What is the role of the hydrostatic pressure balance in Rexroth piston pumps?

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In the operation of Rexroth piston pumps, it is common for there to be high pressure on one side and low pressure on the other. As a result, an unbalanced hydraulic force is generated. This unbalanced hydraulic force acts on components such as the rotor and bearings, accelerating their wear; it disrupts the proper operation of the Rexroth plunger pump; and it shortens its service life. Therefore, in such a situation, the Rexroth piston pump must use hydrostatic pressure to maintain balance. Hydraulic pumps with different structures have various balancing methods; for example, gear pumps and vane pumps in Rexroth piston pumps employ different balancing approaches. The Wigus vane pump uses a structure with balanced rotor radial forces achieved through paired suction and discharge ports, whereas the Niigata gear pump employs a radial force balancing structure that directs high-pressure oil to the low-pressure area. Since Rexroth piston pumps are unable to balance the pressures generated by high-pressure and low-pressure oils, thrust bearings are used to address this issue; this is also why Rexroth piston pumps generally have a larger size compared to Wegovia vane pumps and Nippon Seiki gear pumps. Regardless of the type of hydraulic pump, managing the balance of hydrostatic pressure is a rather important issue. However, hydraulic system technology has now become increasingly mature, and the basic hydraulic pumps available on the market can handle this aspect perfectly. Therefore, when purchasing hydraulic pumps, one can confidently choose the type they desire.