Hydrastore power unit

Hydraulic Power Units & Systems, Design & Manufacture

We have the capability to design and manufacture bespoke manifolds. We also hold a vast stock of premium brand hydraulic components, electronic and radio control equipment. This is combined with a wealth of system and application knowledge. Our company prides itself on delivering fit for purpose, cost effective and reliable systems. Our Hydraulic systems section provides an insight into the many applications we support.

What is a hydraulic power unit?

What is a:

  • Hydraulic Power Unit (HPU)
  • Hydraulic power pack.
  • Power pack.

The above are common terms used to describe a collection of components which; together produce flow and have pressure capability. Primary elements of a hydraulic power unit are:

  • Prime mover - source or rotary power, to drive a hydraulic pump, examples include: electric motor, an engine and more recently a hybrid system
  • Hydraulic pump - driven by the prime mover, the pump delivers flow into a hydraulic system for the operation of actuators
  • Reservoir - The source of oil to be used in a hydraulic system, these are mainly steel or plastic construction
  • Valves - A means controlling pressure, flow or direction of oil flow in the HPU system
  • Actuators - Typically these are located away from the HPU and carry out functions where high levels of force are applied.

At Hydrastore we produce hydraulic power units with prime movers ranging from 0.5 kW up to 500 kW. Pressure capability is up to 450 bar and above with flows ranging from single digits into thousands of litres per minute. Our HPU‘s are carefully engineered for high levels of system efficiency. We are proud to say that our HPU‘s are low noise, energy efficient and highly reliable. For these reasons, our customers consistently realise benefits in terms of a low total acquisition cost.

HPU‘s can also contain different valves such as relief valve or a pressure compensating component that prevents damage by limiting system pressure to an acceptable level. Other systems may have control valves that operate each service for single or bi-directional motion of an actuator. Directional control valves operate an actuators direction and speed (flow rate) and can sometimes limit the pressure below that of the maximum permissible by the main pressure control of the power unit.

Controlling hydraulic valves can be as simple as manual hand lever or by an electric / electronic control system. A control system can be mounted within the pack or located at a remote location. It is also possible in safety critical areas to control actuators by radio remote control.

Actuators are devices that convert the hydraulic power from the hydraulic power unit into linear force & motion (cylinders) or rotary force and motion (motors & rotary actuators).

  • Cylinders: These are sometimes referred to as rams which push or pull heavy loads.
  • Hydraulic motors: These are able to rotate continuously providing rotational torque
  • Rotory actuators: provide accurate 0 to a max. 360 degrees of angular positional control and can also deliver enormous rotational torque with excellent load hold holding characteristics

Components of each hydraulic power unit element

Hydraulic power units consist of a:

  • Hydraulic tank
  • Tank filler breather
  • Suction strainer
  • Oil level sight gauge
  • Air Filter breather
  • Desiccant breather
  • Oil Heater
  • Oil Cooler
  • Oil level switch
  • Return line filter
  • Pressure line filter
  • Inspection hatch

Prime mover:

  • Diesel engine.
  • Petrol engine.
  • AC Electric motor.
  • DC electric motor.
  • Hybrid system


  • Fixed delivery pump.
  • Hand pump
  • Variable pump.
  • Gear pump.
  • Vane pump.
  • Piston pump
  • Screw pump
  • Pressure compensated pump
  • Load sensing pump
  • Power limited pump
  • Torque limited pump
  • Electronically proportional pump
  • Open circuit pump
  • Open loop pump
  • Closed circuit pump
  • Closed loop pump.


  • Pressure relief valve.
  • Pressure reducing valve.
  • Proportional pressure relief valve
  • Proportional pressure reducing valve
  • Flow control valve.
  • Priority flow control valve.
  • Priority steering valve.
  • Directional control valve.
  • Manual valve.
  • Monoblock.
  • Proportional control valve
  • Proportional control directional valve
  • PVG valve
  • Servo valve


  • Hydraulic cylinder
  • Hydraulic cylinder welded construction
  • Hydraulic cylinder tie rod
  • Hydraulic cylinder industrial
  • Hydraulic motor
  • Hydraulic gear motor
  • Hydraulic vane motor
  • Hydraulic piston motor
  • Hydraulic axial piston motor
  • Hydraulic radial piston motor
  • Hydraulic rotatory actuators
  • Helical rotatory actuators
  • Vane rotatory actuators

Get in touch to discuss your requirements

01427 874445