Effect of Functional Additives on Performance of Internal Combustion Engine Lubricating Oil

In order to improve the quality of lubricants and prolong the life of oil products, functional additives should be added to the base oil. The functional additives of lubricating oil mainly include detergent, dispersant, antioxidant and rust inhibitor. The purpose of present research is to investigate the effect of additives and the dosage of them on the performance of internal combustion engine lubricants. Certain amount of additives were added to the base oil for testing. Detergent T106A and T115B, dispersant T154B, antioxidant T203 and rust inhibitor T705 were selected as functional additives in the experiment. The detergency of the oil was evaluated by coking test. The dispersibility of lubricating oil was evaluated by spot dispersion experiment at low temperature and high. The kinematic viscosity of the lubricating oil was determined according to the method of GB/T265. The infrared spectra of the lubricating oil were used to determine the oxidation value and nitrification value and the flash point of the lubricant oil was measured by flash point meter. The results showed that both detergent T106A and T115B had a good clean ability, and T106A showed better effect than T115B does. In combination with the standard of oil use in internal combustion engine, economic benefit and the reference amount provided by the manufacturer, the optimal dosage of detergent T106A is 2.0 wt%, and the optimal dosage of detergent T115B is 3.0 wt%. The dispersant T154B had good sensitivity at high temperature and also at low temperature, and the optimal dosage was 3.5 wt%. Antioxidant T203 had a good anti-corrosion function, and the optimal dosage was 3.0 wt%. The addition of the rust inhibitor T705 resulted in an overall reduction in the flash point and viscosity of the lubricating oil, and the optimal dosage of rust inhibitor T705 was 4.0 wt%.