ANALYSIS OF MODEL TESTS OF BALL BEARINGS FOR HIGH-SPEED ROTORS

Oleg Badun, Halyna Horbenko

Abstract


The article discusses the performance of ball bearings in the absence of lubrication and cooling, that is, in dry friction conditions. Six samples of ball bearings in two sizes (6204 and 6205) were selected for testing, which differed in the design of the separator and the material of individual elements. The first sample is made entirely of spring steel and has a steel riveted separator. The second sample differs from the first only by replacing the separator material with polypropylene, the third differs in a massive solid separator made of fluoroplastic-4 and the fourth differs in ceramic balls and a polypropylene separator. The fifth sample is unseparated and entirely ceramic. The sixth sample, unlike the fifth, has a massive separator made of fluoroplastic-4. The goal is to select the separator design and the material of the ball bearing elements to ensure the maximum possible service life in dry friction conditions. Task: to identify the nature of the influence of design features and selected materials on the service life of ball bearings. The method used is hydraulic testing of ball bearings as part of a special installation that provided a wide range of flow rates through the ball bearing, including zero. The following results were obtained. In the absence of cooling and lubrication, that is, in dry friction conditions, the tested ball bearings had a low service life. The steel ball bearing with a riveted separator had the highest service life, but it suffered the greatest destruction. Replacing the metal separator with a non-metallic one reduced service life. The use of ceramics turned out to be appropriate only for the manufacture of balls, since ceramic cages are destroyed very quickly due to severe overheating of the material. Conclusions. The scientific novelty of the results obtained is as follows: it was established that in dry friction mode it is advisable to use separatorless hybrid ball bearings with metal cage and ceramic ball.  


Keywords


ball bearing; separator; ball; cage; hydraulic test; service life; dry friction; operating mode

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DOI: https://doi.org/10.32620/aktt.2026.3.05