The molding process in which a sheet metal disc is clamped against a rotating template and then is forced out against this by means of a pressure roller.
The workpiece is locked between a rotating mandrel  and a tailstock . The mandrel, which is used in place of a lathe chuck is mounted in the machine and its shape is the desired inner contour of the product. Metal Disk, mandrel and tailstock rotates while a rolling tool  applies force as it moves over the workpiece.
This process refines and enhances the metal’s grain structure while improving its smoothness.
Read more: Spin forming of discs