The high oil temperature of the hydraulic system will cause the hydraulic oil to produce cavitation, reduce viscosity, accelerate the aging of the oil and other adverse consequences, so that the lubrication between the moving parts of the system is poor, wear is intensified, resulting in hydraulic components failure or stuck; At the same time, it will accelerate the aging of the seal and lose elasticity, light oil leakage of the system, and serious hydraulic system downtime.
1 Impact on the viscosity of hydraulic oil In the general industry, the working pressure of the hydraulic system is below 20MPA. Under this pressure, the influence of pressure factors on the viscosity of hydraulic oil can be ignored, and the influence of temperature on the viscosity is mainly considered. When the temperature increases, the cohesion of oil molecules decreases, and its viscosity decreases. The effect of hydraulic oil viscosity reduction on the system is to increase the leakage amount. According to the leakage principle of hydraulic oil gap flow, the leakage amount is proportional to the reciprocal of hydraulic oil viscosity, and the higher the temperature, the double the leakage amount.
