A bush bearing and a scroll compressor including a bush bearing are provided. A boss of an orbiting scroll may be inserted into and coupled to a boss coupling groove of a rotational shaft, and thus, an outer circumferential surface of a bush bearing may wholly contact an inner circumferential surface of the boss coupling groove, thereby decreasing wear of the bush bearing. Further, friction loss in the bush bearing may be reduced, and thus, compression efficiency and reliability may be enhanced, noise may be reduced, and material costs may be reduced. Furthermore, despite that the bush bearing is formed in a ring shape and press-fitted to the boss, as the bush bearing may be formed of a plastic material having an ether ketone bonding in consideration of a thermal expansion rate, an elongation, and a press-fit range, the bush bearing may be effectively prevented from being detached from the boss, thereby enhancing a reliability of a compressor.

Rotors formed by an additive manufacturing process are presented. In one example, a rotor includes a monolithically formed rotor body and a plurality of helically arranged lobes formed from a first material, wherein each of the plurality of lobes defines an internal cavity between an outer surface and a central aperture.