Assessment of the Tribological Properties of Lubricating Fluids in the Bearings of a Transverse Screw Shaft

This article presents a comparison of the rheological properties of lubricating fluids and an investigation of their effect on energy consumption during the operation of the transverse bearings of a ship’s propeller shaft. Two testing procedures were carried out. In the first part, an analysis of histograms generated from measurements on an Anton Paar GmbH DV-1P rotational viscometer with coaxial cylinders was performed, enabling the investigation of thixotropic behavior. In the second part, tests were conducted according to standards and an energy parameter related to the specific work of wear of the test material was determined. The test material consisted of steel bearing balls immersed in the lubricant under study and forming part of the friction assembly on a T-02 four-ball tester produced by the Institute of Technology of Operation in Radom. The proposed parameter characterizes the amount of frictional work required to remove material from the surface of the steel balls under a given load, expressed in Nm. The determined specific wear work serves as an integral energy parameter whose value can be used to assess the tribological properties of lubricants.