Abstract: In an open-end rotor spinning apparatus, the driven rotor shaft (2) of the spinning rotor (1) is mounted by means of bearing members (20) for rotation in a casing (3) which is inserted into a mounting on the machine. The replacement of the spinning rotor (1) together with the bearing casing (3), without exerting a load on the bearings, is made possible by a flange (60) which is disposed on the bearing casing (3) and which extends along the rear side of the spinning rotor (1) and projects at least over the major diameter of the spinning rotor. During replacement of the rotor, the flange (60) serves as a handle, and in normal operation it serves as an additional cooling means for the bearings. By means of a ring (61) mounted on the flange (60), it is possible to form a casing (6) which is open at the front and which, with slight clearance, surrounds the outside contour of the spinning rotor (1) and reduces the consumption of energy.