Expanding Spinning（Bulging Spinning）

As shown in the figure, in the process by this method, the spinning wheel penetrates into the large-diameter pipe or cone body, spinning in the inner wall and enlarges the diameter. Due to the tensile deformation of the material, it can not produce large deformation. When the diameter of the blank is too small, so that the spinning wheel can not run into the inside, so the use of this spinning method is limited.           

 Because the deformation of this processing will not be very large, usually a lot of welding parts after rolling are used as the blank.