When high operating pressures are required, piston pumps are often used. Piston pumps will typically withstand higher pressures than gear pumps with similar displacements; however, there exists a higher initial cost associated with piston pumps in addition to a lower level of resistance to contamination and increased complexity. This complexity falls to the gear designer and service specialist to understand in order to assure the piston pump is usually working correctly using its additional shifting parts, stricter filtration requirements and closer tolerances. Piston pumps are often used with truck-mounted cranes, but are also discovered within other applications such as snow and ice control where it could be desirable to 
vary system movement without varying engine swiftness.
A cylinder prevent containing pistons that move around in and out is housed within a piston pump. It’s the movement of the pistons that draw essential oil from the supply interface and then drive it through the store. The angle of the swash plate, that your slipper end of the piston rides against, determines the distance of the piston’s stroke. While the swash plate continues to be stationary, the cylinder prevent, encompassing the pistons, rotates with the pump’s input shaft. The pump displacement is certainly then dependant on the total volume of the pump’s cylinders. Fixed and variable displacement designs are both available.