Punching process where a hole is punched in the workpiece with an inserted mandrel. Beskrivning The process A mandrel is inserted and positioned under the punch, which is then pressed against the workpiece with an applied pressing force. Depending on the design of the workpiece, one or more subsequent strokes is needed. When punching the welded tubes should be provided with a slot die so it does not wedge against the slit. This also avoids cracking of the welding seam which would degrade the result. To punch out a hole the material is subject to shearing between the punch and die. During the punching process material is displaced and then loosen completely by material failure. This gives both the punched detail and bore, the typical cut surface seen in punching operations i.e., smooth surface where the material has slipped and a rougher surface where the failure occurs. In cases where the tools designed to carry out compression forming so deformed sheet by plastic deformation. Tube punching with mandrel Process films
