Weak current College】 【valve electric device selection method.

Because electric valve is a valve and actuator combination, so when the valve is to determine how to properly select, after the electronic device is related to the actual use of the ability to meet project needs. When you select electric device not only consider the foregoing work environment, electrical control and general technical performance, but also for electric appliance integrated technology performance should be fully taken into account.

1. electric device output torque and speed

Output torque value is the electric device of one of the important technical parameters, and also the use will need to select the important parameters. If you assembled electric valve selection of electric appliance when output torque is too large or less are not desirable. Because of General Electric appliance factory in the factory are required output torque value of testing and adjustment, is relatively accurate. If you choose to use very large output torque margin will make electric valve has a great potential danger in the event of failure to control protection will easily cause damage to the valve (valve stem, valve rupture) phenomenon, it is easy to result pipeline system. So the output torque margin choose too large is not desirable. If you are in practice not open valves belong to select is not reasonable.

On the electric device output speed determines, at the time of its opening and closing the valve is not strictly required, you should try to choose a slow speed.

Because unnecessary more speed, in the same torque demand will increase the motor power, this will not only a waste of energy, increasing construction costs, but also makes the electric device volume increase which resulted in many aspects of the waste.

Currently the self-developed electric appliance, in each frame size in design with the motor specification number (generally 2-3), as well as the main driving gears and worm changes the range of speed ratio is limited, so each frame size of torque tranche and speed are not numerous. tranche

2, electric appliance maximum thrust value allowed

If the valve axial force commitment by electric appliance (stem nut in electric appliance), its thrust values do not allow more than the allowed values for electric installations.

3. the valve stem nut of the number of maximum circling

In the selection of multi-turn valve electric device must indicate when the valve stem nut of the number of maximum spinning around, so you can correctly matching electric device position indication in the institution of the gear ratio, so that location indicates sufficient precision meets valve work on the valve to open and close degree of observation, easy impression, affecting its normal work.

4, the valve stem diameter of allowed values

Lifting the valve selection electric device should be aware of its allowed values through the valve stem diameter, the diameter of the stem must be less than the value. Additionally, for multi-turn electric actuator, the selection should also cover the stem height requirements (and the valve diameter for pain). Rotary valve is equipped with the valve cover.

5, valve and actuator connection

Valve and actuator connection type and size should be consistent with the national standard: GB/T12222-1989 multi-turn valve drive connections, GB/T12223-1989 part of rotary valves driven devices connection.

Currently, the part of the rotary valve electric device with mechanical limit to prevent cannot determine disc location, such valves and electric appliances connect screw and keyway position correspond to the requirements strictly.