There are many control valve types, the popular ones are pneumatic film angle control valve,electric single seat control valve, electric sleeve control valve, cage sleeve control valve, pneumatic diaphragm control valve etc.
3. If the medium is corrosive, try to choose a valve with a simple structure.
4. When the temperature and pressure of the medium are high and the change is large, the valve core and valve seat material should be selected with small changes in temperature and pressure.
1. It is mainly considered according to the flow characteristics and unbalanced forces.
2. When the fluid medium is a suspension containing a high concentration of abrasive particles, the internal material of the valve should be strong enough.
In order to make the control valve works better, the matching actuator must be able to generate enough output force to ensure a high degree of sealing and the opening of the valve.
For double-acting pneumatic, hydraulic, and electric actuators, there is generally no return spring. The magnitude of the force has nothing to do with its running direction.
Therefore, the key to choosing an actuator is to find out the maximum output force and the torque of the motor.
For single-acting pneumatic actuators, the output force is related to the opening of the valve, and the force on the control valve will also affect the motion characteristics, so it is required to establish a force balance over the entire opening range of the control valve.
After determining the output force of the actuator, select the corresponding actuator according to the requirements of the process use environment.
When there are explosion-proof requirements on site, pneumatic actuators should be selected. From the perspective of energy saving, electric actuators should be selected as far as possible.
If the adjustment accuracy is high, the hydraulic actuator can be selected. Such as speed regulation of turbines in power plants, temperature regulation and control of catalytic reactors in oil refineries, etc.
The control valves are widely used in different fluids like water, oil, chemicals, etc.