How to correctly choose electric valve device

Electric valve electric device is used for operating electric valve and in phase one of the cohesive devices of electric valve. The device driven by electricity, its movement process can be made of stroke, torque or axial thrust intrusive to operate. Because the electric valve electric device depends on the operation characteristics and utilization of electric valve types, equipment operation standard and electric valves on the pipeline or equipment bearing. And grasp the electric valve electric device accurately chosen; Thinking to prevent overload, Operating torque is higher than the control torque) The occurrence of becomes crucial one annulus. Operating torque: operating torque is choosing electric valve electric device of the main parameters. The output torque of electric equipment for electric valve operation maximum moment of 1. 2 to 1. 5 times. Operating thrust: electric valve electric device of the host structure has two kinds, one kind is not equipped with thrust plate, direct output torque at the moment; Another is equipped with a thrust plate, at the moment of output torque after thrust plate of stem nut can be converted into output thrust. Output shaft rolling ring count: the number of laps electric valve electric device output shaft rolling with nominal size of the electric valve, the valve stem thread pitch, thread, according to the M = (H/ZS accounting Type: M for electric equipment should satisfy the total number of rolling ring; H for electric valve opening, mm; S for the stem drive screw pitch, mm; Z to stem thread. ) Stem diameter, stem on multiple inversion electric valves, if pass the largest electric equipment to allow the valve stem diameter can't pass the electric valve stem, cannot assemble electric electric valve. Thus, the inner diameter of the hollow output shaft of electric equipment is necessary than stem electric valve stem diameter. About some reversal non-rising stem of electric valves and reverse electric valve, electric valve, though don't have to think stem diameter after a question, but should also be considered sufficiently when selecting the valve stem diameter and the scale of the keyway, assembling after normal operation. Output speed: electric valve opening and closing speed, easy to produce water hammer. Therefore, should be used according to different conditions, select the appropriate opening and closing speed. Equipment, bridging methods: electric equipment of the method have a vertical, horizontal, ground equipment; Cohesion method is: thrust plate; Stem after ( Rising stem inversion electric valve) ; Non-rising stem inversion; No thrust plate; Stem without; Some reversal of electric equipment use is very wide, is a complete program of electric valve, automatic control and remote control is not short of equipment, mainly used in closed circuit of electric valve. But can't ignore the special requirements of electric valve electric device - — It is necessary to constraint torque and axial force. Electric valve electric device usually adopts constrained torque shafts. When electric equipment standard that determines its manipulation of the torque. Decided in advance, when the time is running, the motor usually do not overload. But as the present status of the following can make its overload: