Fluid power

Fluid power is the use of fluids under pressure to generate, control, and transmit power. Fluid power is subdivided into hydraulics using a liquid such as mineral oil or water, and pneumatics using a gas such as air or other gases. Compressed-air and water-pressure systems were once used to transmit power from a central source to industrial users over extended geographic areas; fluid power systems today are usually within a single building or mobile machine.

A fluid power system has a pump driven by a prime mover (such as an electric motor or internal combustion engine) that converts mechanical energy into fluid energy, eventually using a set of control valves and dedicated circuit architecture. This fluid flow is used to actuate a device such as:

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