Effects of Base Oil Characteristics on the Performance of Automatic Transmission Fluids

摘要

Over the past two decades, the performance requirements for automatic transmission fluids (ATFs) have undergone a significant number of changes in response to mandated legislation by government and regulatory bodies to improve air quality through reduced emissions while providing energy efficiency and "fill-for-life" capabilities. In order to formulate a high performance ATFs, it is now necessary to compliment a strong and well-balanced additive package with a selection of high quality base oils. In this study, performance of several base oils produced from different production schemes as base oils for ATF is investigated. And benefits of dumbbell blending approach using hydrocracked base oil in ATF design are discussed. Hydrocracked base oil shows superior performance in viscometrics and oxidation stability solvent refined or hydrotreated base oils. And it is also shown that dumbbell blending of base stocks gives benefits in low temperature performance of ATF. Additionally, hydrocracked base oils with extremely low pour point gives more benefits in low temperature performance of TATF.