Method for machining a functional part

A method for working a functional part that extends in a longitudinal direction, has a lateral surface surrounding a longitudinal central axis of the functional part that extends in the longitudinal direction, and has an end face extending in an axial direction that bounds the functional part at a free end thereof, the method comprising:

• cold-extruding the functional part in an extrusion tool having at least one cold-extrusion punch and a plurality of dies associated therewith;
• removing the functional part from the extrusion tool after the cold-extrusion;
• loading at least a portion of the free end of the functional part into a cavity of a forming tool by pushing the forming tool onto the functional part in the longitudinal direction of the functional part, wherein the cavity of the forming tool is bounded, in a radial direction with respect to the longitudinal central axis of the functional part, by a wall surface of the cavity, which wall surface surrounds and at least partially abuts against the lateral surface of the functional part;
• pressing a re-working punch that protrudes into the cavity of the forming tool and is moveable in a longitudinal direction with respect to the functional part against the end face of the functional part;
• pulling the forming tool off of the functional part in the longitudinal direction over the free end of the functional part, while during at least a portion of said pulling the re-working punch remains pressed against the end face of the functional part;
• and
• forcing a flow of the material of the functional part by the forming tool, during said pulling step.