How to select a control valve?

The control valve consists of two main assemblies: valve body assembly and actuator assembly (or actuator system), which are divided into four series: single seat series regulating valve, double seat series regulating valve, sleeve cylinder series regulating valve and automatic series regulating valve.

• How to select a control valve?

• What are the characteristics of the control valve?

• What are the principles of control valve selection?

How to select a control valve?

There are many types of valve bodies for control valves. Typically used are straight through single seat, through double seat, angle, diaphragm, small flow, tee, eccentric rotation, butterfly, sleeve, ball, etc. When selecting certain options, the following must be taken into account:

1. It is mainly considered according to the selected flow characteristics and unbalance forces.

2. If the liquid medium is a suspension containing a high concentration of abrasive particles, the inner material of the valve should be hard.

3. Since the medium is corrosive, try to choose a valve with simple structure.

4. When the temperature and pressure of the medium is high and the change is large, the valve core and valve seat material should be selected with small temperature and pressure changes.

5. Relaxation evaporation and cavitation occur only in liquid media. In the actual production process, flashing and cavitation create vibrations and noises that shorten the service life of the valve. Therefore, when selecting the valve, overturning and cavitation of the valve should be prevented.

What are the characteristics of the control valve?

1. There are different types of control valves and their application possibilities are different. Therefore, the type of control valve should be wisely selected according to the requirements of the technological production process.

2. Pneumatic control valves are divided into two types: air-on and air-off. The air-to-open control valve is closed in a fault state, and the air-to-close control valve is opened in a fault state. Some accessories can be used to form a retaining valve or make the control valve self-locking, i.e. the control valve maintains the valve opening before failure if the fault occurs.

3. The type of air opening and air closing can be realized by combining positive and negative actuator types and positive and negative valves. When using a valve positioner, this can also be realized by a valve positioner.

4. Different control valves have different structures and have their own characteristics.

What are the principles of control valve selection?

1. Select the appropriate design and material according to the process conditions.

2. Select the flow characteristics of the control valve according to the characteristics of the technological object.

3. Select the appropriate control valve size according to the operating parameters of the process.

4. Select the required accessories according to the requirements of the process.

5. Appropriate selection of implementing organizations. The reaction speed of the actuator should do justice to the process.

Guangzhou HERUI maintains close relationships with customers in the control valve industry and is committed to strengthening production and operation, as well as improving quality and safety.