EVALUATION OF ANTI-CORROSION AND ANTI-GALLING PERFORMANCE OF A NOVEL GREASE COMPOUND

Abstract

In this research, the effectiveness of CeO2, Y2O3 and Al2O3 as anti-corrosion and anti-wear additives in commercial grease was investigated. An experimental approach was used to carry on the research. The weight loss of steel coupons protected with a layer of thin grease, with and without the anti-corrosion additives in a corrosive environment was determined. The Friction factor of the grease compound was also evaluated.

The accelerated corrosion tests were performed in a salt spray chamber for an exposure time of 2 weeks (336 hours). The corrosive medium was 5 % wt. of Brine. By varying the weight compositions of the additives (1% wt. and 3% wt.), and comparing the corrosion rates with that of base grease, the effectiveness of various grease additives was evaluated. The result showed that corrosive losses of the test samples can be effectively reduced by adding relatively small amounts of CeOv2, Yv2Ov3 and Alv2Ov3 to the base grease. Corroded surfaces were examined using the Optical microscope to clarify the corrosion mechanism.

The friction test was carried out using a galling tester. The standard test procedure as specified in API RP 7A1 was followed. The result showed that frictional performance of thread compounds can be improved by adding small amounts (1% wt. – 3% wt.) of Yv2Ov3 and Alv2Ov3 as additives.