Abstract: An earth boring bit having an improved two piece bearing construction using an internally tapered and threaded, cantilevered bearing lug extending obliquely inwardly and downwardly from a leg carried by the body of the bit. An internally tapered and threaded bearing sleeve is made up on the lug, and includes a mouth that engages a shoulder on a base region of the bearing lug. The mouth of the sleeve has a minimum radial thickness such that the sleeve may be made up to a selected minimum torque. The bearing sleeve has a length greater than that of the treaded portion to define a thick walled inner end region to receive a resilient retainer ring in a groove that provides a minimum section over the threads on the interior of the sleeve. The sleeve is boronized to achieve wear resistance in a manner that does not substantially reduce strength.

Abstract: An improved method for hardfacing tool joints for earth boring drill pipe. Annular bands of hardfacing are applied by an apparatus that creates an arc between a consumable steel wire and the tool joint. The steel wire is reciprocated across the width of the band as the tool joint is rotated. Granules of tungsten carbide flow by gravity from a hopper into the weld puddle. The flow of granules into the puddle is stopped just prior to reaching the tie-in point. The arc continues a short distance, creating an overlapping protuberance at the tie-in that is free of granules at the surface. This protuberance can be easily ground smooth with the remainder of the hardfacing.

Abstract: In an earth boring tool an improved sintered tungsten carbide insert and surface conditioning method to improve retention within an interferringly sized hole and to decrease the frequency of fracture of the inserts. The insert has a randomly varied surface finish that is obtained from abrasive treatment with particles having hardness greater than 9.0 on Mohs' Scale. The particles are selected from the class consisting of silicon carbide, boron carbide, boron, and diamond. The resulting surface has asperities varying from a maximum value, smaller than that formed by grinding, to a minimum value, larger than the mat finish obtained by abrading with aluminum oxide.

Abstract: Disclosed herein are treatments for the manufacture of wear resistant steel surfaces, which are carburized, boronized, quenched and tempered for extreme surface hardness, with a strong, tough supporting base that minimizes fracturing of the brittle boronized case.

Abstract: Disclosed herein is a method of selectively boronizing of the surface of ferrous metal that is characterized by applying to such area as is not to be boronized a coating consisting essentially of finely divided titanium dioxide, finely divided carbonaceous material and an anhydrous binding agent in effective amounts to form a boronizing resist having boronizing resistance during boronizing, then boronizing the ferrous metals at a temperature at which the coating forms the boronizing resist and subsequently removing the boronizing resist. Also disclosed are compositions for preferred applications of the coating and additional details on preferred embodiments.

Abstract: Disclosed herein is an improved method of finishing a steel article having a carburized and boronized case. The article is carburized to a selected depth then finished to a smoothness which is smoother than the desired final finish. The article is then boronized, hardened and tempered. Further finishing is unnecessary.