Hydraulic pressure regulators maintain the output pressure of a hydraulic system at a set value to minimize fluctuations in a pressurized line. 

Hydraulic pressure regulators maintain a specific pressure range and are commonly known as unloading valves or unloading relief valves. In hydraulic power systems, these regulators both unload the fluid being pumped and regulate a set operating pressure. All positive displacement fixed-volume pumps for hydraulic circuits require an unloading valve to protect the system from excess pressure. Fixed-volume pumps move a set amount of fluid when they turn, regardless of pressure. If the system is not using that fluid it must be relieved to prevent system overpressure. When a pump is unloading through an open-center circuit or actuators are in motion, fluid movement is not a problem. When actuators or motors stop with a valve still sending fluid to those devices, a relief valve is required. 

In a hydraulic circuit, a hydraulic pressure regulator opens and bypasses fluid when pressure exceeds its setting. The valve then closes again when pressure falls. The valve acts as a pressure relief valve and can bypass fluid anytime without intervention. 

Many hydraulic pump circuits depend on this bypassing capability during the cycle, and some even bypass fluid during idle time. A well-designed circuit rarely bypasses fluid unless there is a malfunction. Limiting bypassed fluids eliminates most overheating problems and saves energy. 

Configurations 

A hydraulic regulator is typically made of steel, coated steel, or stainless steel and comes with a variety of connections. Hydraulic regulators are designed to hold a tight seal even as the pressure in the line rises.

Applications

The devices may be used in land-based applications or may be specially designed to work underwater.

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Barksdale Control Products