The forming process of spiral bevel gear can be divided into three stages. The initial stage of deformation is at the beginning of deformation. The deformation of metal is equivalent to free upsetting deformation, and the forming force is the smallest. In the filling stage of the tooth cavity, the blank begins to fill into the tooth cavity. With the increase of the filling degree of the blank to the tooth cavity, the deformation resistance and friction resistance increase. On the load stroke curve, the load increases with the increase of the upper die stroke. In the filling stage of the tooth cavity, the metal has basically filled the tooth cavity, the blank flow is difficult, and the working load increases sharply.
The figure shows the stroke load curve of spiral bevel gear finite element simulation. By analyzing the figure, it can be seen that in the initial deformation stage, the die contacts the blank surface, and a small amount of plastic deformation occurs to the spiral bevel gear blank. From the beginning to the stroke of 15mm, the load curve rises gently and the deformation force is small. In the tooth cavity filling stage, the spiral bevel gear blank flows to the tooth shape part of the die under the action of external force, and the tooth shape part of the tooth shape die is gradually filled. At this stage, the load curve rises gradually, and the deformation force increases gently and lasts for a long time; In the final filling stage, the tooth shape part of the die is fully filled. At this stage, the load increases with the reduction, and the curve rises almost rapidly, so that the load increases rapidly. When the number of strokes is 18mm, the load has increased to the maximum value, which is because the cavity has been basically filled and the metal flow space has been few. When you continue to squeeze, the metal will produce great resistance. At this time, the load value reaches the maximum, about 26400kn.
To sum up: in the process of tooth profile forming, the distribution of equivalent stress, equivalent strain and other field variables changes greatly, and the metal deformation of each part of tooth profile is also uneven. Therefore, the precision forging of spiral bevel gear belongs to three-dimensional unsteady plastic forming process. Through the numerical simulation of the precision forging process of driven spiral bevel gear, the mechanical deformation characteristics and metal flow law in the forming process are obtained, and the deformation mechanism of the precision forging process of driven spiral bevel gear is revealed, which provides a reliable theoretical basis for the better application of the precision forging process of driven spiral bevel gear in production practice.