The effects of three different additives formulations namely Lubrizol 21001, HiTEC 8722B and HiTEC 340 on the efficiency of VII namely OCP of three base lubricating oils namely 40 stock and 60 stock and 150 stock at four temperatures 40, 60, 80 and 100oC were investigated. The efficiency of OCP is decreased when blended with 4 and 8 wt% of Lubrizol 21001 for all the three base oil types. But it is increased when adding 4 wt% and 8 wt% of H-8722B in 40 stock. While for 60 stock and 150 stock the OCP efficiency decreased by adding 4 and 8 wt% of H-8722B. In the other hand, it is decreased with a high percentage by adding 4 and 8 wt% of H-340 for 60 stock and 150 stock and for 40 stock it is increased by adding 4 wt% of H-340 and decreased with insignificant percentage when adding 8 wt%. Finally, a number of VI correlations have been obtained depending on the results predicted in this study. These correlations represent the functional relationships between the VI and the concentration of OCP for three types of base lubricating oil and for each type of additives.
Keywords: Lubricating oil, Kinematic Viscosity, Viscosity
The study of human factors and the extent of their impact on the construction of land transport roads is of great importance because they are variable factors, which are on the contrary natural factors, and the impact of human factors on road construction operations is evident through the study of population distribution and size, and economic activities (agricultural, industrial, tourism). And its direct mutual relationship with the construction and extension of land transport routes and the development of each of them, and then directing them to serve urban and rural human settlements, which leads to their development and improvement of their economic, living and social conditions on the one hand, and contributes to the emergence
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