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2020

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Working principle of self-operated regulating valve

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Self-operated regulating valve, also called self-operated control valve, is a new type of regulating valve. As the name suggests, it does not require external power supply and secondary instruments. It relies on the pressure and temperature of the medium flowing through the valve as energy to drive the valve to work automatically. The feedback signal (pressure, pressure difference, temperature) at the output end of the valve is transmitted to the actuator through the signal tube, which drives the valve disc to change the opening of the valve to achieve the purpose of regulating pressure, flow, and temperature.

Self-operated regulating valve, also called self-operated control valve, is a new type of regulating valve. As the name suggests, it does not require external power supply and secondary instruments. It relies on the pressure and temperature of the medium flowing through the valve as energy to drive the valve to work automatically. The feedback signal (pressure, pressure difference, temperature) at the output end of the valve is transmitted to the actuator through the signal tube, which drives the valve disc to change the opening of the valve to achieve the purpose of regulating pressure, flow, and temperature.

 

According to the structure and function, self-operated regulating valves can generally be divided into: self-operated temperature regulating valves, self-operated pressure regulating valves, self-operated flow regulating valves, etc., which can be applied to most fluid media for automatic regulation. It can effectively convert the self-energy of the fluid medium into driving force to control the opening and closing of the valve.

 

Working principle of self-operated regulating valve:

When the medium fluid flows from the front of the valve and is throttled by the valve core and valve seat, it is converted into pressure behind the valve. Then the upper chamber is input through the pipeline and acts on the top tray. The force generated at this time will be equal to the reaction force of the spring. This determines the relative position of the valve core and valve seat, thereby controlling the pressure behind the valve. When the pressure behind the valve increases, the force acting on the top plate also increases, causing the valve core to close toward the valve seat. In this way, the distance between the valve core and the valve seat decreases, and the flow resistance increases. The pressure behind the valve increases. reduce. Until the force on the top plate is balanced with the reaction force of the spring, the pressure behind the valve drops to the preset value. When the pressure behind the valve decreases, the direction of action is opposite to what was said before. This is the working process of the self-operated regulating valve.

 

For traditional control valves, self-operated regulating valves do not require external energy. They can effectively adjust the properties of the fluid medium by relying only on the output signal of the regulated medium. This not only greatly saves the cost of additional accessories, but also reduces The use of energy caters to the country’s call for energy conservation and emission reduction.