Evaluation of the influence of motor oil ultrasonic processing on the wear of friction pairs during long-term wearing tests

Introduction. The influence of ultrasound parameters on the properties of processed lubricating oils and wear characteristics of friction pairs is a relevant problem in agricultural engineering. The paper presents a simple method for influencing on the lubricating oil by ultrasonic vibrations of the optimum frequency and power that results in reducing the wear of the interfaces of mechanisms and machines. The authors study the change in the physical characteristics of the oil during its ultrasound treatment and the assessment of their effect on the wear of a friction pair during long-term tests. Materials and Methods. We used a generator with variable signal parameters, a lever scale, a burette and an alcohol thermometer to assess the change in coefficient of surface tension of engine oil during sonication. Long-term tribotechnical tests were carried out on 2070 CMT-1M friction machine according to the “roller - pad” scheme. The mass of these samples after long-term tests was weighed by Sartorius company analytical scales with a measurement accuracy of 0.00001 g. A profilograph-profilometer of Taylor Hobson Company was also used. Results. As a result of the research, the optimum frequency and power of ultrasound were revealed for lubricating oil processing. The decrease in the surface tension coefficient of oil was more than 5 %. With prolonged wear tests, the wear factor was reduced by 28 %. Conclusions. The effect of increasing the wear resistance of friction pairs when exposed to ultrasound oil is associated with a decrease in its surface tension coefficient, which allows the oil to be distributed with minimal effort over the surfaces with forming a film of sufficient thickness, which increases the bearing capacity of rubbing surfaces.