70 's sleeve valve is widely used in industrial production process control

Eccentric rotary valve (eccentricplugvalve) developed to become the leader of the rotary control valves. The eccentric rotary valve having a good sealing, a large flow capacity, can be applied to a larger pressure difference Occasion. Reform of the 1980s, the birth of a variety of fine small control valve, it controls the valve actuator control valve weight and height decreased ability to increase circulation. The beginning of the 1990s, along with the extensive application of the computer-controlled device, the intelligent control valve is also more and more intense, were born in a variety of intelligent electric valve positioner the fieldbus control valve with a smart valve positioner. 2l century, the the fieldbus control valve has been applied, with the downward movement of the control functions have become more sophisticated, the requirements of the control valve.two position three way valve
Control valves and industrial process control developments. In order to improve the quality of the control of the control system, an integral part of control system composed of a higher requirement. For example, the detection element and the transmitter requirements has higher detection and transmission accuracy, have a faster response and higher stability of the data; control valve actuator requires a smaller dead zone and the friction , have better reproducibility, and shorter response time, and can provide a compensated nonlinear flow characteristics. The same time, due to large-scale industrial production processes and refinement of the control valve also put forward higher requirements.pneumatic auto drain