Research On Cylindrical Roller Bearing Crown And Mechanical Property

This work is supported by the National Natural Science Funds of China (Grant number.51005031).In general, the cylindrical roller bearing are used heavy-load and high-precision working condition. Failure is easily occurred in cylindrical roller bearing for excessive pressure peak at the end of rolling element, which is called’edge loading’. Therefore, the profile of the roller is designed. The crowned roller can improve stress concentrations and avoid bearing early failure. In this study, the crowned shape and size of cylindrical roller are accomplished based on contact analysis and mechanical property of the cylindrical crowned roller bearing is also researched.Firstly, a solution method for finite length cylinder contact is built with slice method. The deformable coordination of slice is established by influence coefficient method. Crowned size, contact stress and elastic approach of single roller with four common crowned profile are calculated by the mathematical model. The result is also verified by finite element method. Parameters of logarithmic profiles are optimized based on the model.Secondly, elastic approach between bearing rings and rollers with different crowned shape,size and external load are calculated. Single crowned roller’s load-elastic deformation function are got by nonlinear fitting using MATLAB software. Different crowned shape rollers’contact stiffness expression are derived based on the above function.Then, plug stiffness expressions into the bearing load distribution calculation procedure. Load distribution of the cylindrical roller bearing is got. The influence of crowned shape on load distribution of bearing with different radial clearance is analyzed, elastic approach between inner and outer ring of bearing with different crowned shape, size and external load are got. Bearing load-elastic approaching curve is drawn based on which the influence of crowned factors on bearing stiffness properties are analyzed.Finally, the contact model between tilted crowned roller and rings is established., which could be used to study influence of angle of inclination, roller profile and crowned shape on tilted contact. Dissymmetric roller profile is designed to eliminate eccentric load effect which is appeared on tilted contact and difficult to avoid. The crowned shape is made up of linear function eliminating eccentric load effect and exponential function avoiding edge loading. The contact stress distribution is improved when dissymmetric roller profile is used.