Friction Properties And Mechanism Of High-speed Bearing Grease Under Elastohydynamic Lubrication

Under elastohydrodynamic lubrication state, the friction characteristics of thegrease have a great influence on the dynamic performance of rolling bearings. Atpresent, the information of modeling real bearing friction coefficient of the lubricantunder complex condition (elastohydrodynamic lubrication) are rare. Because underelastohydrodynamic lubrication the friction coefficient of the grease measuredignoring the state of actual elastohydrodynamic contact area is not exact. Thusmeasuring friction properties of lubricant under condition of simulating the actualworking contact area is necessary. Research of the project has an important influenceon the design quality and life of bearing in our country, the accurate prediction of thebearing friction torque and the lubricating property, ensuring the precision and lifeof the mechanical equipment. And it also provide important data for the study of thedomestic lubricant. It will lay the foundation for elastohydrodynamic lubricationtheory and lubricant rheology development.In this study, a traction device has been used to evaluating the tractioncharacteristics of grease LGLT. Through the analyzing the influence of the load andthe rolling speed on the fiction coefficient, the rule of the influence of workingconditions on the friction coefficient is gained. With the mathematics knowledge, thefriction coefficient calculation model of high-speed bearing grease is built and thefriction mechanism of grease is analyzed and high-speed grease rheological model isestablished. Finally the performance of the foreign high-speed bearing grease anddomestic high-speed bearing grease7007,7018are compared. The load turning pointof the grease7007is smaller than7018and LGLT. When load is lower than69N, thefriction coefficient of grease7007is significantly smaller than the other two kinds ofgrease. When load is higher than69N, the friction coefficient of grease7018issignificantly smaller than the other two kinds of grease. The influence of load tofriction coefficient changes from strong to weak:7007>LGLT>7018.