High and Low Temperature Resistance
Because of the long-term continuous work, if it is outdoor in summer, the hydraulic oil temperature of the machine may exceed 100 °C, which requires the seal to withstand high temperatures. If it is outdoor in winter, the temperature may be around -40 °C when it is turned on, and the seal is required to withstand low temperatures. Therefore, the sealing system is required to have a wide temperature range.
Stain Resistance
The machine itself travels, and the hydraulic tank is generally relatively small due to volume and weight limitations.Because of the size and weight limitations of the system, it is impossible to install the ideal filtration and cooling system. Due to high temperature, high pressure, and high speed, the hydraulic oil is easily deteriorated, which is the aspect of endogenousstains.There are many stains in the hydraulic oil, but there is no thorough filtration. This is the endogenous stain.The working environment can be very dusty, and it is inevitable that dusts will enter the hydraulic system in multiple ways, causing oil pollution, which is external stains.Therefore, the sealing system is required to be resistant to stains.
Good Sealing Performance
Because the system works outdoors, there is no leaking oil recovery system, and the working medium leaks directly to pollute the environment, so the external leakage requirements are strict. At the same time, for hydraulic oil heating control, pressure holding or maintaining position requirements, so the internal leakage requirements are also very strict.
High PressureResistance
The working pressure of the hydraulic system is high, usually above 20MPa, and some reach about 40Mpa, which is higher than the pressure of the hydraulic system of general industrial application, so the sealing pressure requirement is high.
The Wear Resistance
Because of the high pressure and high temperature of the system pressure, the wear is particularly serious, so the seal is required to have good wear resistance.
Low Friction Coefficient
For excavators, pump trucks and other construction machinery, the hydraulic system has high pressure, the cylinder moves fast, and the seal wear is particularly serious. Therefore, the friction coefficient of the seal must be low, so that the seal can have good wear resistance and a suitable life.