Jan. 13, 2021
Control valves are divided into three categories: pneumatic, electric and hydraulic, depending on the energy used by the actuator.First of all, whether it is pneumatic control valves, electric control valves or hydraulic control valves, their regulating mechanism is similar, the difference lies in their implementation structure above.Electric control valve supplier will explain the difference between electric control valves and pneumatic control valves in what
Pneumatic control valves are powered by compressed air, with the advantages of simple structure, reliable and stable action, high output force, easy maintenance and fire and explosion-proof. So it is widely used in petroleum, chemical, metallurgy, electric power and other sectors, especially for petroleum and chemical production processes with the risk of explosion. Its disadvantage is that the hysteresis is large, not suitable for remote transmission (within 150m), and can not be connected with digital devices.
Electric control valves are powered by electricity, which is characterized by easy access to energy, fast action, fast signal transmission speed, and can be transmitted over long distances, easy to use with digital devices, etc.. So the electric control valve is in the development and rise period, is a promising device. Its disadvantages are complex structure, expensive and small propulsion force, at the same time, generally speaking, electric control valves are not suitable for fire and explosion-proof occasions. However, if the explosion-proof structure is used, it can also meet the requirements of fire and explosion-proof.
At present, the control valves selected at home and abroad, the liquid-operated few.
The biggest difference is that one uses electricity and one uses gas!
I. Electric control valves use electric motors for power, pneumatic control valves use compressed air for power.
(1) the advantages of electric control valves: good effect on liquid media and large diameter gas, not affected by climate. Not affected by the pressure of air pressure gas. Disadvantages: high cost, in a humid environment is not good.
(2) Pneumatic control valve advantages: good for gas media and small diameter liquid, low cost, easy maintenance. Disadvantages: affected by fluctuations in the pressure of the air pressure gas, in the northern winter easily affected by the air pressure gas containing water, causing the transmission part to freeze and not act.
II. General pneumatic control valves are faster than electric control valves, electric are dual-use hand and electricity. And pneumatic to hand, gas dual-use price is relatively high.
Three. Electric control valves are used in some large pipe diameter, because pneumatic control valves are difficult to do, but the stability of electric control valves are not as stable as pneumatic, slow switching speed, the actuator will be stuck teeth for a long time. Pneumatic control valve switch speed, high precision, but requires a stable gas source.