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Tribometric evaluation of rubber (Hevea brasiliences) seed oil lubricant in upset forging was carried out. Upset forging was simulated with ring compression tests using Plasticine as model material and the rubber and reference oil samples as lubricant. The oils were applied to various die/ring surface combinations as they were compressed in the California Bearing Ratio (CBR) machine. Results show that friction factors for rubber seed oil ranging from µ=0.20 to µ = 0.577 compare favorably with the values for reference mineral base oil (0.29-0.42). Friction factors obtained from ring compression tests for the rubber seed oil are within the range of natural oil lubricants (groundnut oil; 0.072-0.5, palm oil;. 0.3, palm kernel oil; 0.084 and sheanut oil; 0.092). Rubber seed oil can therefore be used as a substitute for mineral base oils that are currently in use as lubricants in upset forging. Industrial organizations will derive immense benefit from this source of environment friendly, biodegradable and low toxicity oil lubricant.

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Comparative evaluation of the effect of fatty acids profile on the thermal properties of ethyl esters of yellow oleander (Thevetia peruviana) oil and Groundnut (Arachis hypogiaea) oil as biodiesel feedstock was carried out. Chemo-physical properties of the oils and their fatty acid profile were determined. Ethyl esters of the oils were obtained by transesterification using ethanol with potassium hydroxide as catalyst. Chemo-physical properties and fatty acids profile were determined for the biodiesel produced. Results showed that the chemo-physical properties obtained for the ethyl ester of yellow oleander oil such as flash point (48.67 0 C), fire point (86.33 0 C), cloud point (12.3 0 C), pour point (2.33 0 C) and free fatty acids (0.65%) were consistent with ASTM stipulated standards for fuel grade biodiesel. The fatty acids for yellow oleander were predominantly 7.337% stearic acid (2,696.12J/kg), 18.618% palmitic acid (2384.76J/kg), 49.615% Oleic acid (2657.4J/kg) and 14.22% linoleic acid. The saturated fatty acids were capable of readily releasing their heat content during combustion. Groundnut oil gave similar result except 66.15% oleic acid which put it ahead of yellow oleander's 49.61%. On the basis of thermal properties, groundnut oil was better but the drawback as biodiesel feedstock lies in its high free fatty acids and the pressure on it as a staple crop. Use of yellow oleander biodiesel would reduce this pressure and extend the use of this ornamental crop.