What is control valve?

The control valve is used to regulate and control the flow, pressure and liquid level of the medium.According to the signal of the adjusting position, the opening degree of the control valve is automatically controlled, so as to achieve the adjustment of the medium flow rate, pressure and liquid level.The control valve is divided into electric control valve, pneumatic control valve and hydraulic control valve.
 
The control valve is composed of electric actuator or pneumatic actuator and control valve.Control valve is usually divided into straight single-seat control valve and straight two-seat control valve, the latter has the characteristics of large circulation capacity, small unbalance and stable operation, so it is usually especially suitable for large flow, high pressure drop and less leakage occasions.
 
Flow capacity Cv is one of the most important parameters to choose the control valve, control valve of flow capacity is defined as: when the control valve fully open, on both ends of the control valve differential pressure is 0.1 MPa, the fluid density is 1 g/cm3, the regulator on the number of traffic flow diameter per hour, called flow capacity, also known as the flow coefficient, expressed as a Cv, unit for t/h, Cv value of the liquid press type calculation.