Research On The Double Disc And Eccentric Straight Groove Lapping Method For Cylindrical Roller

Bearing is a very important basal assembly unit of rotating machines. And cylindrical roller is not only an important part of roller bearing, but also the vulnerable part of roller bearing. The production quality of rollers directly influences the bearing performance, such as rotation accuracy, bearing capacity, running noise and seismic behavior. Because in the traditional method for lapping cylindrical roller the consistency and lapping efficiency is low, it is hard to meet the requirement of high precision cylindrical roller bearing for lapping accuracy and efficiency. To solve these problems, a new method for cylindrical roller lapping, namely double disk and eccentric straight groove lapping method has been put forward in this paper.Double disk and eccentric straight groove lapping method is chracterised that double disc is adopted in the structure. One disc is flate and the other disc has an eccentric straight groove. In the lapping process, the workpiece do spin and translational motions along the straight groove. The method has the ability of mass production, can rapidly improve the cylindricity and size consistency of the workpiece, improve the machining efficiency, and reduce the processing cost. To verify the feasibility of this method, this paper has completed the following work:Firstly, in this paper the motion of cylindrical roller under the double disk and eccentric straight groove lapping method has been analyzed, and the simplified model for double disc and eccentric straight groove lapping method has been established by using the finite element simulation software. The influence of friction coefficient between lapping disc and cylindrical roller and straight groove section parameters on cylindrical roller's spin motion under the double disk and eccentric straight groove lapping method has been analyzed,and the requirement for lapping discs' materials and straight groove section parameters under the method has been determined.Secondly, according to the analysis results of the finite element simulation, nine kinds of materials have been combined with cylindrical roller respectively, and a series of friction and wear experiments have been conducted on the friction and wear test machine. Polymethyl methacrylate and polytetrafluoroethylene have been selected as the optimal combination of the lapping discs' materials for the double disk and eccentric straight groove lapping method through the analysis of results of the friction and wear experiments.Finally, in this paper the cylindrical roller's lapping prototype based on the principle of the double disc and eccentric straight groove method has been built by using the selected lapping discs' materials, and the cylindrical rollers' preliminary lapping experiments have been completed. According to the experiments' results the feasibility of the double disk and eccentric straight groove lapping method has been verified.