The function of the cylinder transforms the mechanical energy output by the engine into hydraulic energy, and distributes the main control valve to the executive components to realize the excavator's action. When repairing the mechanical cylinder, we often see some honeycomb holes on the inner wall of the hydraulic cylinder, piston or piston rod, which are caused by cavitation.
Cavitation is a phenomenon of cavernous corrosion on metal surface contacted by fluid under the condition of high-speed flow and pressure change. The following is the method to prevent the cylinder cavitation of excavator introduced by Xiaobian.
The harmfulness of cavitation erosion in mechanical cylinder is quite great. It will lead to blackening of mating surface, even burning of supporting rings and sealing rings, which will cause internal leakage of excavating cylinder. When cavitation and other types of corrosion work together, it will accelerate the corrosion rate of the main parts of the cylinder several times or even tens of times, thus seriously affecting the normal use of machinery. Therefore, it is necessary to prevent the cavitation erosion of the cylinder.
The preventive measures we should take for cavitation erosion are: strict selection of hydraulic oil, strict selection of hydraulic oil in accordance with oil standards. Choosing good quality hydraulic oil can effectively prevent bubbles from occurring in the working process of the hydraulic system; keep the normal clearance between the joints of various hydraulic components; when manufacturing or repairing the main parts of the hydraulic cylinder, it should be assembled according to the lower tolerance limit of assembly size.
This can well reduce the occurrence of cavitation; to prevent oil temperature from being too high, to reduce hydraulic impact, to reasonably design heat dissipation system and to prevent oil temperature from being too high are the keys to maintain the normal temperature of hydraulic oil. If there are abnormalities, we should find out the reasons and eliminate them in time.
At the same time, the cooling system should be maintained in time so that the temperature of the cooling system can be kept within an appropriate range to reduce the energy released when the bubbles burst. When necessary, the intake pipe of the cylinder can be disassembled to make the hydraulic oil overflow, so as to achieve the effect of exhaust of a single cylinder.