Rotary heading using a rotary-forging machine with a side roller

Abstract The rotary heading of aluminum blanks was performed with a newly designed rotary-forging machine with a side roller. The position of the side roller was controlled by the stroke of the upper roller in order to prevent non-uniform deformation during the rotary-heading process. An optimum path to control the side roller to obtain a sound product without any defects due to non-uniform deformation can be determined from the condition of volume constancy during the process. Controlling the position of the side roller along the optimum path, the critical aspect-ratio for buckling increases remarkably. The deformation behavior in rotary heading was investigated both experimentally and theoretically. The theoretical predictions were compared with experimental results. The calculated distribution of the contact pressure agrees well with experimental results measured by pressure-sensitive pins. The flow of the metal in rotary heading is clarified also.