Abstract: A downhole seal system for roller cone drill bits includes a seal gland having a width larger than it depth. In one implementation, the seal gland includes a protrusion along its base on which a seal element seats. The seal element is a single, annular seal element with a recess formed therein so as to define two lobes. The seal element seats in the gland so that the recess engages the protrusion. The lobes function as separate seal elements, although they are a single unitary seal element disposed in a single gland.

Abstract: A drill bit of the type used to drill a wellbore in the earth can comprise a bore formed in the drill bit, and a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between sections of the bore in the drill bit. The plug can comprise a spherically-shaped member. The plug can comprise a floating plug sealingly and reciprocably disposed in the bore, whereby pressure in the different sections of the bore on respective opposite sides of the plug is substantially equalized.

Abstract: A drill bit of the type used to drill a wellbore in the earth can comprise a bore formed in the drill bit, and a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between sections of the bore in the drill bit. The plug can comprise a spherically-shaped member. The plug can comprise a floating plug sealingly and reciprocably disposed in the bore, whereby pressure in the different sections of the bore on respective opposite sides of the plug is substantially equalized.

Abstract: Roller cone drill bits operable to form a borehole. A number of support arms may extend from each drill bit. A cutter cone assembly may be mounted on each support arm. A number of cutting elements or inserts may be disposed on an exterior surface of a cone assembly. A lifting surface may be formed on each support arm extending between a leading edge and a trailing edge of each support arm such that the lifting surfaces directs cuttings upward in a borehole. A wedge shaped portion may be formed on each support arm proximate the lifting surface and the trailing edge. An inlet to each lifting surface may be formed on the leading edge of each support arm.

Abstract: Roller cone drill bits operable to form a borehole. A number of support arms may extend from each drill bit. A cutter cone assembly may be mounted on each support arm. A number of cutting elements or inserts may be disposed on an exterior surface of a cone assembly. A lifting surface may be formed on each support arm extending between a leading edge and a trailing edge of each support arm such that the lifting surfaces directs cuttings upward in a borehole. A wedge shaped portion may be formed on each support arm proximate the lifting surface and the trailing edge. An inlet to each lifting surface may be formed on the leading edge of each support arm.

Abstract: A roller cone jet-type drill bit with nozzles which direct collimated streams of mud at different angles, to sweep different radii of the hole bottom.

Abstract: The present invention allows the load carrying capability of a drill bit journal bearing or bushing to be increased. The present invention increases the length of the journal bushing by using the ball bearings to retain the journal bushing at a desired location between the journal and the cutter cone assembly. Normally, the journal bushing is retained by a flange formed on the interior surface of the cutter cone assembly. In the present invention, this flange is removed, and the ball bearings are used as a retention device for the journal bushing. With the flange removed, the length of the journal bushing may be increased.

Abstract: The present invention allows the load-bearing capabilities of a drill bit thrust flange to be increased. The invention utilizes a thrust flange that is larger than the inside diameter of an associated drill bit journal bushing. The thrust flange may extend past the inside diameter of the journal bushing up to a distance equal to two times the thickness of the journal bushing. The invention may also utilize a thrust washer that is disposed adjacent the thrust flange to assist in bearing loads applied to the thrust flange.

Abstract: In the method of manufacturing case hardened rock bits formed of a previously known conical profile for containing spaced apart cutter inserts in a common circumferential row about the cone, carburizing is applied uniformly over the entire conical surface of the cutter blank. Without removing any of the applied carburizing composition elsewhere, the compact lands are counterbored of diameter slightly larger than the socket cavity to be drilled, and to a depth below the carburized case so as to remove the carburized case thereat. The cutter blank is then hardened after which the insert cavities are drilled concentrically through the previous counterbores followed by a pressing of the individual inserts in an interference fit into the cavities. This results in continuous uninterrupted case hardening in the land areas between adjacent inserts. Also disclosed is a rock bit formed in accordance with the aforesaid method.

Abstract: A tri-cone rotary rock bit having true rolling conical cutters of different cone angle and with each cutter having a plurality of intermediate annular rows of cutting projections for disintegrating the borehole bottom. Such projections in the intermediate rows being true-rolling about a bottom distinct from the bottom cut by the projections on the remaining intermediate annular rows of the cutting projections of each cone are also at distinct separate distances from the center of rotation of the bit to produce a borehole bottom profile having concentric rows of crests and valleys.