Abstract: The method according to the invention for producing substantially axially symmetrical workpieces by shaping a starting material uses a die and a rotatable tool, the die being provided with a bore along the central axis thereof. Here the starting material is introduced through the bore of the die and pressed in between the die and the rotating tool such that the starting material flows outward from the central axis according to the contour of the die. The workpiece is thus produced in a single operation. Depending on the requirements for the dimensional accuracy and surface quality, mechanical finishing or calibrations are possible. Due to the material flow in the die and the rotation of the tool, shaping forces which are only small in comparison to conventional methods occur here, and so the requirements made of the tools, and so the expense, are reduced.

Abstract: The invention relates to a method for producing essentially rotationally symmetrical, undercut contours on workpieces (13) that can for example be produced by forging or casting, said workpieces having at least one sub-section (14) to be machined with an essentially symmetrical initial contour. The workpiece (13) is braced by the end that is not to be machined in a recess (11) and when in said recess (11) the sub-section (14) of the workpiece that is to be machined is placed against a tool (12). The tool (12) rotates with a constant or variable speed in relation to the sub-section (14) of the workpiece (13) that is to be machined. An undercut contour is thus produced on the sub-section (14) of the workpiece (13) by machining under the axial pressure.