Hydraulic Pumps in Focus Hydrostatic drive systems are used to operate a number of different machinery systems. Hydrostatic drive systems use hydraulic fluid to operate and are also known as hydraulic power transmission. A typical system will include piping, valves and filters to help guide and maintain the fluid, in addition to a mechanical motor to drive it. Finally, there will also be a hydraulic pump which will handle the fluid. The main purpose of the pump is to ensure that the fluid is under the correct pressure to perform efficiently. It’s an essential component of the system. Hydraulic pumps are available in two different types. One is a hydrostatic and the other is hydrodynamic. The term hydrostatic refers to creating enough pressure for the hydraulic fluid to operate under. Hydrodynamic is more about moving the fluid through the hydraulic system. Working in a similar fashion to positive displacement pumps, hydraulic pumps can be purchased at all different budgets. The more expensive ones will usually deliver more flow and pressure than the cheaper ones. Although most hydraulic pumps may be categorised as fixed displacement, some are classified as adjustable displacement. A screw pump has two screws and is used to deliver low pressure but high flows. This makes it ideal for use on ships where it may be used for the steering gear and to help drive systems in addition to controlling ball valves. Another type of pump is the Gerotor. Deliver far more efficiency through delivering a medium pressure. They are economical and are suitable for use in simple hydraulic systems. However, the efficiency of the Gerotor is not so good at higher pressures. This is where a vane pump would be more suited. The axial piston pump is known for delivering the best efficiency of pumps. They can handle up to 350 bars of pressure. Radial pumps will handle high pressure and small flows.