Tribological behaviour of refined bleached and deodorized palm olein in different loads using a four-ball tribotester

Vegetable oil is one of the bio-oils that have been promoted to replace petroleum-basedproducts due to its eco- friendly characteristics. palm oil has high productivity rate, and so it could fulfilthe demand for a bio-lubricant. in this paper, the influence of the normal load on friction and wearperformance were investigated for a rbd palm olein and compared with paraffinic mineral oil using four-ball tribotester. the normal load was varied from 30 kg to 60 kg. all experimental works were conformingto astm d 4172. the results exhibited that the rbd palm olein has lower coefficient of friction comparedto paraffinic mineral oil. however, the wear scar of ball bearings lubricated with rbd palm olein showedlarger diameter compared to paraffinic mineral oil. as a conclusion, rbd palm olein has better performancecompared to paraffinic mineral oil in terms of capability to reduce friction.