Collection:Hydraulic Gear Pumps

Hydraulic gear pumps convert the rotation of an electric motor or engine into hydraulic flow. In an external gear pump, two meshing gears carry oil from the suction side to the pressure side between the gear teeth and the housing. The design is simple, robust and compact, which makes gear pumps the standard choice for power units in industrial and mobile hydraulics.

Gear pumps have a fixed displacement: every revolution delivers the same volume. The flow therefore follows the drive speed, and it cannot be varied at constant speed without a separate flow control or a variable displacement pump. Choose the displacement so that displacement times drive speed gives the required flow, and check the maximum pressure, which often drops as displacement increases.

The mounting interface decides what fits. Match the flange standard, such as Bosch or Plessey in its size, and the shaft type to the motor or bell housing. Also check the port connections: the bolt pattern of the suction and pressure flanges differs between standards, for example German and Italian hole patterns, and the flange name alone does not tell you the port pattern. Finally, order the pump for the direction of rotation of the drive.