Comparative Study of the Impact of Corundum Particle Contaminants Size on Wear and Fatigue Life of Grease Lubricated Ball Bearings
- 1 School of Mechanical Engineering, National Technical University of Athens, Athens, Greece
- 2 School of Mechanical Engineering, National Technical University of Athens, Athens, Greece
- 3 School of Mechanical Engineering, National Technical University of Athens, Athens, Greece
- 4 School of Mechanical Engineering, National Technical University of Athens, Athens, Greece
Abstract
Ball bearings’ rating life is reduced with the presence of hard particle contaminants in the lubricant. This life reduction is taken into account when calculating the modified rating life by using the contamination factor. The contamination factor is based on a general characterization of the lubrication conditions but the impact of contaminant’s variables such as size, hardness and concentration level is not determined in detail. In this work, greases contaminated with hard corundum (alumina, Al 2 O 3 ) particles of different sizes are tested aiming at finding a pattern in the relationship between particle sizes’ and wear’s progress. A laboratory rig is utilized for these tests and vibration analysis tools regarding bearings ’ condition and estimated residual life are being assessed. After the tests, optical inspections using a stereoscope verify the vibration analyses results. The experimental results show that wear is progressing faster when smaller particles are used. The crystalline structure of the corundum and the different degree of brittleness of the contaminants seem to be the reasons for this behavior, whereas severe abrasion and deformation of the raceways have been detected.
- A. Palmgren and G. Lundberg, “Dynamic Capacity of Rolling Bearings,” Acta Polytechnica, Vol. 1, No. 3, 1947, p. 7.
- T. A. Harris, M.N. Kotzalas, “Advanced Concepts of Bearing Technology,” 5th Edition, CRC Press, Boca Raton, 2007.
- E. V. Zaretsky, J. V. Poplawski and C. R. Miller, “Rolling Bearing Life Prediction—Past, Present and Future, NASA TM-2000-210529, NASA Glenn Research Center, 2000, p. 13.
- International Organization for Standardization, ISO 281: 2007, Rolling Bearings—Dynamic Load Ratings and Rating Life, 2007.
- M. Godet, “The Third Body Approach: A Mechanical View of Wear,” Wear, Vol. 100, No. 1-3, 1984, pp. 437-452. http://dx.doi.org/10.1016/0043-1648(84)90025-5
- G. K. Nikas, “A State-of-the-Art Review on the Effects of Particulate Contamination and Related Topics in Machine-Element Contacts,” Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, Vol. 224, No. 5, 2010, pp.453-479. http://dx.doi.org/10.1243/13506501JET752
- M. M. Maru, R. S. Castillo and L. R. Padovese, “Study of Solid Contamination in Ball Bearings through Vibration and Wear Analyses,” Tribology International, Vol. 40 No. 3, 2007, pp. 433-440. http://dx.doi.org/10.1016/j.triboint.2006.04.007
- G. K. Nikas, R. S. Sayles and E. Ioannides, “Effects of Debris Particles in Sliding/Rolling Elastohydro Dynamic Contacts,” Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, Vol. 212, No. 5, 1998, pp. 333-342. http://dx.doi.org/10.1243/1350650981542146
- R. S. Dwyer-Joyce, “Predicting the Abrasive Wear of Ball Bearings by Lubricant Debris,” Wear, Vol. 233-235 1999, pp. 692-701. http://dx.doi.org/10.1016/S0043-1648(99)00184-2
- R. S. Dwyer-Joyce, “The Life Cycle of a Debris Particle,” Tribology and Interface Engineering Series, Vol. 48 2005, pp. 681-690. http://dx.doi.org/10.1016/S0167-8922(05)80070-7
- R. S. Dwyer-Joyce, J. C. Hamer, R. S. Sayles and E. Ioannides, “Surface Damage Effects Caused by Debris in Rolling Bearing Lubricants, with an Emphasis on Friable Materials,” Proceedings of the Institution of Mechanical Engineers Symposium on Rolling element bearings, 1990, pp. 1-8.
- R. S. Sayles, “Debris and Roughness in Machine Element Contacts: Some Current and Future Engineering Implications,” Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, Vol. 209, No. 3, 1995, pp. 149-172. http://dx.doi.org/10.1243/PIME_PROC_1995_209_421_02