Вплив напрацювання та електричної обробки мастильного матеріалу на зносостійкість підшипників ковзання

Abstract

UA: У статті наведені матеріали експериментальних випробувань підшипників ковзання (дизельного двигуна Д-240) на зносостійкість і ресурс на машині тертя СМЦ-2. Випробування проведені для моторної оливи з різним напрацюванням у двигуні, від початкового стану свіжої оливи до повного напрацювання, що відповідає періодичності регламентної заміни. Також у випробуваннях частина зразків оливи підлягала попередній обробці зовнішнім електричним полем для інтенсифікації поверхневої активності присадок, що призводить до відповідного позитивного впливу на мастильну здатність оливи та зносостійкість елементів підшипників ковзання.

EN: The article presents the results of preliminary studies aimed at establishing the main factors affecting the service life of sliding bearings. The researchers pay special attention to the dominant types of lubrication, the thickness of the lubricating film, the load-bearing capacity of the film, shear resistance during friction, as well as the aging of the oil and the loss of its properties over time. Taking into account the previous achievements, as well as the works of the authors in the direction of increasing the wear resistance and resource of sliding bearings, it is proposed to test the sliding bearings of the D-240 diesel engine on the SMC-2 friction machine. The tests were performed according to the "pad - roller" scheme. In this diagram, the roller simulates the neck of the crankshaft, it is made of HF cast iron. The pad presses against the roller a fragment of the liner, which was made from a real engine liner and is a bimetallic element with a steel base and an antifriction coating of AO-20-1 alloy. In the tests, the sliding friction of the liner fragment on the roller was modeled, and the load modes of the friction pair were set in such a way that mixed lubrication of the bearing or transitional lubrication from limit to hydrodynamic lubrication is achieved. The purpose of the tests was to establish the regularities of the impact of engine oil aging and its electrical processing on the wear resistance and service life of the bearing liners. For this, oil samples were taken from the engine lubrication system. Oil samples with 0, 150, 300 engine hours were tested. The complete experiment consisted of two series of trials. The first series of tests concerned the establishment of the effect of working on the wear resistance when lubricating the bearing with traditional oil taken from the engine. The second similar series of tests included the additional introduction of electrical treatment of the oil samples before it was fed to the bearing model. The values of weight wear of liner fragments were obtained experimentally. The wear resistance and service life of the liners were calculated according to the corresponding dependencies, which are also given in the article. As a result of measurements and calculations, the regularities of the effect of working on the conditional life of the liners were obtained, taking into account the effect of the electrical treatment of the oil.