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If cavitation occurs in the hydraulic system, the bubbles in the liquid move with the flow toward areas of higher pressure; under this higher pressure, the bubbles burst rapidly, resulting in localized hydraulic shocks that cause noise and vibration. On the other hand, since these bubbles disrupt the continuity of the fluid flow, they reduce the capacity of the oil pipes to transport fluid, leading to fluctuations in flow rate and pressure. This puts stress on the hydraulic components and affects their service life. At the same time, the oxygen in the bubbles can also corrode the surface of metal components; we call this type of corrosion caused by cavitation erosion. In hydraulic transmission systems, cavitation can occur in oil pumps, pipelines, and other areas with throttling devices; it is most common in oil pump systems. To reduce cavitation, the pressure at all points within the hydraulic system should be higher than the air separation pressure of the hydraulic oil. For example, it is important to ensure that the suction height of the oil pump is not too great, that the diameter of the suction pipe is not too small (as a too small diameter will result in high flow rates and thus a very low pressure drop), that the rotation speed of the oil pump is not too high, and that the pipelines are properly sealed, with the outlet of the oil pipe being below the oil surface. In short, sharp changes in flow rate and the intrusion of external air should be avoided. Cavitation is one of the causes of various faults in hydraulic systems, and special attention must be paid to it in high-speed, high-pressure hydraulic equipment.