FIG680 stainless steel three way and two way control valve

Technical parameter
Installation dimensions
Model description
Working Principle
Technical parameter

Installation dimensions

Model description

Working Principle
 Working principle of pneumatic control valvePneumatic control valve drives itself by compressed air as power source , cylinder as actuator and with some attachments ,such as electric-pneumatic positioned、converter、 solenoid valve、lock up valve and so on. It realizes the switch quantity or proportional adjustment, and receives the control signal of industrial automation control system to complete regulating the flow 、pressure 、temperature and other various process parameters of pipeline medium. Pneumatic control valve has characteristics of simple controlling, quick response, and intrinsically safe without additional explosion prevention measure.So sometimes, Air to open type is also called Fail to Close/ FC type. Air to close type‘s movement direction is just the reverse of Air to open type. When the air pressure increases, valve moves in the direction of closing; when air pressure decreases or disappears, valve moves in the direction of opening or until fully open. So sometimes it’s called Fail to Open /FO. Pneumatic control valve belongs to which type is according to positive and negative effects of the actuator and different assemble ways of valve structure.For example, a heating furnace combustion control, the control valve is installed in the fuel pipe, according to the temperature of furnace or the heated material in furnace exit to control the supply of fuel. At this time, Air to open type valve is safer, because once stop the air supply, It’s more suitable in closed position than in fully open position for valve.Valve positioner is the main accessory of control valve, it accepts the regulator output signal, and then controls the pneumatic control valve by its output signal, when control valve moves, the displacement of valve stem feedback to valve positioner through mechanical device, valve position condition will be sent o the upper system through the electrical signal .      Valve positioner can increase the output power of control valve, reduce the transmission lag of control signal, speed up movement of valve stem, improve the linearity of valve, overcome the friction of valve stem and eliminate the influence of unbalanced force, so as to ensure positioning rightly.      Actuator has pneumatic actuator, electric actuator, straight stroke and stroke.