HBD – Hydraulic Pressure Reducing Valve

What is a Hydraulic Pressure Reducing Valve?

A hydraulic pressure reducing valve is a type of control valve used to regulate and reduce the pressure in a specific section of a hydraulic system. It is typically used when a certain part of the hydraulic circuit requires lower pressure, providing a controlled outlet pressure independently from the main pump pressure (main line).

Working Principle

Hydraulic pressure reducing valves are generally composed of key components such as a spring, piston, and spool. The working mechanism operates as follows:

Inlet Pressure (P1):

Hydraulic oil enters the valve at high pressure.

Pressure Balancing:

The spring-loaded spool opens up to the set pressure, allowing flow through the valve.

If the outlet pressure increases, the spool moves forward, reducing the opening.

Thus, the outlet pressure (P2) is kept constant.

Drain Channel:

Excess oil is directed to the tank via the drain line.

These valves can be either proportional (pilot-controlled) or direct-acting , depending on the design.

Types of Pressure Reducing Valves

Direct-Acting Pressure Reducing Valve:

• Basic models operated by spring force.
• Used in systems requiring more precise and faster response.
• Suitable for low-flow applications.

Pilot-Controlled Pressure Reducing Valve:

• The main spool is controlled by a pilot valve.
• Used in systems where higher flow and accurate pressure control are required.
• Provides more stable pressure under sudden load changes.

Application Areas

• Hydraulic machines (presses, injection molding machines)
• Mobile hydraulic systems (construction equipment, cranes)
• Industrial automation systems
• Hydraulic circuits requiring precise motion control

Advantages

✔ Enables different pressure levels at specific points in the hydraulic circuit
✔ Prevents sudden pressure fluctuations, protecting equipment
✔ Saves energy by reducing unnecessary high pressure and lowering power consumption

Important Considerations

• Pressure adjustment must be done correctly; otherwise, system performance may decrease.
• The drain line should be properly designed; otherwise, un-drained oil may cause temperature rise.
• Sensitive to contamination; clean hydraulic oil must be used.

Based on the technical information above, when selecting the right type of valve for your system, you should consider your pressure requirements, flow needs, and load variations within your system.

For detailed technical information and pricing on Hidrofix brand hydraulic pressure reducing valves , please contact our technical sales engineers through our official communication channels.