The Flowdrill comes into contact with the material using relatively high axial pressure and rotational speed. The generated heat makes the material soft and malleable enough to be formed and perforated. As the Flowdrill pushes into the material, some of the displaced material forms a collar around the upper surface of the workpiece. The rest of the material forms a bushing in the lower surface of the workpiece. All this happens in a matter of seconds. The resulting collar and bushing can be up to 3 times the original material thickness. The diameter of the bush is accurately determined by the cylindrical part of the Flowdrill tool.
