Vegetal Oils as Lubricating Materials

Abstract

The success of vegetal oils is related to their biodegradability and reduced toxicity but a wide use is limited by their insufficient stability in time. Biodegradable oils have ecological advantages, being comparable or better than mineral ones. This paper presents experimental results on oxidation resistance of sunflower oil used as lubrication materials. Tests were done using both unadditivated sunflower oil, for grades as obtained after different steps of manufacturing process and additivated sunflower oil. The authors established that the vegetal oil obtained after the first two steps of manufacturing process presents the most reduced oxidation phenomena and the friction coefficient shows that extraction coars sunflower oils oxidized after 5h and additivated with the 2% ascorbic acid has a the best behaviour to the hydraulic oil H32.