MULTI-CRITERIA CHOICE OF BASE OILS IN THE PRODUCTION OF LUBRICANTS BASED ON FUZZY TOPSIS

The friction units in any mechanism play an important role for their effective work as a whole. Modern mechanisms are not only high-precision, but also multi-component systems in which the selection of lubricant is an important task for developers and manufacturers. Developers need to take into account the properties of the friction unit materials and its functionality, loads, and manufacturers to get a final product not only reliable, but also cost-effective, meeting consumer demands. Since lubricants have different composition and functional purpose, a system approach should be used in their selection. The presented paper proposes a methodology of selection of base oil based on their physico-chemical properties (criteria) according to the results of physical experiment and unclear approach. The experimental data were converted into trapezoidal fuzzy numbers, unclear weights of selection criteria were determined, and a Fuzzy TOPSIS procedure was carried out. The proposed approach takes into account the variation of experimental data and measurement uncertainty when grading base oils by their physico-chemical properties.