1. The factors affecting cavitation are that when the surface of hydraulic cylinder parts moves relative to hydraulic oil, the gas dissolved in the hydraulic oil is prone to precipitate and form bubbles. After these bubbles flow to the high-pressure zone, they rupture, and the high-temperature and high-pressure micro jet and impact force generated in an instant repeatedly act on the surface of hydraulic cylinder parts, causing cavitation on the surface of the parts. The conditions for the occurrence of hydraulic cylinder cavitation are related to the hydraulic system structure, hydraulic cylinder component materials, hydraulic oil quality, manufacturing and maintenance, and other aspects.
(1) If the channels of the hydraulic system's pipelines, control valves, and other components are too narrow and there are too many bends in the hydraulic system structure, it will increase the temperature of the hydraulic oil, increase the impact force, and easily generate bubbles in the hydraulic oil, thereby causing cavitation of the hydraulic cylinder.
(2) If the material used for manufacturing hydraulic cylinder parts has good strength, toughness, and corrosion resistance, then its resistance to cavitation is good; Otherwise, cavitation is prone to occur. In addition, the uniformity of material organization also has a significant impact on cavitation. The more uneven the material organization, the easier it is to produce cavitation in areas with weak strength and low corrosion resistance.
(3) The quality of hydraulic oil is an important factor in determining whether cavitation occurs in hydraulic cylinders. The hydraulic oil will inevitably have impact with valves, pipelines, etc. during operation. If the hydraulic oil has poor foam resistance, it is easy to produce foam, which will lead to cavitation in hydraulic cylinders and other parts. If the frequency of hydraulic oil pressure changes too fast or too high, it will also promote the formation of bubbles and accelerate the rate of bubble rupture. For example, at the inlet and outlet of hydraulic cylinders, due to the relatively high frequency of pressure changes, the degree of cavitation is also relatively higher than other parts.
(4) The impact of the assembly or maintenance quality of hydraulic cylinders on their cavitation cannot be underestimated. If the hydraulic system is not fully vented during assembly or maintenance, it will result in the presence of gas in the system, and under the action of high temperature and pressure, the hydraulic cylinder will produce cavitation.
2. Although there are various factors that affect the occurrence of cavitation in hydraulic cylinders, measures to prevent cavitation can be avoided as long as necessary measures are taken for active prevention. The measures are as follows:
(1) Choosing qualified hydraulic oil and selecting hydraulic oil with good quality and appropriate brand can effectively prevent the generation of bubbles in the hydraulic oil during operation. The selection of hydraulic oil should comply with relevant technical requirements, refer to the local temperature, and fill according to the oil dipstick standard.
In addition, it is necessary to keep the hydraulic system clean. The oil quality, oil level and oil color of the hydraulic oil should be checked frequently. If foam or milky white is found in the hydraulic oil, it means that air has been mixed in the hydraulic oil. The air source should be carefully checked and the oil should be replaced. If high water-based hydraulic oil is used, a high mounted hydraulic oil tank should be configured to increase the pressure at the inlet of the hydraulic pump and effectively prevent cavitation of the hydraulic cylinder.
(2) The selection of appropriate hydraulic oil additives The selection of appropriate hydraulic oil additives can effectively inhibit the turbidity or hydration of hydraulic oil, prevent the generation of foam, stabilize the quality of hydraulic oil, and maintain the normal performance of hydraulic oil for a long time.
(3) To prevent excessive oil temperature and reduce hydraulic impact, a reasonable configuration of hydraulic oil heat dissipation device can prevent excessive hydraulic oil temperature. If at work