What are the main causes of cavitation in the cylinder tube?
The hazard of cavitation corrosion of the cylinder steel pipe is quite large, it will cause the mating surface to become black, and even the support ring and sealing ring will be burnt, which will cau
The hazard of cavitation corrosion of the cylinder steel pipe is quite large, it will cause the mating surface to become black, and even the support ring and sealing ring will be burnt, which will cause internal leakage of the hydraulic cylinder. When cavitation is common with other types of corrosion When used, it will accelerate the corrosion rate of the main parts of the cylinder steel pipe several times or even dozens of times, which will seriously affect the normal use of construction machinery. Therefore, it is very necessary to prevent the cavitation of the hydraulic cylinder barrel.
⑴ Essential analysis of cavitation
Cavitation occurs mainly because a certain amount of air is mixed into the oil between the piston and the guide sleeve during the working process of the hydraulic cylinder. As the pressure gradually increases, the gas in the oil will become air bubbles When the pressure rises to a certain limit value, these bubbles will burst under the action of high pressure, which will quickly act on the surface of the part with high temperature and high pressure, causing the hydraulic cylinder to produce cavitation and causing the parts to fail. Corrosive damage.
⑵Unqualified hydraulic oil quality leads to cavitation
Ensuring the quality of hydraulic oil is an important factor in preventing cavitation. If the oil has poor anti-foaming properties, it is easy to produce foam, which will lead to cavitation. Secondly, the frequency of oil pressure changes is too fast and too high. , It will also directly cause the formation of bubbles and accelerate the bursting speed of bubbles. Tests have proved that the speed of cavitation in the parts with high frequency of pressure changes will increase. For example, the hydraulic cylinder inlet and return ports, etc., due to the frequency of pressure changes Relatively high, the degree of cavitation is relatively higher than other parts. In addition, overheating of the oil will also increase the probability of cavitation.
⑶Improper manufacturing and maintenance lead to cavitation
Because the hydraulic system is not fully exhausted during assembly or maintenance, there is gas in the system, which can cause cavitation under the action of high temperature and high pressure.
⑷The quality of coolant causes cavitation
When the coolant contains corrosive media, such as various acid radical ions, oxidants, etc., it is prone to chemical and electrochemical corrosion. Under their combined action, the speed of cavitation will also be accelerated; if the cooling system is well maintained, it can be Prevent the occurrence of cavitation. For example, if the pressure cover of the radiator of the cooling system is well maintained, the pressure of the radiator's coolant can always be higher than the vapor pressure, thereby preventing the occurrence of cavitation. Another example is the section of the cooling system. Thermostat; a thermostat with good performance can keep the coolant in a suitable temperature range and reduce the energy released when the bubble bursts.