A process is disclosed for forming metallic lid bordering rings (20; 20a, 20b, 20c, 20d, 20e) with an inside opening (21) and a ring-shaped profiled border (20a, 20b, 20c, 20e). A cylindrical blank (10, VR) placed in the centre of several ring-shaped, concentrically joined tool segments (1 to 7) is pushed axially downwards (v0) by a outer tool segment (1) and deformed in a radial direction (v0') over a ring-shaped deflecting lip (5a) of a segment tool (5) located further inward in the radial direction among the concentrically joined tool segments (1 to 7). An upper segment tool (2) is held above the deflecting lip (5a) to define a gap (S) into which the blank (10; VR; HR) radially deformed (v0') inwards is pressed. This avoids the formation of cuttings inside (21) the thus produced lid bordering ring (20).