Research on an Analytical Method for the Forming Force of External Spline Cold Roll-Beating

To determine the force and energy parameters of cold roll-beating of external splines, the characteristics of the deformation zone in cold roll-beating are analysed. The geometric dimensions and position of the deformation zone change with the movement of the roller, the contact arc, and the reduction are very small, and there is an incomplete deformation zone in the initial stage of cold roll-beating. A discrete analytical method for calculating the unit pressure and deformation force is proposed, and the cold roll-beating process is discretized into an infinite number of cold-rolling processes with complex sections. The discrete analytical model of unit pressure and deformation force is established, and the unit pressure value and its distribution characteristics are determined. To verify the discrete analytical model, a finite element model of cold roll-beating is established, and the forming force is calculated. A horizontal milling machine is modified to carry out the cold roll-beating experiment, and the forming force is measured. The predicted results of the discrete analytical model are compared with the simulation and experiment results. The results show that the maximum error of radial force compared with the simulation and experiment results is about 7 % and 4 % respectively, and the variation curve of radial force is basically consistent, but the time of a cold roll-beating process is slightly shorter. The discrete analytical model correctly predicts the magnitude and change process of cold roll-beating forming force.