Abstract: A rolling cone cutter earth boring bit is provided with a load carrying bearing surface that can be renewed during the earth boring operation. A canister bearing element is positioned between the bearing pin and the rolling cone cutter. The rolling cone cutter rotates about the canister bearing element in a first direction during normal drilling operations. The canister bearing element has directional stops on its inside surface. These directional stops engage directional stops on the bearing pin and prevent rotation of the canister bearing element during normal drilling operations. The bearing surface can be renewed by reversing the direction of cutter rotation thereby disengaging the canister bearing element from the directional stops and allowing it to rotate in the opposite direction until a new bearing surface is in the load area.

Abstract: A device for preventing penetration of dust from the outside inwardly into an annular gap between a cutter arm of a cutting machine and a rotatable cutting head carried on said arm, said cutting head having an interior space containing lubricating oil, said device comprising a first seal closing off said interior space and located in said gap, a second seal located in said gap outwardly of said first seal, the grease flow resistance of said second seal in the outward direction being less than the grease flow resistance of said first seal in an inward direction, and a pressurized grease supply line arranged within said cutter arm opening into said gap at a location between said first and second seals whereby during operation of the cutting head grease flows outwardly through said gap and prevents entry of dust into said gap.

Abstract: A drilling bit for drilling earthen material such as an oil well rotary cone drilling bit, which includes means for preventing foreign particles such as sand, rock cuttings, etc., from reaching the rotational bearings of the bit cones. This end result is principally achieved by means of a centrifugal slinger disc or wall which is positioned in external concentricity with the drill bit cone bearing, and operates to drive granular particles away from the bearings, thereby preventing such particles from reaching these bearing surfaces. The granular particles are driven by the slinger action through a series of apertures forming a channel running out to a peripheral region of the bit cones. A channel continuation is also provided for lubricating fluid, which may comprise ambient water or oil placed in chambers surrounding the bearings, this channel providing access for such lubricating fluid inwardly to the bit cone bearings.

Abstract: A sealing system for a rotary rock bit retains lubricant inside the bit and acts as a barrier to the pulverized cuttings and other materials in the borehole to prevent the materials from entering the bearing area through the cone mouth opening of the rolling cone cutter. A protecting ring is positioned outside of an elastomer seal element. Both the protecting ring and the elastomer seal element are positioned in the cone mouth opening. The protecting ring is positioned in the cone mouth opening with a slight interference fit. This allows the elastomer seal element to be protected from the hostile drilling environment and increases seal life. The protecting ring retards materials in the borehole from contacting the seal element. The sealing system is provided without reducing the bearing capacity of the bit's bearing system.

Abstract: A removable shirttail of an earth boring tool, such as a hole opener, protects the seals and bearings of an associated cutter. In one embodiment, the shirttail attaches to a journal or mounting shaft of the cutter by threaded fasteners. In an alternate embodiment, different threaded fasteners that attach the journal to an associated leg of the tool cooperate with the cutter and the leg to clamp the shirttail between the journal and the leg. A wedge-shaped boss of the shirttail faces the wall of the bore being opened. A V-shaped saddle in the boss receives a complementary lug of the journal. The lug of the journal also mates with a complementary notch of the leg to prevent journal rotation. The removal of the theaded fasteners that attach the journal to the leg allows spacers or shims to be withdrawn, which in turn permits the cutter, journal, and shirttail to be moved along the journal axis to clear a nose of the journal from a bore in a central body of the tool.

Abstract: A rotary roller bit for drilling earth and rock formations, having a main body and three legs extending outwardly therefrom. Each of the legs carries a conical roller cutter with internal bearings and there is a seal around the periphery of the top of the roller cutter. The periphery of the roller cutter is spaced from the adjacent portion of the leg so as to provide a jet slot for the discharge of air. Adjacent the slot and radially inwardly is an air chamber which is formed between an annular surface of the leg and a seal ring. The air chamber is substantially greater in its dimension axially of the roller cutter and air is supplied to it under sufficient pressure to cause a jet of air to flow from the jet slot at a sufficient rate to prevent the entry of rock particles and dirt into the roller cutter.

Abstract: A roller bit for rock drilling comprising a body having at least one stub axle and a geared cutting element rotatably mounted on said stub axle. The stub axle and cutting element have confronting spaced raceways for a plurality of rolling elements. A shoulder is formed adjacent one end of the raceway in the stub axle to axially fix the rolling elements in one direction. A locking ring is mounted in the cutting element having an abutment shoulder confronting the opposite axial end faces of the rolling elements and axially fixing the rolling elements in a direction in the opposite direction. The locking ring has an outer cylindrical peripheral surface engaging in a complementary cavity in the cutting element adjacent the raceway surface therein. The locking ring has a seat for mounting a resilient sealing member engaging the stub axle adjacent the raceway therein connected in the mounted state to the stub axle.

