Product Knowledge | Basic Information on the JW-LOK Pressure Reducing Valve

Release date:

2026-05-20

A pressure-reducing valve is an automatic device that lowers and stabilizes pipeline pressure, widely used in industrial gas systems to ensure safe energy use and reliable equipment operation. By adjusting the throttling area, it reduces the high inlet pressure to the desired outlet pressure and relies on the medium’s own energy to maintain a constant outlet pressure, thereby preventing equipment damage or safety incidents caused by pressure fluctuations.

A pressure-reducing valve is a type of… A valve device that automatically reduces and stabilizes pipeline pressure, widely used in industrial gas systems to ensure energy‑use safety and reliable equipment operation. It reduces the inlet high pressure to the desired outlet pressure by adjusting the throttling area, and relies on the medium’s own energy to maintain a constant outlet pressure, thereby preventing equipment damage or safety incidents caused by pressure fluctuations. 。‌

Working Principle and Key Structural Features of Pressure Reducing Valves

The core design principle of JW-LOK’s Jingwei Valve’s pressure-reducing valve is localized‑resistance throttling combined with automatic feedback control, ensuring that the downstream pressure remains within the set range. ‌

01. Working Principle of the Pressure Reducing Valve

• As the fluid flows through the valve’s flow passage, local resistance is generated by varying the opening of the closing member, thereby reducing the pressure.

• A diaphragm or piston senses changes in outlet pressure: when the pressure exceeds the setpoint, it actuates the valve spool to reduce the flow opening; when the pressure falls below the setpoint, it increases the flow opening, thereby achieving dynamic equilibrium.

02. Key Structure of the Pressure Reducing Valve

• Loading mechanism: It is used to apply a downward load from the top of the pressure-reducing valve, thereby setting the valve’s outlet pressure. The loading mechanism of the JW-LOK pressure-reducing valve is primarily spring‑loaded.

• Sensing mechanism: The thin-film type has high sensitivity (with an error of approximately ±1%); piston-type models are pressure-resistant at high pressures (with an error of approximately ±5%); the spring provides the set-pressure reference.

• Controlling Authority: It can reduce high inlet pressure to a lower outlet pressure by adjusting the flow area of the medium through the vertical movement of the valve spool, thereby maintaining a stable outlet pressure.

• Unbalanced spool: The most common poppet‑type design relies on inlet pressure to provide the primary actuating force, pushing the poppet toward the valve seat. It is highly sensitive to changes in inlet pressure, resulting in a pressure‑supply effect. (SPE) Quite obvious.

• Balance spool : Through a specialized structural design, the contribution of inlet pressure to the loading force has been reduced, resulting in a pressure‑supply effect. (SPE) is less pronounced than the unbalanced spool. As shown in Figure 3, the design of the balance port is a key distinguishing feature between the two spools.

• Self-discharge: One of the characteristics of a pressure-reducing valve is that, by adding a passage that runs through the sensing mechanism, when rotated in the counterclockwise direction… (DECREASE) Rotate the pressure‑regulating knob to fully relieve outlet pressure in a closed system via its self‑draining design—no additional purge or relief valves are required.

• Capture emissions: One of the features of a pressure-reducing valve is that it typically incorporates a port in the valve bonnet, allowing users to vent any leaked medium to a designated location in the event of a seal failure in the sensing mechanism.

JW-LOK Product Specifications

JW-LOK Jingwei Valve’s pressure-reducing valves are primarily categorized into the following five types, depending on the medium and application scenario:

01. Product Features