US Patent 7882638 Process for manufacturing a bearing

A process for manufacturing a bearing. The bearing may be used in a tool disposed within a bore hole. The process comprises providing a tubular sleeve and applying a hard facing material on the outer diameter of the tubular sleeve so that the hard facing material is fused onto the outer diameter, and thereafter applying a material layer on the outer diameter so that the material layer is fused onto the outer diameter. The method further includes machining the outer diameter so that a portion of the material layer is removed, and then machining the inner diameter so that only the hard facing material is left as an inner diameter. The method further includes machining the outer diameter and the inner diameter in order to form the bearing. In the most preferred embodiment, the method further includes placing the bearing into a housing, and inserting a mandrel into the bearing, and wherein a hard coating of the mandrel abuts the bearing. A mud motor for rotating a bit in a well bore is also disclosed.