1. Product Overview

The self-operated control valve requires no external energy supply. It utilizes the inherent energy of the process medium as the power source to drive the actuator, adjust the plug position, and change the pressure difference and flow rate across the valve. This stabilizes the upstream or downstream pressure of the valve automatically.

Featuring sensitive response, reliable tight sealing and minor fluctuation of pressure set point, this valve is widely applied in automatic pressure regulation for gas, liquid and steam media, including pressure reduction, pressure stabilization and pressure relief stabilization working conditions.

This series of valves offers two working types: Type B (downstream pressure regulation for pressure reduction) and Type K (upstream pressure regulation for pressure relief). The adjustable pressure range covers 15~250KPa with segmented regulation, and flexible combinations are available to meet diverse on-site working conditions.

2. Working Principle

The self-operated control valve relies on the medium’s own pressure to adjust the valve opening and realize automatic flow regulation. It is mainly composed of a valve body, valve plug, valve seat, spring and other core components. When the medium flows into the valve, the medium pressure acts on the valve plug, overcomes the spring force and drives the plug to move, thereby changing the valve opening degree.

After setting the target flow value according to process requirements, the valve will automatically adjust the plug position once the actual flow deviates from the set value, keeping the actual flow consistent with the preset parameter. It boasts prominent advantages of no external energy required, fast response speed and high control accuracy.

3. Flow Control Mode

Self-acting control valves are divided into two control types: direct-acting and indirect-acting.

Direct-acting Type: Adjusts the valve opening directly by the self-pressure of the process medium, realizing passive automatic regulation without auxiliary equipment.

Indirect-acting Type: Matches with an external control system to drive valve operation and achieve precise automatic flow regulation.

Both control modes support fast and accurate flow control to stabilize process parameters.

In practical industrial applications, the valve can cooperate with sensors and controllers. Sensors detect real-time medium parameters such as flow and pressure and transmit signals to the controller. The controller outputs control signals according to the deviation between set values and actual values to adjust the valve plug position, realizing closed-loop automatic regulation, stabilizing production process parameters and improving production efficiency and product quality.

4. Standard Specifications