of the valve stem pitch, the number of threads related. H is the valve opening height, to be calculated as M = HZS (M is the total number of rotations that the electric device should satisfy. S is the stem thread pitch, Z is the stem thread number.