HBS relief reducing valves

Pressure control in secondary hydraulic circuits

In hydraulic systems with multiple functions, it is often necessary to operate part of the circuit at a lower pressure than the main system setting. Pressure reducing valves make this possible by supplying a secondary circuit with a controlled, reduced pressure while the main relief valve defines the maximum system pressure.

This approach allows different actuators within the same hydraulic installation to operate safely and efficiently at their required pressure levels.

Operating principle and pressure regulation

These valves are normally open. When the pressure in the secondary branch exceeds the value set by the adjusting spring, a cylindrical spool restricts the oil flow between the main line and the secondary circuit. This controlled restriction reduces the outlet pressure and maintains it at the desired level.

The continuous adjustment of the flow restriction ensures stable pressure control and reliable operation under varying load conditions.

Typical applications and system advantages

Reduced pressure control is commonly required in hydraulic systems with multiple cylinders or functions. Typical applications include mobile machinery and industrial installations where certain components are designed for lower operating pressures.

Key advantages include:

• Independent pressure control in secondary circuits

• Protection of components against excessive pressure

• Increased system flexibility without complex circuit layouts

Pressure reducing valves within the HBS product range

Within the HBS portfolio, pressure reducing valves are designed to integrate seamlessly with other hydraulic components such as relief valves, flow control valves and check valves.

Their robust construction and stable pressure regulation make them suitable for both OEM designs and retrofit solutions in mobile and industrial hydraulic systems.