Abstract: A sealing system acts as a barrier to the drilling fluid, pulverized cuttings and other materials in the borehole preventing the materials from entering the bearing area of an earth boring cutter and retains lubricant inside the bearing area. At least one bearing pin extends from the body of an earth boring bit and a rolling cutter is mounted on the bearing pin. A seal assembly is located between the mouth of the cutter and the bearing pin. The seal assembly includes an "O" ring and a washer ring. The washer ring has a semi-circular or semi-elliptical cross section.

Abstract: A nutating earth drilling bit which is adapted for use in drilling systems in which the drilling fluid and cuttings are transported from bit to surface through the interior of the drill string. The nutating bit is provided with a toroidal cutting member and a longitudinally extending annular shank, both of which have longitudinally extending passageways aligned with one another and in flow communication with the central return conduit of the drill string. The cutting member of one embodiment has a segmented cutting web at its lower end which divides the central passageway into three separate fluid return channels. Another embodiment drills an annular hole face around an uncut earth core, the core being permitted to rise into the shank member where it is broken into short segments by a core breaker.

Abstract: A cutter with a replaceable cutting element is adapted to be mounted upon the rotary head of an earth boring machine or upon the body of an earth boring bit. A rolling cutter shell is mounted upon the rotary head or the bit for rotary motion to roll along the formations being cut. The rolling cutter shell includes first and second ends with an annular receiving surface between the ends. Replaceable cutting means substantially encircle the rolling cutter shell for contacting the formations and forming a hole therein. The replaceable cutting means include an inner surface that mates with the annular receiving surface of the rolling cutter shell. Locking means securely lock the replaceable cutting means to said rolling cutter shell and draw the inner surface of the replaceable cutting means into engagement with the annular receiving surface of the rolling cutter shell.

Abstract: Lubricant is circulated from a lubricant reservoir to the bearings of a rotary rock bit and back to the lubricant reservoir by a lubricant circulation system that is operated by rotation of the cone cutter upon the bearing pin of the bit. A spiral groove system in the inner surface of the cone cutter operates as a viscous or ram pump when the cone cutter is rotating against the corresponding bearing surface of the bearing pin and provides the pumping action for circulating the lubricant. A seal is positioned between the rolling cone cutter and the arm of the bit to maintain lubricant in the bearing area and to prevent fluid in the borehole from entering the bearing area. A lubricant reservoir is located in the bit body. A first passage connects the lubricant reservoir with the bearing area to channel lubricant from the lubricant reservoir to the bearing area. A second passage extends from the bearing area to the lubricant reservoir to allow lubricant to be channeled back to the lubricant reservoir.

Abstract: A drilling bit for drilling earthen material such as an oil well rotary cone drilling bit, which includes means for preventing foreign particles such as sand, rock cuttings, etc., from reaching the rotational bearings of the bit cones. This end result is principally achieved by means of a centrifugal slinger disc or wall which is positioned in external concentricity with the drill bit cone bearing, and operates to drive granular particles away from the bearings, thereby preventing such particles from reaching these bearing surfaces. The granular particles are driven by the slinger action through a series of apertures forming a channel running out to a peripheral region of the bit cones. A channel continuation is also provided for lubricating fluid, which many comprise ambient water or oil placed in chambers surrounding the bearings, this channel providing access for such lubricating fluid inwardly to the bit cone bearings.

Abstract: A rock bit for drilling hard formations has a bit body with a plurality of rolling cone cutters mounted on it for rotation with rotation of the bit body. The cutters each have a plurality of recesses in their outer surfaces and a tungsten carbide insert is interference fitted into each of said recesses. A large diameter rock bit has such inserts larger than about 3/4 inch diameter and a cavity is provided in the cylindrical base of such an insert. The cavity has a volume in the range of from about 15 to 30% of the volume of the cylindrical base and extends into the cylindrical base a distance of at least about 40% of the diameter of the base. The depth of the recess is more than half of the length of the portion of the insert that grips the recess in which it is inserted. Large savings in expensive tungsten carbide can be made without decreasing performance of the tungsten carbide inserts.

