How to Size a Hydraulic Power Unit for a Cylinder Circuit

A power unit must deliver pressure for force and flow for speed while staying within motor, pump, valve, reservoir and thermal limits.

1. Define Force and Pressure

Use cylinder area and machine load to determine working pressure, including linkage and pressure losses.

Flow equals effective area times piston velocity. Extend and retract can require different flow for equal speeds.

Battery lifts may use short bursts; production machines can cycle for hours. Electrical supply and thermal duty should follow the real cycle.

Direction, load holding, controlled lowering, regeneration and proportional motion are circuit functions. Send a schematic or motion sequence.

Tank orientation, suction conditions, return path, fill/filter access and hose clearance affect reliability.

EP-HPU-DC configurable compact hydraulic power unit for battery or vehicle-powered cylinder circuits.

EP-HPU-AC configurable AC hydraulic power unit for stationary industrial cylinder systems.

EP-HPU-SYS custom hydraulic power unit and valve-manifold system configured around the cylinder circuit and duty.

EP-WP welded through-hole cylinder series with model dimensions, pressure, column-load and port data.

Which comes first, cylinder or power unit?

Define the cylinder operating point and machine motion together.

How does bore affect flow?

Larger area needs more flow for the same speed.

Why does duty matter?

Motor and oil temperature depend on time and repetition.

Is relief a speed control?

No; flow/circuit strategy controls speed.

What should I send?

Cylinder data, load, cycle time, electrical supply, valve sequence, duty and package constraints.

Send bore, stroke, mounting, pressure, ports, load and duty details. For replacements, include photos and critical measurements.