A hydrostatic transmission pump, commonly called a hydraulic pump, is a positive displacement machine and its mission is to transform mechanical energy into hydraulic, based on the Pascal Principle. This Principle is based on the fact that, when exerting a pressure or push on a fluid like oil (which is considered incompressible), it is transmitted equally in all directions.

Taking advantage of this principle, hydraulic actuators, depending on the pressure and displacement surface (eg surface of a piston), will transmit the force necessary to move the application.

Turning the pump drive shaft causes the internal components responsible for the suction and delivery of the oil to be moved, by varying the volume at each turn, called displacement, with a minimum loss and regardless of the pressure of the system.

Put more simply, the pump delivers an oil flow to the system and through a distributor with pressure limiting, the direction, the effort and the speed with which the actuator of the application is moved, which is usually a cylinder (tipper, crane) or a hydraulic motor (winch, winch, wheel, head or other).

They are usually found in mobile applications such as industrial vehicles, civil works or maintenance, as well as industrial applications such as elevators, presses, machine tools and process machinery.

The assembly and actuation of the pump is direct through a power take-off coupled to the vehicle’s gearbox, although an indirect hydrostatic transmission can also be mounted, or by coupling and electric motor (AC / DC) or combustion.

The most frequent types of pumps are manufactured Bezares, s.a. (Spain), such as piston pumps, pallets and gears, being one of the few factories in the world that produces the 3 types and also manufactures power sockets and distributors. 

Finally, recall the Pascal Principle of Pressure:

And if we know the working pressure and the useful surface of the actuator: