The development of polyurea greases based on paraffin-naphthenic lubricating oil VHVI-4

Department of Chemistry and Technology of Lubricants and Chemotology, Gubkin Russian State University of Oil and Gas (National Research University), Moscow, Russia

Abstract

The purpose of this work was to improve the tribological characteristics and low-temperature properties of polyurea greases, as well as to expand the operating temperatures of their use. In this work, as the dispersion medium were used base oils of groups I (I-20) and III (VHVI-4). Diurea was used as a thickener. The obtained samples of the lubricating greases were analyzed: penetration (GOST 32331-2013), drop-point temperature (GOST 32394-2013), colloidal stability (GOST 7142-74), tribological characteristics (GOST 9490-75), and effective viscosity at -50ºС (GOST 26581-85). Based on the analysis of the obtained data, it was concluded that the best properties have lubricants prepared on the group IIIbase oils. To improve the low-temperature properties, it was proposed to add a 50% ester (DOTF) to the dispersion medium of greases which have better performance.As a result of work done, we concluded that the polyurea greases improved their tribological characteristics and low-temperature properties after adding ether to VHVI-4 (1:1) as a dispersion medium.