Open-end spinner rotor

The rotor, for an open-end spinner, has an upper (2) and lower (1) section which are bonded together in a release fitting, so that they can be separated to replace the wear ring (3) in the rotor groove (12) between the rotor sections (1, 2). The wear ring (3) is of ceramic or a hard metal material. The lock between the rotor sections is a threaded screw or bayonet screw structure, or they are held together by magnetic force. The rotor sections can also be bonded together by an adhesive, which can be melted by heat for separation, or they can be locked together in a plug and socket fitting. The upper rotor section is of ceramic or a metal/ceramic compound material, and it can be of material in one piece with the wear ring. The upper rotor section and the wear ring can be separate components. The upper rotor section has a ring edge (11) aligned axially inwards, which extends the entry chamfer (9) and covers the rotor groove (12) at least partially, with a gap between them. The seating fit of the wear ring is formed by a radially outer seating surface (16) where the wear ring lies in a force and positive fit at the radially inwards surface of the rotor lower (1) or upper (2) sections, and with play at the adjacent surfaces (15, 17, 18) of the rotor (1, 2).