Control of the influence of temperature on degradation processes viscosity-temperature properties of engine oils

The effect of thermal degradation products on the viscosity-temperature properties of motor oils thermostatted at temperatures ranging from 140 to 300°C. Methodology of the study was as follows, oil sample constant weight of 90 g was filled in a device for temperature control and maintained at a predetermined temperature for 8 hours under atmospheric pressure to vapor condensation and the tap. Then I sampled for photometry at a thickness of 2 mm layer of the photo-metric, and determining the absorption of light and the sample weight of 85 g to measure the kinematic viscosity in the temperature range from 40 to 130°C. The temperature of incubation was increased to 20°C. From the values of kinematic viscosity measured at 40 and 100°C was determined by the viscosity index (GOST 25371-97, ISO 2909-81). The data obtained were based graphics depending on the temperature of the viscosity index and temperature control of the absorption coefficient of the light flux, which was determined by the effect of thermal degradation products in the viscosity-temperature properties of engine oils. It is found that with increasing temperature of incubation and concentration of degradation products in the oil temperature viscosity keeps decreasing trend, especially measured at 40°C. There is a temperature range where the viscosity index is practically unchanged.