Abstract: Polycrystalline diamond wear surfaces in bearing structures are maintained at temperatures that prevent thermal degradation in spite of exceptionally high loads. This temperature control is accomplished by segmenting the diamond wear surface to provide interrupt channels through which the energy build-up at the diamond wear surface is maintained below the thermal degradation level. Cooling fluid may be caused to flow through the interrupt channels, the higher the velocity of fluid flow around the diamond bearing surface, the greater the cooling effect.

Abstract: Bearing rings containing PCD faced bearing inserts are mounted adjacent tungsten carbide radial bearing surfaces at the ends of respective bearing sleeves attached to the drive shaft of a down hole well drilling motor, thereby preventing excessive wear at the extremities of the radial bearing surface in controlled and steerable drilling applications.

Abstract: A unitary sleeve mounts both thrust and radial bearings, the radial bearing being fabricated of macro-crystalline tungsten carbide powder and cemented tungsten carbide cobalt chips in a recessed area on an elongated extension and the thrust bearing comprising a ring carrying diamond inserts residing in through holes, the ring and inserts being brazed on a hub at the thrust head end of the extension.

Abstract: A structure and method for attaching bearing inserts including a bearing ring having through holes therein into which said inserts are press fitted and an underlying brazing ring, which, when heated, attaches the bearing inserts to the bearing ring and the bearing ring and inserts to an adjoining structural member.