Abstract: An earth boring bit of the "air cooled" type that includes an air passage access system, including a generally vertical passage with an opening on the exterior of the leg or in the shank cavity that forms part of the body of the bit. This vertical passage is accessible through the opening by removal of a core that expands or retracts by altering the pressure exerted against it by two plates and a threaded fastener.

Abstract: A drill bit comprising a bit body detachably secured to a drill string having a chamber therein to receive drilling fluid at a first pressure from the drill string, a nozzle for exit of the drilling fluid to the space between the bit body and the well bore at a second pressure lower than the first, and a depending leg; a roller cutter; a bearing assembly for rotatably mounting the roller cutter on the leg; a lubrication system in the bit body comprising a reservoir of lubricant, passaging for flow of lubricant from the reservoir to the bearing assembly, a seal member for blocking flow of lubricant out of the bit, an expansible chamber for pressurizing the lubricant to a third pressure greater than the second but less than the first, and a biased diaphragm for pressure compensation secured in a recess in the bit body in fluid communication at one side thereof with the lubricant and at the other side thereof with the drilling fluid in the space between the bit body and the well bore; and a sensor for sensing a

Abstract: This invention discloses a method to protect the lubrication reservoir system for sealed bearing rotary cone rock bits. A multiplicity of flush-type tungsten carbide inserts are positioned in each leg of the rock bit surrounding the lubrication reservoir cover cap. The inserts prevent erosion of the leg around the cover cap, thus protecting the snap ring that secures the cover cap within the reservoir chamber.

Abstract: A bidirectional thrust bearing assembly is used between a downhole fluid motor and a rock bit for drilling oil wells. The bearing assembly has a stationary housing with radial journal bearing sleeves and a rotatable drive shaft also having radial bearing sleeves. A pair of oppositely facing thrust bearing rings are mounted in the housing. A second pair of thrust bearing rings are mounted on the shaft so as to have faces opposing the bearing faces on the first pair of rings. Belleville springs resiliently bias a pair of the thrust bearing rings apart and carry the thrust load between such rings. Each ring has a plurality of inserts of hard material, preferably polycrystalline diamond, at the bearing surface. Means are provided for circulating drilling fluid from the motor through the thrust bearing faces for forming hydrodynamic fluid bearing films in the bearing interfaces.

Abstract: A rotary drag drill bit is seen wherein cutter bodies are rotatively connected to a main body structure at a fully offset position. The fully offset position is defined by a rotational axis of each cutter body, a longitudinal axis of the drill bit and end support points or positions of the cutter bodies. The rotational axes of the cutter bodies are perpendicular to the longitudinal axis of the drill bit. The end supports of the cutter body are each equal distance from any point on the longitudinal axis of the drill bit. The cutter bodies of essentially ellipsoidal configuration, being slightly thicker at a mid-portion thereof. Cutting elements are connected to flutes projecting above an outer surface of each cutter body. In a primary rotational direction of the drill string and drill bit, the rows abrade the bottom and side walls of a well bore as the cutter body attacks the earth formation as the drill bit is rotated.

Abstract: A drill bit comprising a bit body detachably secured to a drill string having a chamber therein to receive drilling fluid at a first pressure from the drill string, a nozzle for exit of the drilling fluid to the space between the bit body and the well bore at a second pressure lower than the first, and a depending leg; a roller cutter; a bearing assembly for rotatably mounting the roller cutter on the leg; a lubrication system in the bit body comprising a reservoir of lubricant, passaging for flow of lubricant from the reservoir to the bearing assembly, a seal member for blocking flow of lubricant out of the bit, an expansible chamber for pressurizing the lubricant to a third pressure greater than the second but less than the first, and a biased diaphragm for pressure compensation secured in a recess in the bit body in fluid communication at one side thereof with the lubricant and at the other side thereof with the drilling fluid in the space between the bit body and the well bore; and a sensor for sensing a

Abstract: The present invention relates to an improved rotary drill bit having a bit body with at least one bearing pin attached thereto for rotatably carrying a roller cutter over a bearing system. The bearing system includes at least a forward bearing and a rear bearing with at least one inflow passage provided in the bit body for supplying fluid through the passage to the rear bearing during operation of the bit for flushing and for cooling of the rear bearing. The passage terminates in the bearing system ahead of a forward end of the rear bearing between an intermediate sealing arrangement and an annular outlet gap provided between the bit body and the roller cutter. The bearing pin includes a flange for axially fixing a forward end of the rear roller bearings with the inflow passage preferably terminating on the periphery of the flange. The sealing arrangement preferably engages a forward radial surface of the flange on the bearing pin.

