Abstract: The invention disclosed hereunder is a process and a device for the preparation and formation of a plastic weld connection between a workpiece (13) and a second component to be attached thereto by heating by means of a heating device (12). If force is applied, the heating element (12) tends to deform the contact surface especially in the case of hollow, thin-walled workpieces such as plastic containers. So far, methods were disclosed for the measuring of the degree of deformation by means of a sensor, subsequently readjusting the position of the heating device according to the determined deformation. The invention disclosed here under dispenses with any measurement of deformation, instead using an elastic element which automatically readjusts the position of the heating element (12) in the case of deformation of the workpiece (13) to effect a pre-load between the heating device (12) positioned at the contact surface of the work-piece (13) and the workpiece (13).

Abstract: A boring apparatus which includes a rotatable cutting head used to cut a hole in a workpiece. The cutting head is mounted on an axially movable support, and is rotatable about and reciprocally movable along the axis between a forward cutting position, to engage and cut the workpiece, and a rearward position spaced from the workpiece. Cutting is performed by a cutting blade which is spaced radially from the axis, and which is movable relative to the rest of the cutting head by a blade advance mechanism. During cutting operation, the blade advance mechanisms move cutting blade both forwardly and radially inwardly through the workpiece wall, in the same direction at which the blade is inclined. The hole is thus formed by lowering the cutting head and then rotating the cutting blade as the blade advance mechanism moves the blade at an angle through the workpiece.