Patent ID: 7882638

Claim:
A process for manufacturing an inner wear surface of a radial bearing for use in a down hole mud motor, the process comprising the steps of: a) providing a cylindrical member having a first outer surface; b) applying a hard facing material on the first outer surface of the cylindrical member so that the hard facing material is fixed onto the first outer surface of the cylindrical member to form a second outer surface of the cylindrical member; c) applying a material layer on the second outer surface of the cylindrical member so that the material layer is fixed onto the second outer surface of the cylindrical member to form a third outer surface of the cylindrical member; d) controlled cooling the hard facing material from a process temperature of about 3500 degrees Fahrenheit to a temperature of 200 degrees Fahrenheit in a material specific time period in the range of two to five minutes; e) machining the third outer surface of the cylindrical member so that a portion of the material layer is removed; and f) drilling out the cylindrical member to expose the hard facing material which forms an inner surface of said cylindrical member in order to form an inner wear surface of the radial bearing.