A hydraulic gear pump functions as a vital component within hydraulic systems by converting mechanical energy into hydraulic energy by moving hydraulic fluid through the pump assembly, often in conjunction with an engine or electric motor. Gear pumps are used in a wide range of hydraulic systems; in fact, they are easily among the most common types of pumps seen in this type of equipment. Hydraulic gear pumps are of a fixed displacement design and operate by means of a prime mover such as an engine or motor to pump the fluid.

Although there are several uses for gear pumps and significant variations in gear pump components, their basic design and theory of operation is as follows. Every pump includes two (sometimes more) rotating gears whose teeth interlock. The rotation of the drive shaft turns the drive gear, which, due to the intermeshing design, also puts the other gear into motion. Hydraulic gear pumps do not create a trong suction, so they operate best with a flooded inlet. A gear pump can be run in a clockwise, anti-clockwise or bi-rotational direction but is most efficient when driven in the single direction it was built and tested in.

These pumps are constructed from diverse materials such as cast iron, aluminium, steel, and even plastics or composites, each chosen based on the durability, fluid compatibility, and operating pressure requirements of the system. Hydraulic pump applications span a variety of industries, including the agriculture, marine, mining, and construction sectors, where their ability to handle heavy-duty tasks in service vehicles and other types of heavy equipment is extremely useful.

Whether operating within the tightly controlled environment of industrial machinery or enduring the harsh conditions of outdoor agricultural equipment, hydraulic gear pumps are essential. Their versatility and reliability enable a wide range of applications, such as lifting and moving materials in construction sites, driving the hydraulic systems of commercial ships, and providing the muscle behind mechanised operations in farming—all with the might of fluid power.