3RD INTERNATIONAL CONGRESS ON TECHNOLOGY - ENGINEERING & SCIENCE - Kuala Lumpur - Malaysia (2017-02-09)

Optimization Of Bio-mineral Cutting Lubricants

Lubricants in metal machining operations play an essential role in controlling the quality of the final product. Different approaches have been researched to improve the performance of metalworking fluids. The use of vegetable oils such as peanut oil and fatty acid methyl esters such as palm oil methyl ester (POME) have been studied and have been shown to improve the machining operation parameters. These two types of lubricants have environmental and lubricating advantages over conventional mineral oil based lubricants. Characterization of the properties of metalworking fluids helps to identify the composition of the base fluid, predict the coefficient of friction and film thickness, and assess the ability of heat removal of a fluid of interest. In this study, density, dynamic viscosity, thermal conductivity and evaporation losses were measured and analyzed for naphthenic base oil, groundnut oil, blends ratios of 3:1, 1:1 and 1:3 by weight of naphthenic-groundnut. In addition, another set of samples were prepared by adding POME to the aforementioned. POME was added at volume fractions of 0.03, 0.05 and 0.07. The dynamic viscosity was measured at temperatures of 24 ℃, 40 ℃ and 100 ℃. The density was measured at temperatures of 24 ℃, 40 ℃ and 100 ℃. The thermal conductivity was measured at temperatures of 25 ℃, 40 ℃, 55 ℃ and 70 ℃. The evaporation loss was evaluated using the TGA Noack test. The kinematic viscosity was calculated by using the density and dynamic viscosity data. The viscosity index, thermal conductivity and evaporations losses results were modelled using quadratic functions under experimental setup of full factorial design. The models are proposed to be used for variety of optimization problems of the peanut oil and POME contents for this class of lubricants. The results show that as the content of the peanut oil increases, the viscosity index increases. This shows that the peanut oil contributes to higher stability of the viscosity as the temperature is varied. On the other hand, POME was found to decrease the viscosity index as its content is increased. This shows that POME can be a valuable additive for applications in which lower viscosity indices are desired. Analysis of the thermal conductivity shows that peanut oil has a higher thermal conductivity when it is compared to the naphthenic based mineral oil. This shows that groundnut oil is capable of removing the heat generated during machining more efficiently than the naphthenic base oil. In contrast, POME content and temperature did not show strong influence on thermal conductivity. In addition, it was found that by increasing the content of the peanut oil, the evaporation losses are reduced.
Mohamed Osama, Rashmi Walvekar, TCSM Gupta, Wong Yin, Mohammad Khalid