Abstract: In order to prevent the moisture in the general air supply from entering the first flow and generating mud in the area of the cones of a drill bit assembly, separator means is provided within the plenum chamber supported on the housing walls proximate to the conduit through which a first flow path flows. This may be done by using a stand pipe supported on an orifice plate of the first conduit and extending above the openings of a second conduit. Perforations in the stand pipe are above the second conduit. A fluid flow diverter at the end of the stand pipe is preferably of conical shape, larger diameter than the stand pipe and arranged so that its edges extend below some of the perforations on the stand pipe so that air entering the first flow must reverse course to pass through the perforations. Water cannot readily reverse in this manner.

Abstract: A method and apparatus for providing a flow of lubricating fluid from a surface-mounted lubricating fluid source through a rotatable drill pipe to rotary cutting cones of a rotary drill bit for drilling in an underground formation, including pump means for providing a flow of lubricating fluid from the fluid source to an end of the drill pipe. Drill pipe conduit means extending along the length of the drill pipe is provided for receiving the flow of lubricating fluid and for directing the lubricating fluid flow along the drill pipe to the drill bit. Distribution conduit means at the drill bit extends from the drill pipe conduit means to the cutting cones and receives the flow of lubricating fluid from the drill pipe conduit means for directing the lubricating fluid flow to the cutting cones for lubrication thereof.

Abstract: Apparatus and methods are disclosed for drilling a well. A separator sub includes a cyclone separator which separates a stream of drilling mud into a less dense first portion and more dense second portion. The stream of drilling mud flows downward in an annular stream around the cyclone separator and then flows into a lower end of the cyclone separator. The less dense first portion of the stream of drilling mud is directed from the cyclone separator downward to a drill bit so that the drilling mud adjacent the drill bit has a density less than an initial density of the stream of drilling mud. The more dense second portion of the stream of drilling mud is directed upward from the cyclone separator and is ejected into a well annulus with an upward component of velocity and thereby reduces a hydrostatic drilling mud pressure adjacent the drill bit.

Abstract: A backflow control system for use in a gas circulation roller cone rock bit is disclosed wherein a single unit combination liquid-separator and positive action poppet check valve is used to restrict the entrance of water into roller cone bearings during drilling and to restrict the ingestion of detritus into the bearings and into the bit chamber during drilling interruptions. A quick-change mounting permits easy transfer of the valve unit form bit to bit.

Abstract: This invention relates to rotary rock drilling apparatus, particularly roller cone rock bits used with dry drilling of rock formations. Mining bits are typically air-driven, air-lubricated roller cone rock bits having open bearings, the air being driven through the bearing system between the roller cones and their associated journals. A lubrication system is disclosed which drips a lubricant in liquid form into the air passages communicating with each of the bearings associated with, for example, the three roller cones of the rock bit. Oil is entrained, along with the compressed air, and is directed to the bearings for cooling and lubrication purposes.

Abstract: An earth boring bit of the air cooled bearing type has features to improve cleaning of the borehole. The bit has three bit legs, each with a depending bearing pin that receives a rotatable cutter. Bearings are located between the bearing pin and the cutter. Passages communicate drilling fluid from the drill string to the bearings. A slot between the bit leg and the backface of the cutter enables air to be discharged from the bearing pin into the borehole. The portion of the slot on the lower side of the bearing pin is greater in cross-sectional flow area than the portion on the upper side. The portion of the slot on the lower side exposes the outer ends of the roller bearings to the borehole.

Abstract: A rolling cutter rock drilling bit is disclosed which features an internal lubricant pump utilizing an internal elastomeric member moving across a grooved rigid surface to circulate lubricant in the bit bearings as a result of the shear forces on the lubricant created when the elastomer moves across the grooves.

Abstract: A roller reamer assembly for mounting in a longitudinally extending undercut groove in a reamer body and having longitudinally slidable bearing blocks with cooperating locking members for securing the bearing blocks in the groove upon longitudinal movement of the bearing blocks to prevent undesired longitudinal and radial movement of the bearing blocks and an automatic lubricating system for the bearing blocks.

