EXPERIMENTAL INVESTIGATION ON RHEOLOGICAL PROPERTIES OF A COMPLEX LITHIUM-CALCIUM GREASE IN FRESH AND USED CONDITION

Alexandru Valentin RADULESCU, Irina RADULESCU

Abstract


The purpose of the paper is to investigate the rheological and tribological properties of a complex lithium - calcium grease, using a cone and plate viscometer and a pin-on-disk tribometer. The experiment was performed on two samples of the same grease, in fresh and used condition (during use in a worm gear). In the course of the experiments, the effect of tackiness and adhesion phenomenon was studied, for both fresh and used grease. Finally, it has been observed a strong dependence between the operating time and technical performances of greases: decreasing the values of the rheological parameters (viscosity and yield stress), increasing of the friction coefficient between tested surfaces and decreasing of the threads length during the adhesion test. The principal result of this research is an alternative method for the evaluation and quantification of the wear degree and lubricants durability.

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References


Gow, G., 2010, Lubricating grease, Chemistry and Technology of Lubricants, 411-432, Springer.

Lugt, P. M., Grease lubrication in rolling bearings, Wiley, New York, 2013

Kawamura, T., Minami, M., Hirata, M., 2001, Grease life prediction for sealed ball bearings, Tribology Transactions, 44 (2), 256-262.

Cann, P. M., Doner, J. P., Webster, M. N., Wikstrom, V., 2001, Grease degradation in rolling element bearings, Tribology Transactions, 44 (3), 399-404.

Aranzabe, A., Estibaliz, A., Arrate, M. et al., 2006, Comparing different analytical techniques to monitor lubricating grease degradation, NLGI Annual Meeting-National Lubricating Grease Institute, 70 (6), 17-30.

Schultheiss, H., Stemplinger, J. P., Thomas, T., Stahl, K., 2015, Influences of failure modes and load-carrying capacity of grease-lubricated gears, International Conference on Gears, Munich, 5-7.

Rezasoltani, A., Khonsari, M., 2016, On monitoring physical and chemical degradation and life estimation models for lubricating greases, Lubricants, 4 (3), 34.

Larsson, M., Duffy, J., 2013, An overview of measurement techniques for determination of yield stress, Annual transactions of the Nordic Rheology Society, 21, 125-318

Couronné, I., Vergne, P., Ponsonnet, L., Truong-Dinh, N., Girodin, D., 1999, Influence of grease composition on its structure and its rheological behaviour, Tribology Series, 38, 425-432

adgurskas, J., Johns, E. I., Radulescu, I., Rdulescu, A.V., Rukuiza, R., Snitka, V., Kreivaitis, R., Kupcinskas, A., Volskis, D., 2023, Tribological study of beeswax-thickened biogrease and its modification with carbon nanoparticles, Tribology International, 184, 108465

Radulescu, I., Radulescu, A.V., Vasiliu, F., 2018, Experimental researches of the grease durability via microscopic investigation”, IOP Conf. Series: Materials Science and Engineering, 444, 022009.

Achanta, S., Jungk, M., Drees, D., 2011, Characterisation of cohesion, adhesion, and tackiness of lubricating greases using approach–retraction experiments, Tribology International, 44, 1127-1133.

“BROOKFIELD CAP 2000+ Viscometer.” 2018. Operating Instructions Manual No. M02-313-I0916, 2018, from https://www.brookfieldengineering.com/.

Briant, J., Denis, J., Parc, G., Rheological Properties of Lubricants, Editions Technip, 1989.

“TM 260.03 Dynamic friction in pin – disk”, https://www.gunt.de/en/products/, 2023.

Gay, C., Leibler, L., 1998, Theory of tackiness, Physical Review Letters, 82, 936-939.

Achanta, S., Jungk, M., Drees, D., 2011, Characterisation of cohesion, adhesion and tackiness of lubricating greases using approach-retraction experiments, Tribology International, 44, 1127-1133.

Harmon, M., Powell, B., Barlebo-Larsen, I., Lewis, R., 2019, Development od a grease tackiness test, Tribology Transactions, 62, 207-217.


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