Thermal Expansion Coefficient of Lubricant Oils.

Omar Mustafa Hussian Al –Kubaisy
Prof.Dr. Dhia Al-Deen Mohamed Kasem

This investigation covers a study of the thermal expansion of basic lubricating oils. The three types of Iraqi base lube oil –Stocks, namely 40 Stock, 60 Stock, 150 Stock and also lubricating oil with additives from Al -Dura refinery.  The investigation also covers the effect of additives on the thermal expansion coefficient of a lubricating oil. The additive that is used polymer poly-isoprene.A study of the effect of the temperature changes and the effect of polyisoperne on the thermal expansion coefficient of lubricating oil has carried out.Measurements were made on measuring the density variation with temperature of the base oil and then blending the basic oil with 4% of polyisoperen and measure the density variation with temperature.Generally polyisoperne increases the thermal expansion coefficient of the base oils with keeping the density decreasing is rather constant during heating.Also this study investigates the thermal expansion coefficient of base oil and additives currently used in Al -Dura refinery and compares
that of the base oil +4%poly isoprene. From the result obtaining in this study a good correlation for calculating the thermal expansion coefficient of three base oil at different temperatures are obtained.