Fluid power systems operate via pressurised fluid directed on a piston in a cylinder or into a fluid motor. Fluid cylinders create force which results in linear motion, while fluid motors create torque resulting in rotary motion.
Hydraulic machines are designed to convert mechanical energy into fluid energy as pressurised fluid (usually oil) is passed through a hydraulic cylinder to provide linear motion, or through a hydraulic motor to produce rotary motion/torque.
Hydraulics are often preferred due to the incompressible oil. This allows for large amounts of force to be transferred relatively easily. Hydraulic machines work in conjunction with pumps, valves, tubes and fittings. Hydraulic cylinders and pumps provide force and transfer the flow and direction of liquid in hydraulic machines, while valves control the flow and direction of the liquid. Other key accessories for hydraulic machines include clamps, accumulators and tubes fittings.