Method of cold bending of hollow workpieces

摘要

The workpiece is clamped in at one end in a support (2) and closed at the other end by a cap (4). A bending force is exerted on the workpiece by a jaw (4) while the workpiece is supported by a die (3) which has a radius at which the workpiece is to be bent. The workpiece is filled, from the end at which it is clamped in, with liquid, either over the area which is to be bent or over its whole length. The fluid may be placed under pressure of between 200 and 600 bar, preferably between 250 and 350 bar.