Journal of Oil, Gas and Petrochemical Technology

Journal of Oil, Gas and Petrochemical Technology

Thermal and Rheological Characteristics of Lithium and Calcium Complex Greases

Document Type : Research Paper

Authors
Tarbiat Modares University, Tehran, Iran
Abstract
Grease is a semi-solid lubricant in which the structure is a gel composed of soap fibers arranged in layers. Calcium greases are one of the most economical products but have low thermal stability at high temperatures, for example, having an operating temperature of about 90℃ and a dropping point of 148℃. In this study, we developed a Calcium and Lithium complex grease with adipic and sebacic acid in order to reach a higher thermal performance. The results showed that the dropping points of complex samples are above 250℃. To examine the rheological properties viscosity-temperature curves were studied which revealed that the amount of viscosity for Lithium simple and complex, Calcium complex with sebacic acid at initial and final temperatures of 80℃ and 180℃ was reported as follows: 5370-3240, 6400- 3900, 1200-254 mPa.s, respectively. The study showed that Calcium complex grease with a high dropping point operates softer than Lithium complex grease, so it is more proper for high-speed bearings
Keywords

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