Method and apparatus for shearing off of workpieces (am, in particular metallic work (am

摘要

In a method of shearing a workpiece, for example a metal billet or bar (6), and apparatus for carrying out that method, before being subjected to linear shear, the billet is first subjected to substantial torque about an axis (12) perpendicular to the plane of shear. The billet is held by two pivoting arms (9 and 14), the predominant torque of the first stage of the method is achieved by allowing the pivot points of the arms (39 and 38) to slide as the arms turn, and the predominant shear of the second stage is then achieved by arresting (54). The parts of the arms (8 and 13) which grip the workpiece may bear against a fixed surface (36) during the whole operation, so holding the axis of the workpiece to a constant location. IMAGE