Process and apparatus for ironing a bolt and bolt produced thereby

摘要

A process of ironing a thread formation shaft portion (wn) of a work for bolt having a cylindrical portion (wk) and the thread formation shaft portion (wn) in axial alignment. The process comprises the steps of supporting the cylindrical portion (wk) of the work (w) in radial directions and in a zero clearance state, and moving the thread formation shaft portion (wn) in the axial direction relative to a shaft portion ironing die (14), the supporting step and the moving step being executed simultaneously. <IMAGE>