The difference and selection of electric control valve and pneumatic control valve

With the rapid development of industrial automation in our country, the control valve has been widely used, mainly used to regulate the flow, pressure and level of the medium parameters, plays a very important role! The regulating valve is composed of two parts, the actuator and the valve, which can be divided into electric control valve, pneumatic control valve and self regulating valve. So, as the most commonly used electric control valve and pneumatic control valve, and how to distinguish and choose it?

As the name suggests, the biggest difference between them is that one is controlled by power supply, and the other is controlled by gas source! The electric control valve uses the motor to do the power, and the pneumatic control valve uses the compressed air to make the power. Fundamentally, it doesn't make much difference, but the drive is not the same! Electric control valve is the basic error and the sensitivity reached 0.3%, not in the other set source is not suitable for explosion-proof requirements high occasions. Pneumatic control valve and its basic error and sensitivity of 0.5%, but also the establishment of gas station, but its intrinsic safety. It is suitable for occasions requiring high explosion protection.

Selection of electric control valve and pneumatic control valve:

1, from the price: the price of pneumatic control valve will be cheaper than electric, economical, only need gas source as power!

2, from applications: pneumatic valve need to configure the compressor and other equipment, the advantage is itself has the function of explosion-proof, and simple maintenance, low failure rate, so in the chemical, petrochemical and other industries, the use range is much larger than the electric control valve.

3, from the running time: pneumatic control valve action is relatively faster, but the need for stable gas source, and the electric control valve will be relatively slow!

4, the electric control valve control precision is high, can use electricity, can bring a variety of related functions.

5, pneumatic control valve precision is low, the need for gas supply equipment, the need for signal conversion accessories.

6, electric control valve is mainly used in power plants or nuclear power plants, because in the high-pressure water system needs a smooth, stable and slow process.

Advantages and disadvantages of electric control valve and pneumatic control valve:

(1) the advantages of electric control valve: liquid medium and large diameter gas effect is good, not affected by the climate. Not affected by the pressure of air compressor. Disadvantages: high cost, bad in humid environment.

(2) pneumatic control valve advantages: the gas medium and small diameter liquid effect is good, low cost, convenient maintenance. Disadvantages: affected by the fluctuation of air compressor pressure, it is easy to be affected by air compressor water in the northern winter, causing the transmission part to freeze and not move.

In summary, the difference between the two is a power, a gas, from the selection, the user should consider the issue, according to the installation position, there is no gas or power supply, switching speed, to select the appropriate type of valve.