Pneumatic Control Valve

Standard: API, DIN, JIS, GB. 
Material: Stainless Steel, Carbon Steel, Alloy Steel, Titanium, 904l, Cast Steel.  
Size: 1/2"~18", DN15~DN400.
Pressure: 150LB-2500LB, PN10~PN420.
Type: Globe Type, Double Seat, Single Seat, V Port, Ball Type, V Ball, Cage, Angle Type, 3 Way, Self Opreated, Pressure, Tempreature, High Tempreature, Power Station, Cv3000, Flanged, Cryogenic, Low Tempreature, Moterized, Pneumatic.

Control valves are valves accustomed to control conditions for example flow, pressure, temperature, and liquid level by fully or partly opening or closing as a result of signals caused by controllers that compare a "setpoint" to a "process variable" whose value is supplied by sensors that monitor alterations in such conditions.The outlet or closing of control valves is generally done instantly by electrical, hydraulic or pneumatic actuators. Positioners are utilized to control the outlet or closing from the actuator according to electric, or pneumatic signals. These control signals, typically according to 3-15psi (.2-1.0bar), more prevalent now are 4-20mA signals for industry, -10V for Heating and cooling systems, and the development of "Smart" systems, HART, Fieldbus Foundation, and Profibus to be the more prevalent protocols.
 
A pneumatic control valve includes three primary parts by which each part appear in several types and fashions : Valve's actuator, Valve's positioner, Valve's body.