Proportional pressure reducing valves precisely regulate the pressure in hydraulic systems – consumers receive exactly the pressure they need. This ensures that applications operate reliably and with low wear, even at high pressures in the main circuit.

A pressure reducing valve lowers the system pressure in the partial circuit and keeps it constant. This protects components, increases process stability, and improves the efficiency of the overall system.

In the proportional version, the function goes one step further. The pressure downstream of the valve is not set mechanically but is controlled by an electrical signal. This allows for continuous adjustment – dynamically, precisely, and in real time. This is indispensable, especially in applications with variable loads.

Whether in mechanical engineering, mobile machinery, or test benches, proportional pressure reducing valves create the basis for precise movements, reproducible processes, and a long service life for hydraulic components. ARGO-HYTOS offers a wide range of products for this purpose, from compact direct-acting variants to powerful pilot-operated valves with integrated electronics.

What is the function of pressure reducing valves in hydraulics?

Pressure reducing valves regulate the pressure in a section of a hydraulic system to a defined value. They thus ensure the supply to consumers that may only be operated at reduced pressure.

While pumps and main circuits are often designed for high pressure levels, cylinders, motors, or control blocks often require lower values in order to operate reliably and with low wear. Without this control, overloads would occur that would damage components and jeopardize the stability of the system.

A classic pressure reducing valve works mechanically by throttling or shutting off the oil flow when the set pressure is reached. In the proportional version, this function is enhanced by an electrical input signal. The output pressure adjusts continuously depending on the signal strength. This allows pressures to be flexibly and dynamically adjusted to changing load situations.

This technology is used in particular in mechanical engineering, mobile machinery, test benches, and proportional hydraulics. Typical applications include clutch controls, clamping systems, and consumers with variable pressure requirements. Proportional pressure reducing valves increase the service life of sensitive components, improve process quality, and contribute significantly to the energy efficiency of modern hydraulic systems.

What is the difference between direct-acting and pilot-operated pressure reducing valves?

Directly controlled proportional pressure reducing valves have a simple design. The electromagnet acts directly on the valve cone or slide. The electrical input signal determines the magnetic force, which in turn influences the opening of the valve. The advantages of this design are its fast response and compact construction, which are particularly impressive for small and medium volume flows. The limitation lies in the flow capacity, which is restricted as requirements increase.

Pilot-operated valves, on the other hand, consist of a pilot stage and a main stage. The pilot stage controls the control pressure that moves the main piston. This allows larger volume flows to be regulated and greater accuracy to be achieved. Due to their more complex design, they are ideal for demanding applications with high performance requirements. Both valve types are available in versions with external control electronics or with integrated electronics.

The plug-and-play solution integrates signal processing and diagnostic functions directly into the valve housing. This simplifies installation, reduces cabling requirements, and enables direct integration into control systems. ARGO-HYTOS offers both designs, covering the entire spectrum from compact standard valves to powerful precision solutions for large-scale systems.

How does signal-controlled pressure regulation work?

The function of a proportional pressure reducing valve is based on control by an electrical input signal. This signal generates a magnetic force that acts directly on the valve mechanism. Depending on the strength, the opening cross-section through which the oil flows into the secondary circuit changes.

The valve is open when de-energized. The oil then flows unhindered over the control edge into the consumer circuit. As soon as the target pressure is reached on the consumer side, the control edge closes and interrupts the oil flow. In this way, the desired pressure builds up in the secondary circuit and remains constant, even if higher values prevail in the main circuit.

Feedback systems are used to stabilize and control pressure. When the pressure reducing valve is closed (e.g., because the secondary pressure has been reached), pressure can continue to build up in the valve's control chamber. A feedback system returns this pressure to the tank or to the low-pressure side to prevent overload. By returning the control oil flow, the control pressure is kept constant, resulting in more precise pressure control. This increases accuracy and response speed and is particularly important in sensitive applications.

Especially in dynamic processes such as clutch engagement or fast clamping operations, these features ensure maximum reliability and process quality.

Why are precision and dynamics crucial factors for pressure reducing valves?

In modern hydraulic systems, consistent process quality, energy efficiency, and operational safety are key requirements. Proportional pressure reducing valves contribute to this by precisely adjusting the output pressure to the requirements.

This is particularly important when sensitive actuators have to be operated within a narrow pressure range. Precise control prevents unnecessary wear and tear and increases the service life of the components.

Dynamic behavior is equally crucial. Valves from ARGO-HYTOS are characterized by short response times and low hysteresis. This allows even fast load changes or transient processes, such as when controlling clutches, to be reliably controlled. This ensures stable processes and prevents pressure peaks that would put strain on the systems.

In addition, the valves are designed for integration into modern control concepts. They are compatible with PLCs, industrial controllers, and networked Industry 4.0 environments. Interfaces such as CANopen or analog signal paths enable direct integration into automated systems. Diagnostic functions support predictive maintenance. This makes proportional pressure reducing valves a key technology for the automation and digitalization of hydraulic applications in mechanical engineering, industry, and mobile hydraulics.

Overview of the advantages of proportional pressure reducing valves

• Stepless, dynamic pressure control via electrical signal
• Protection of sensitive consumers through constant pressure reduction
• High accuracy thanks to feedback and closed control loops
• Fast response and low hysteresis for variable loads
• Available in direct and pilot-operated designs
• Variants with integrated electronics for easy integration
• Compatible with PLC and Industry 4.0 environments

What is the practical significance of proportional pressure reducing valves?

Proportional pressure reducing valves ensure that subcircuits are supplied with precisely defined pressures. This is independent of the supply pressure in the main circuit. This allows complex systems with multiple parallel functions to be implemented without the need for additional pumps or power units. Typical areas of application are:

• Construction machinery
• Agricultural equipment
• Test benches
• Industrial manufacturing equipment

In construction machinery, for example, they precisely control the steering or auxiliary hydraulics. In agricultural engineering, they protect attachments from overload. On test benches, they enable defined pressure curves for test series. In industry, they ensure process quality in injection molding machines, presses, or machine tools.

Thanks to their precision, dynamics, and flexibility, they help to save energy, reduce wear, and increase machine availability. With solutions such as PP2P3-W3 and SP4P2-B3, ARGO-HYTOS offers efficient solutions that meet practical requirements in all areas.

ARGO-HYTOS: Your partner for precise pressure control

Proportional pressure reducing valves combine protection, precision, and efficiency in a single component. They regulate pressures in subcircuits, prevent overloads of sensitive components, and increase the stability of the entire system. Thanks to continuous, signal-controlled adjustment, pressures can be controlled dynamically. This is a basic requirement for modern machines in the age of automation.

ARGO-HYTOS offers direct-acting and pilot-operated designs (optionally with integrated electronics), covering all areas of application from mobile equipment to industrial plants. Machine builders and operators benefit from durable, robust, and precise solutions that improve both process reliability and efficiency. Would you like to learn more or discuss a specific project with us? Then get in touch with our experts.