A radial piston pump is a hydraulic pump with rotating pistons that spin symmetrically around a central drive shaft. The pistons are pressed in and out of cylinders surrounding the main shaft rotor as the block rotates, effectively creating a pump function.
The mechanical process of the radial piston pump operates conversely from the process of a radial piston motor. Fluid is forced into the cylinders that drive the piston forward in the traditional radial piston motor, whereas in a radial piston pump, the pistons receive fluid and force it out into the system.
A radial piston pump is a useful device in a number of practical applications, including power tools, injection moulding, machinery, wind energy, and most commonly, in the automotive sector. A radial piston pump can be found in the automatic transmission of many vehicle models, as well as in hydraulic suspension control systems popular in upper-class, high-end vehicles.
A number of attributes characterize radial piston pumps, such as high pressure, efficiency, reliability and the potential for high work loads even at low speeds. These pumps are also utilized for their low flow and pressure ripple, low noise level and the absence of axial internal forces at the drive shaft bearing.