Study On LNG Engine Lubricating Oil Composite Additive For Heavy-duty Vehicles

Determining the technical requirements of application of engine lubricating oil composite additives in the LNG heavy duty vehicles, it focus on solving the lubrication problems when LNG engine works in different situations. The better antioxidant properties,dispersion of clean, anti-wear performance and alkaline reserve capacity are required for composite additives. This paper shows the purpose and significance of the study for the subject. It also makes a comparison between disadvantages and advantages of a single agent and compound agent. And the development of a single agent, compound agent and engine oil composite additives in the LNG heavy duty vehicles are shown in this paper. Therefore, we make a project for the research contents and technical route.In the experimental section, the base oil with better viscosity temperature performance is selected first of all. Meanwhile, the light oil with better wear resistance is added into. In order to meet the requirements of CI quality grade of 15W/40 viscosity grades and improve the formula of basic oil, add into non functional additives such as the viscosity index improver and pour point reducer. According to the technical requirements of application that engine oil compound additives in the LNG heavy duty vehicles are equipped with, we can choose functional additives, investigate the sensitivity between additives and basic oil, can also investigate the compatibility among different additives. So we can obtain the synergistic effect,optimum ratio and optimum dosage among them. Based on the selected full formulation experiment of functional additives, we use orthogonal design test method to determine the best combination of full formula with SPSS software to analyze the variance. Then we make a experiment on the adding order of the more important additives to choose the best level combination while we have analyzed various factors that can affect technology of compound agent, after selecting the best formula.Finally, test the LNG engine lubricating oil which formulate by the developed composite additives. The result showed that it is able to achieve the objectives of the proposed requirements. Compared with the single dose of LNG engine lubricating oil—produced by the General Shanxi Petrochemical Company Limited, its oxidation resistance, cleandispersion, abrasion resistance and alkali values are better than the reference oil, and the price also has the advantage than the single dose of LNG engine lubricating oil. In summary, the developed composite additive of LNG engine oil of heavy vehicles is able to achieve the desired goal, reflects the synergistic effect and economical efficiency.