Abstract: A roller-type rock bit has a body which fits into a drill hole and is provided with inwardly directed spindles about which cone-shaped cutters revolve. Between each spindle and its cutter is a tapered roller bearing, a flat thrust bearing, and a sleeve-type radial bearing arranged in that order from the large end of the cutter. The raceways of the tapered roller bearing converge toward the small end of the cutter, and that bearing is unitized by a thrust rib located on the spindle opposite the small ends of the rollers and a rib ring which fits into the cutter opposite the large diameter ends of the rollers. Thus, a major portion of the radial load encountered in drilling is taken by the tapered roller bearing, as well as a significant portion of the thrust load, with both of those loads being transferred between the raceways generally transversely through the tapered rollers.

Abstract: A self-advancing conical boring tool with a tapered frame for supporting roller cutters, each of which has a frusto-conical body with a plurality of teeth randomly disposed about its periphery. Each roller cutter is constrained within a pair of thrust bearings and a pair of self-aligning spherical roller bearings for free rotation about an axis that is both oblique and skewed relative to a longitudinal axis of the tool. A flexible diaphragm is captively held to the frame proximate each roller cutter and forms a pressure compensated chamber for a bearing lubricant, one face of the diaphragm being adjacent a thrust bearing and the other face of the diaphragm being exposed to the environment through a vent.

Abstract: Rock bit for drilling holes in the earth's crust which can be connected to driving means and being provided with supports or rock bit legs in which rotatable cutting elements or cutter cones are journalled, wherein a rock bit support comprises a removable part to which the bearing outer race ring is connected, the support part being a regularly shaped spatial body having edges which, in the assembled position, are situated in boundary planes of the support or rock bit leg.

Abstract: A three cone rock bit comprises legs and freely rotating cutters mounted on the same. The angle .alpha. between the projections of the rotational axes of two adjacent cutters on a plane perpendicular to the axis of the bit is more than 120.degree. but less than 170.degree.. A flow nipple to supply drilling fluid is provided in the bit, the outlet thereof being positioned between said two cutters.

Abstract: An improved lubricant pressure compensator system for an earth boring drill bit for equalizing the lubricant pressure with the ambient or borehole pressure. The pressure compensator is located in a lubricant reservoir that has a passage leading out of the bit adjacent the discharge nozzle. A flexible diaphram is located in the reservoir with its lip seated against the base of the reservoir. The lip protrudes outwardly and a protector member bears downwardly against the lip. A cap bears against the protector member compressing the lip. A retainer ring holds the cap with the lip under compression. A protective centering disc is attached to the center of the diaphram.

Abstract: A cutter with a replaceable cutting element is adapted to be mounted upon the rotary head of an earth boring machine or upon the body of an earth boring bit. The cutter is used in conjunction with an earth boring machine that functions to form a borehole or tunnel in the formation being bored. The cutter may operate to fracture rock between a proximate pair of kerfs in a manner to cause fragments of the formation to be separated from the formation being bored or may crush and disintegrate the formation. At least one annular cutting element is mounted on the periphery of the cutter body for contacting the formations. The cutter body includes an external annular threaded surface between the ends of the cutter body. The cutting element includes a threaded inner surface that mates with the threads on the cutter body. A locking shoulder on the cutter body is in contact with a locking shoulder on the cutting element.

Abstract: Each bucket includes a ground engaging leading portion characterized by roller cutter means alternating with scoop teeth transversely across the bucket. The scoop teeth on alternate buckets follow the path of roller cutter means on intermediate buckets. The scoop teeth on intermediate buckets follow the path of roller cutter means on alternate buckets.

Abstract: A rotatable cutter is mounted upon the bearing pin of a rotary rock bit. The cutter contacts and disintegrates earth formations during the drilling of an earth borehole thereby imposing a thrust load on the cutter. The thrust load consists of an out thrust load component substantially parallel to the axis of cutter rotation and a radial thrust load component substantially perpendicular to the axis of the cutter rotation. Substantially the entire out thrust load component is transmitted from the cutter through a ball bearing raceway on the interior surface of the cutter to the ball bearings and from the ball bearings to a ball bearing raceway on the bearing pin. The ball bearing raceways on the cutter and the bearing pin extend a substantial distance on either side of the axial axes of the ball bearings.

Abstract: The present invention provides a rotary rock bit with a heat pipe for conducting heat from the bit's bearings. The rotary rock bit includes a bit body with a connection for connecting the bit body to a rotary drill string. At least one arm extends from the bit body and a rotatable cutter is mounted on said arm. Bearing means are located between the rotatable cutter and the arm for promoting rotation of the cutter. A heat pipe is positioned in the bit body and the heat pipe extends into the arm. The heat pipe includes an evaporator section located near the bearings and a condenser section located near the external surface of the bit.