In recent years, some scholars have done a lot of research on the rotary forging process. The rotary forging of spiral bevel gear is a new continuous and locally loaded rotary forming process. It has been highly valued because of its obvious labor-saving, uniform deformation, good surface quality, no vibration and noise, and easy to realize mechanization and automation.
According to the analysis of metal flow and stress-strain state in the contact area of spiral bevel gear ring rolling, it can be seen that the mechanism of spiral bevel gear swing rolling deformation is shown in the figure. Due to the local loading of conical swing head on the blank along the axis, the metal at the contact surface first meets the yield condition and produces plastic deformation. With the gradual expansion of the stress area in the height direction, the absolute value of axial stress gradually decreases, Therefore, the deformation area is mainly concentrated at the upper end of the blank. The deformation area gradually shrinks downward along the axis. When the metal in contact with the surface area is compressed axially, due to the strong constraint of the tangential deformation by the outer end, the area has significant radial elongation deformation, the inner hole shrinks and the outer diameter increases. Because the resistance of inward flow is greater than that of outward flow, the flow boundary is close to the side of the inner hole.
With the continuous local loading of the conical upper die on the annular blank, the above deformation is carried out sequentially along the circumferential direction and gradually accumulated, and finally the overall forming of the spiral bevel gear blank is achieved.