For truck-mounted hydraulic systems, the most typical design in use is the equipment pump. This design is certainly characterized as having fewer shifting parts, being easy to support, more tolerant of contamination than other designs and relatively inexpensive. Gear pumps are set displacement, also known as positive displacement, pumps. This implies the same Gear Pump china volume of flow is produced with each rotation of the pump’s shaft. Gear pumps are rated in conditions of the pump’s maximum pressure rating, cubic inch displacement and maximum input speed limitation.
Generally, gear pumps are used in open center hydraulic systems. Gear pumps trap oil in the areas between the 
the teeth of the pump’s two gears and your body of the pump, transport it around the circumference of the apparatus cavity and then power it through the outlet interface as the gears mesh. Behind the brass alloy thrust plates, or wear plates, a little amount of pressurized oil pushes the plates tightly against the apparatus ends to improve pump efficiency.