Features of the operation of engine oils in a combined lubrication system “engine-gearbox”

The paper presents the results of studies on the possibility of recycling part of the heat dissipated by the engine lubrication system into the environment. To increase the efficiency of using waste heat, a contact method of heat exchange is proposed. Studies showed that this method, despite the efficiency of heat and mass transfer processes, the simplicity of devices for its implementation can not always be applicable. With the contact method, there is a direct mixing of two coolants: hot and cold, as a result of which the circulation rate is reduced by more than three times. This contributes to a decrease in the severity of the oil operating conditions in the “engine-gearbox” system. The hot coolant in this case is the engine oil of the running engine, and the cold one is the same oil located in the tractor gearbox. Physicochemical analysis of oil samples taken during operational tests of tractors showed that when extending the service life of the oil in the integrated lubrication system, the main indicators do not go beyond the limit states. It should be noted a slight excess of the content of mechanical impurities relative to their amount in the gearbox of a serial tractor, which is much less than the limiting value of 3%.

engine, gearbox, combined lubrication system, viscosity, ash content, base number, mechanical impurities