Definition and basic functions

The pressure reducing valve OV is a control valve for reducing the pressure of a fluid (gas or liquid). Its main function is to adjust the high-pressure fluid at the inlet to a lower and stable pressure at the outlet to meet the pressure requirements of downstream equipment or systems and ensure that the system operates under safe and stable pressure conditions.

Structural features

Valve body structure: Valve body is the main shell of the valve OV, generally made of metal materials, such as cast steel, stainless steel, etc., to ensure sufficient strength and corrosion resistance. Its shape is diverse, common spherical, cylindrical and so on. The valve body contains fluid channels, which are designed to be optimized for different pressure reduction requirements and flow characteristics. For example, in some high-flow decompression applications, the internal passage of the valve body will be designed to be more spacious to reduce fluid resistance.

Spool and Seat: The spool is a key component to control the decompression process. It moves up and down or rotates in the valve body to adjust the area through which the fluid passes. The valve seat is closely matched with the valve core to form a sealing surface. The material of the valve core and valve seat is usually made of wear-resistant and corrosion-resistant materials, such as hard alloy or special engineering plastics. In the high-precision pressure reducing valve OV, the processing accuracy of the valve core and valve seat is very high to ensure good sealing and precise pressure adjustment. For example, in the case of a gas pressure reducing valve, a small sealing surface leak may result in inaccurate pressure control.

Adjustment mechanism: The pressure relief valve OV is equipped with an adjustment mechanism for setting and adjusting the outlet pressure. This mechanism can be manual, such as by rotating the hand wheel to adjust the position of the spool; it can also be electric or pneumatic, through the external signal to control the movement of the spool. The manual adjustment mechanism is simple and reliable, and is often used in occasions where the pressure requirements are relatively fixed; the electric or pneumatic adjustment mechanism is more suitable for remote control or dynamic adjustment of the pressure according to the system working conditions.

Working principle

When high pressure fluid enters the pressure relief valve OV from the inlet, the fluid acts on the spool. As the fluid pressure changes, the valve core operates according to the pressure value set by the preset adjusting mechanism. If the inlet pressure increases, the spool will move accordingly, reducing the cross-sectional area through which the fluid passes. According to the principle of fluid mechanics, when the fluid passes through a smaller cross-sectional area, the pressure will decrease, resulting in a lower pressure at the outlet. For example, for a liquid pressure reducing valve, when the inlet pressure increases, the spool will move upward (assuming a vertically moving spool), narrowing the passage through which the liquid passes, increasing the liquid flow rate and decreasing the static pressure, thereby achieving decompression.

The pressure relief valve OV is usually also provided with a pressure feedback mechanism. The pressure at the outlet acts on the other side of the spool through the feedback channel, and is balanced with the inlet pressure and the setting force of the adjustment mechanism. When the outlet pressure reaches the set value, the spool will stabilize in a position to maintain the stability of the outlet pressure. This feedback mechanism can effectively resist the influence of inlet pressure fluctuation and flow change on outlet pressure, and ensure the stability of outlet pressure.

Application areas

Industrial Piping Systems: Pressure reducing valve OV is widely used in pipeline transportation systems of chemical, petroleum and natural gas industries. For example, in chemical production, the fluid from the high-pressure reactor may need to be decompressed before it can enter the subsequent processing or storage equipment to avoid excessive pressure damage to the equipment.

Water supply system: In urban water supply systems, pressure relief valves OV are used to reduce the higher pressure of the municipal water supply to a pressure suitable for household and building use. For example, in the water supply system of high-rise residential buildings, the pressure reducing valve OV is installed on the branch pipes of each floor, and the high-pressure water in the riser is reduced and supplied to the user, so as to prevent the faucet, toilet and other water appliances from being damaged due to high pressure.

Pneumatic system: In the pneumatic equipment of the factory, such as pneumatic tools, pneumatic actuators of automatic production lines, etc., the pressure reducing valve OV is used to decompress the high-pressure gas from the air compressor to the appropriate working pressure. This can ensure the safe operation of pneumatic equipment, but also improve the service life of the equipment, because too high air pressure may cause damage to pneumatic components.