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Self-acting pressure control valves do not require any external energy sources such as power or air; they are driven by the energy of the fluid itself. This makes them energy-efficient and environmentally friendly, and they are easy to use – once the pressure value is set after installation, they can operate automatically. As a result, they are increasingly used in situations where high control precision is not required, and where access to power or air sources is limited. However, during use, it is essential to pay attention to the specific requirements of the selection; otherwise, accidents are likely to occur. During use, attention should be paid to the selection of the valve and the installation environment; therefore, it is very important to have a thorough understanding of the working principle and structure of self-acting pressure control valves. 1. Purpose and scope of application: The self-acting pressure control valve (hereinafter referred to as pressure valve) is an energy-saving device that requires no external power source; it relies solely on changes in the pressure of the fluid itself to automatically regulate pressure. It has comprehensive functions of measurement, execution, and control. It is widely applicable to industrial sectors such as petroleum, chemicals, metallurgy, and light industry, as well as to urban heating and steam supply systems. This product can be used in pressure control devices for non-corrosive media such as liquids, gases, and vapors (up to a maximum temperature of 350°C). 2. Structure and working principle: The pressure Pl of the process medium in front of the valve is reduced through throttling by the valve core and seat, resulting in the pressure P2 behind the valve. P2 is then sent via control lines to the lower diaphragm chamber of the actuator, where it exerts force on the top plate. The resulting force is balanced by the reaction force of the spring. It determines the relative position of the valve core and the valve seat. Pressure behind the control valve. When the pressure behind the valve P2 increases. The force exerted by P2 on the top plate also increases accordingly. At this time. The force exerted by the top plate is greater than the reaction force of the spring. Moves the valve core to the position where it closes against the valve seat. Until the force exerted by the top plate is balanced by the spring reaction force. At this time. The flow area between the valve core and the valve seat decreases. The flow resistance increases. Thereby reducing P2 to the set value. Similarly, when the pressure behind the valve P2 decreases. The direction of action is the opposite of the above. This is the working principle behind pressure regulation after the valve. When it is necessary to change the set value of the pressure P2 behind the valve. Adjustable adjusting nut 8.3. Technical features: A self-acting pressure control valve is an actuator that requires no external power source; it achieves automatic regulation by utilizing the energy of the medium being controlled. The biggest advantage of this product is its ability to operate in environments without electricity or gas, while also saving energy; the pressure setting can be adjusted at will during operation. It features a quick-opening flow characteristic, offering rapid response and excellent sealing performance; as a result, it is widely used in various industrial devices across sectors such as petroleum, chemicals, power generation, metallurgy, food processing, textiles, machinery manufacturing, and residential buildings for the automatic control of pressure reduction, pressure stabilization (for regulation after the valve), or pressure relief and pressure maintenance (for regulation before the valve) of gases, liquids, and steam media. The attached condenser can be used at temperatures ≤350°C.