Grease degradation alternate test method and storage interval for roller bearings: An empirical research
List of Authors
  • K. K. Nithia , M. Y. Noordin

Keyword
  • Grease, Lubrication, Degradation, Roller bearings

Abstract
  • Pandemic caused parts into prolong storage conditions. Empirical experiment was carried out to determine the viscoelastic behaviour and consistency of unworked grease from inside a wheel roller bearing. The grease samples intervals were 9, 10, 11 and 24 months from stored wheel roller bearings. Fresh grease is also tested as a controlled sample. A rheometer amplitude oscillation test was performed. The grease was tested for contaminants such as oxidation, nitration, soot, sulfation, and water using FTIR. Rheology test exhibited changes in viscoelastic behaviour. Grease consistency changed from grade 2 to grade 1. This confirms that the grease tends to soften and degrade over time. FTIR results revealed that there is no significant contaminant for unworked and packed grease in the wheel. Storage and maintenance interval derived from this study.

Reference
  • 1. Gurt, A.; Khonsari, M.M. Testing Grease Consistency. Lubricants 2021; 9, 14. https://doi.org/10.3390/lubricants9020014

    2. Couronne, I., Blettner, G., and Vergne, P. Rheological Behaviour of Greases: Part I—Effects of Composition and Structure, Tribology Transactions, 2000; 43(4), pp 619-626.

    3. Behzad Zakani & Dana Grecov. Yield Stress Analysis of a Fumed Silica Lubricating Grease, Tribology Transactions, 2018; 61-6, 1131-1140, DOI: 10.1080/10402004.2018.1499987

    4. Lugt, P. M. Grease Lubrication in Rolling Bearings, John Wiley & Sons: West Sussex, UK. 2013.

    5. Cyriac, F., Lugt, P. M., and Bosman, R. On a New Method to Determine the Yield Stress in Lubricating Grease,Tribology Transactions, 2015; 58(6),1021–1030.

    6. Balan, C. and Franco, J. M. Influence of the Geometry on the Transient and Steady Flow of Lubricating Greases, Tribology Transactions, 2001; 44(1), 53–58.

    7. Ito, H., M. Tomaru and T. Suzuki. Physical and Chemical Aspects of Grease Deterioration in Sealed Ball Bearings, Lubrication Engineering, 1988; 44(10), 872–879.

    8. Yuxin Zhoua, Rob Bosmana and Piet M. Lugt. A model for shear degradation of lithium soap grease at ambient temperature. Society of Tribologists and Lubrication Engineers. 2017; 38-47.

    9. Van den Kommer, A. and Ameye, J. Prediction of Remaining Grease Life-A New Approach and Method by Linear Sweep Voltammetry, Proceedings Esslingen Conference, 2001; 891-896.

    10. Delgado AM, Valencia C, Sanchez MC, Franco JM, Gallegos C. Influence of soap concentration and oil viscosity on the rheology and microstructure of lubricating greases. Industrial Engineering Chemical Research, 2006; 45:1902–10

    11. Lugt Piet. A review on grease lubrication in rolling bearing. Tribology Transaction, 2009; 52. 470-480.

    12. Lundberg J, Höglund E. A new method for determining the mechanical stability of lubricating greases. Tribology International, 2000;33(3–4):217–23.

    13. Bauer, W.H., Finkelstein, A.P., and Wiberley, S.E. Flow Properties of Lithium Stearate-Oil Model Greases as a Function of Soap Concentration and Temperature, ASLE Transactions, 1960; 3, 215-224.

    14. Hurley, S. Fundamental Studies of Grease Lubrication in Elastohydrodynamic Contacts, PhD Thesis, University of London, Imperial College of Science, Technology and Medicine, UK. 2000.

    15. Forster, E.O., Kolfenbach, J.J., and Leland, H.L. Fibers, Forces and Flow, NLGI Spokesman, 1956; 20(3), 16-22.

    16. Lugt Piet. A review on grease lubrication in rolling bearing. Tribology Transaction, 2009; 52. 470-480.

    17. Scarlett, N.A. Use of Grease in Rolling Bearings, Proceeding IMechE. 1967; Part 3A, 182, 167-171.

    18. Gurt, A.; Khonsari, M.M. Testing Grease Consistency. Lubricants, 2021; 9, 14. https://doi.org/10.3390/lubricants9020014

    19. Deutsches Institut für Normung. Testing of Lubricants — Determination of Shear Viscosity of Lubricating Greases by Rotational Viscosimeter — Part 1: System of Cone/Plate, 2007

    20. Michael C. Garry, John Bowman, Thermo Fisher Scientific, Madison, FT-IR Analysis of Used Lubricating Oils – General Considerations, WI, USA. 2007 Thermo Fisher Scientific Inc.

    21. Chen, Y., Zou, C., Mastalerz, M., Hu, S., Gasaway, C. and Tao, X. Applications of micro Fourier transform infrared spectroscopy (FTIR) in geological sciences: A review. International Journal of Molecular Science. 2015;16. 30223-30250.

    22. Zzeyani, S., Mikou, M., Naja, J. and Elachhab, A. Spectroscopic analysis of synthesis lubricating oil. Tribology International, 2017; 144. 27-32.