Electrical unloading hydraulic pressure relief

We offer many ready-made circuits and manifold solutions for pump unloading, meaning that in a system with a fixed-displacement pump, the flow is redirected to the tank.

By doing this, the system pressure is reduced, thereby lowering energy consumption and heat generation.

How pump unloading works

The solutions here are electrically controlled, using a main pressure relief valve with a drain line.

When closed, the valve operates at its set pressure. When the drain line is opened with an electrical valve, the relief valve opens and the system becomes almost pressureless.

Mounting and material for pump unloading

We offer ready-made manifolds for both sandwich and line-mounted solutions. All manifolds are available in aluminum (3000 psi / 210 bar) or steel (5000 psi / 350 bar) and can be supplied with surface treatment.

Pressure relief and pump unloading in one valve

SUN Hydraulics has four electrically controlled pressure relief valves that combine this function in a single valve.

Pressure relief in the neutral position and free flow in the actuated position can be found under the respective section.

Pressure relief in the neutral position and closed in the actuated position can be found under the respective section.

Closed in the neutral position and pressure relief in the actuated position can be found under the respective section.

Free flow in the neutral position and pressure relief in the actuated position can be found under the respective section.