Antiwear properties of lard methyl esters and rapeseed oil with com-mercial ashless additives
AbstractEffectiveness of lubricity additives in base oils from renewable resources is often different than that in mineral oils. Low erucic Rapeseed Oil (RO) and Lard oil Methyl Esters (LME) were fortified with commercial ash-less additives. A fully formulated additive package with S, P and N containing lubricity enhancers and other func-tional ingredients was evaluated along with two commer-cial high molecular weight esters in Four Ball tribotester. Without additives, both oils showed poor antiwear proper-ties. However, after selecting the most appropriate addi-tives, performance of LME and RO under 150 N load was similar to that of a more viscous commercial lubricant. Under 300N load the lubricity of RO with these additives was significantly better than that of LME or the commer-cial lubricant. This is confirmed by wear scar diameters, torque and temperature increase. Antiwear properties of the selected additive formulations were clearly better than those of a commercially widespread vegetable oil based chain saw lubricant, suggesting that current formulation technology of biolubricants can be significanly improved.