Device for forming a collared calibrated hole in plastically deformable walls

摘要

The punch has a mandrel, which is driven into the wall by pressure. A preformed bore (16) of average diameter is placed in the wall (2). The mandrel is formed as a calibrating mandrel (25) with conically undercut displacement collar (26), with a larger diameter than the bore. The mandrel also has a cylindrical calibrating shaft (27), also with a smaller diameter than the bore.