pneumatic control valve, with compressed air as the power source, cylinder as the actuator, and with the help of electrical valve positioner, converter, solenoid valve, holding valve and other accessories to drive the valve, realize the switching value or proportional regulation, receive the control signal of industrial automation control system to complete the regulation of pipeline medium: flow, pressure, temperature and other process parameters. It is characterized by simple control, fast reaction and intrinsic safety, and no need to take additional explosion-proof measures. It is one of the industrial process control instruments widely used in petroleum, chemical, electric power, metallurgy and other industrial enterprises.

 

   the electric control valve is composed of the electric actuator and the control valve after mechanical connection, assembly, commissioning and installation. It is an important execution unit instrument in industrial automation process control. With the increasing degree of automation in the industrial field, it is more and more applied in various industrial production fields. Compared with the traditional pneumatic control valve, it has obvious advantages: the electric control valve is energy-saving (only consumes electric energy when working), environmental protection (no carbon emission), quick and convenient installation (no need for complex pneumatic pipeline and air pump workstation). It is in the field of electric power, chemical industry, metallurgy, environmental protection, water treatment, light industry, building materials and other industrial automation system.

 

   hydraulic control valve is used to change the channel section and medium flow direction, with the functions of diversion, cut-off, regulation, throttling, check, shunt or overflow pressure relief. The valves used for fluid control range from the simplest stop valve to various valves used in extremely complex automatic control system, with various varieties and specifications. The nominal diameter of the valves ranges from very small instrument valves to industrial pipeline valves with a diameter of 10m. The valve can be used to control the flow of water, steam, oil, gas, mud, various corrosive media, liquid metal, radioactive fluid and other types of fluid, Such as manual, electric, hydraulic, pneumatic, worm gear, electromagnetic, electromagnetic - hydraulic, electric - hydraulic, pneumatic - hydraulic, spur gear, bevel gear drive, etc.; under the action of pressure, temperature or other forms of sensing signal, The valve operates according to the predetermined requirements, or simply opens or closes without depending on the sensing signal. The valve relies on the driving or automatic mechanism to make the lifting, sliding, swinging or rotary movement of the opening and closing parts, so as to change the size of its flow channel area to realize its control function.

 

   self operated control valve uses the feedback signal (pressure, differential pressure and temperature) from the valve output end to the actuator through the signal pipe to drive the valve disc to change the opening of the valve, so as to achieve the purpose of regulating pressure, flow and temperature. Depending on the pressure and temperature of the medium flowing through the valve as energy, the valve can work automatically without external power supply and secondary instrument. It is divided into three series of self operated pressure, differential pressure and flow control valves. The self operated pressure regulating valve can be divided into two types according to the position of pressure taking point: before and after the valve. When the pressure taking point is in front of the valve, it is used to regulate the constant pressure in front of the valve; when the pressure taking point is behind the valve, it is used to regulate the constant pressure behind the valve. When the pressure before and after the valve is introduced to both sides of the air chamber of the actuator at the same time, the self operated differential pressure regulating valve can adjust the pressure at both ends of the regulating valve to be constant, or the pressure difference at both ends of the orifice plate installed on the pipeline can be introduced to both sides of the air chamber of the membrane actuator to form the self operated flow regulating valve, or the flow can be adjusted by the self operated differential pressure regulating valve after flow detection in other ways. Widely used in petroleum, chemical, electric power, metallurgy, food, textile and other industrial equipment gas, liquid, steam medium decompression, pressure relief, pressure stabilization.