Abstract: A grinding disc device for a grinding apparatus is described, having at least one grinding layer and a carrier disc fixedly connected to the grinding layer. The grinding layer has at least one connection surface (FV) connected to the carrier disc and forms an abrasive grinding surface (FS) lying opposite the connection surface (FV) and facing away from the carrier disc. The carrier disc made of a plastic material is produced by injection molding and is connected immediately and directly to the connection surface (FV) of the grinding layer, wherein the plastic material of the carrier disc is sprayed by injection molding immediately and directly onto the connection surface (FV) of the grinding layer, such that the carrier disc and the grinding layer are connected to one another in a material-locking manner.

Abstract: A backing plate for an abrasive flap wheel has a sunk inner part and an outer flange. The sunk inner part has a hub which is provided with a location hole having an internal thread. The internal thread serves to fasten the backing wheel to the threaded shaft of a driving machine.

Abstract: The abrasive flap wheel (1) has a backing plate (2) which comprises a sunk inner part (3) and an outer flange (4). The sunk inner part (3) has a hub (7) which projects toward the front side (3a), i.e. toward the side of the abrasive flaps, and is provided with a location hole (8) and an internal thread (9). The internal thread (9) serves to fasten the abrasive flap wheel to a corresponding driving machine.