The numerical simulation of the forging process of “one fire two forging” forming spur bevel gear can reproduce the whole process of metal filling cavity, and analyze the metal flow law and tooth cavity filling mode. By analyzing the velocity field, stress, strain, strain rate distribution and load stroke curve in the deformation process, the rationality of the shape and size design of pre forgings and preforms is verified, and the simulation results are used to optimize them.
Firstly, the three-dimensional finite element simulation models of planetary gear and half shaft gear are established in UG. Then the forging process of planetary gear and half shaft gear is simulated by using the software from-3d. Three pre forging schemes of planetary gears are simulated. The optimal preform size is determined by analyzing the metal strain, strain rate, stress, velocity distribution and load stroke curve under the three schemes. The final forging forming of planetary gear is simulated. The simulation results show that the shape and size of the designed pre forging effectively improve the order of metal filling the tooth cavity. The metal first fills the top of the spur bevel gear, then from the top of the spur bevel gear to the tooth surface, and finally fills the tooth root. It can not only ensure full filling of the tooth profile and avoid insufficient filling of the top of the spur bevel gear forging, but also reduce the forming load by filling the spur bevel gear teeth in the form of upsetting compared with filling in the form of extrusion.
Force, velocity distribution and load stroke curve. The results show that the shape and size of the preform and pre forging designed in this paper can ensure that the tooth shape of the whole spur bevel gear is filled fully and smoothly, the tooth top fillet is full, and there is no corner collapse defect; The fillet of the tooth root is smooth without folding and other defects.