In piping engineering, the correct selection of electric valves is one of the guarantee conditions to meet the use requirements. If the electric valve used is not properly selected, it will not only affect the use but also bring adverse consequences or serious losses. Electric valve suppliers to answer your question about how to use the electric valve correctly.
An electric valve is simply a valve that is controlled by an electric actuator to open and close the valve. It can be divided into two parts, the upper half is the electric actuator, and the lower half is the valve. It can also be called an air conditioning valve.
1.the operating torque is the main parameter for selecting the valve electric device, the output torque of the electric device should be 1.2 ~ 1.5 times the maximum torque of the valve operation.
There are two main structures of the electric device for operating the thrust valve: one is not configured with a thrust disk, directly output torque; the other is configured with a thrust disk, the output torque is converted to output thrust through the thrust disk in the stem nut.
3.the number of output shaft rotating revolutions of the electric device output shaft of the valve is related to the nominal diameter of the valve, the stem pitch, the number of threaded head, and is calculated according to M = H / ZS (M is the total number of rotating revolutions that the electric device should meet, H is the valve opening height, S is the stem drive thread pitch, Z is the number of stems threaded head).
4. the stem diameter of multi-turn open stem valves, if the electric device allows the maximum stem diameter can not pass the valve stem of the matching valve, it can not be assembled into an electric valve. Therefore, the inner diameter of the hollow output shaft of the electric device must be greater than the outer diameter of the stem of the open stem valve. For some of the rotary valves as well as multi-turn valves in the dark rod valves, although the stem diameter through the problem should not be considered, the stem diameter and the size of the keyway should be fully considered in the matching, so that the assembly can work normally.
5. the output speed of the valve opening and closing speed is too fast, easy to produce water shock. Therefore, the appropriate opening and closing speed should be selected according to different use conditions.
6.the valve electric device has its own special requirements, which must be able to limit the torque or axial force. Usually, the valve electric device uses torque limiting couplings. When the electric device specifications are determined, the control torque will be determined.