Abstract: An earth boring bit particularly for use in drilling mining blast holes, has features for reducing the possibility of cutter drag and reducing wear on the bit legs. The bit is of the type having three bit legs, a bearing pin depending from each bit leg, and a cutter with a central cavity mounted on each bearing pin with roller bearings. The roller race for the roller bearings is formed in the central cavity of the cutter. The lower side of each bearing pin commences at the outer side of each bit leg, eliminating the shirttail flange. Clearances are provided between the central cavity and the bearing pin at the backface for the discharge of air in a direction parallel with the bearing pin axis.

Abstract: A method and apparatus are disclosed for drilling a bore hole using a dual concentric drill pipe. Air is supplied through the outer pipe to the bit to cool the bit and jet cuttings upwardly in the bore hole to a suction inlet leading from the bore hole to the inner pipe. A negative pressure is applied to the inner pipe to bail the cuttings up the inner pipe. Makeup air flows down the annulus in the bore hole to the suction inlet and prevents upward movement of dust in the bore hole. A bore hole enlarging bit is disclosed and has expansible cutters which are expanded by hydraulic fluid pressure. In one form, the expansible cutters can also be retracted by hydraulic fluid pressure. The enlarging bit is employed to enlarge a pilot bore hole from a selected beginning location to the bottom of the pilot bore hole to form a blast chamber.

Abstract: A rotary bore hole enlarging bit is connected to a rotary pipe string having a drilling fluid flow path and an actuator flow path. The bit comprises a body structure including inner and outer telescopic body sections, expansible and retractible arms carrying cutters on the outer body section and an expander on the inner body section engageable with the arms to expand the arms and cutters upon telescopic movement of body sections in one relative direction. A piston and cylinder is provided between the inner and outer body sections to secure relative telescopic movement between the body sections. A first passage is disposed in the body structure and expansible arms and cutters for conducting drilling fluid to the cutters from the drilling fluid flow path, there being a second passage in the body structure for conducting actuator fluid to the piston and cylinder from the actuator fluid flow path.

Abstract: A multi-cone roller bit with a central pot member is disclosed, having releasably secured legs carrying rolling cutters mounted on the pot. The legs have an upper portion which can be releasably secured in a recessed central portion of the pot and an abutment region which contacts the pot. A tongue and groove arrangement holds the leg and pot from relative movement with one another, and a central tapered plug is reciprocably movable so as to clamp and unclamp the legs to the pot.

Abstract: A device for lubricating rotary drill bits of the type comprising a roller cutter (14) which is rotatably carried by means of a bearing system (15, 16, 17, 18). Fluid is supplied to the bearing system for cooling thereof through a cooling passage (31, 32, 33; 51, 61), and a lubricant is delivered to the cooling passage from a lubricant reservoir (36; 46) through a lubricating passage (40; 54). For purposes of controlling the supply of lubricant the outlet of the lubricating passage into the cooling passage is arranged axially behind the inlet of the lubricating passage in the lubricant reservoir.

Abstract: An improved lubrication and seal system for a rock bit that includes a bit body arranged to be connected to a drilling string or the like and having an axle portion thereon. A cutting member is journaled on the axle portion and provides a cavity between the axle portion and cutting member in which there are disposed a bearings for rotatably supporting the loads on the cutting member on the axle portion. A pressurized fluid passageway extends through the bit body to the cavity for transmitting bearing conditioning fluid to the bearings. A permeable material having a lubricant in the pores in the material is disposed in the available space between bearings in the cavity in contact with the load carrying bearing and in the fluid passageway whereby the lubricant in the pores is gradually deposited on the bearing to provide a generally continuous in situ lubrication thereof.

Abstract: A rotary drill bit comprising at least one rotatably carried roller cutter (17) and provided with passages (26,27,28) for supplying cooling fluid to the bearing system (11-15) of the roller cutter. For purposes of preventing the heat generated at an annular surface (31) transmitting axial forces from causing rapid bearing wear a recess (32) is provided in the annular surface (31). The recess (32) communicates with the passages (26,27,28) and extends entirely around the bearing shaft (16) for allowing circulation of cooling fluid therearound.

Abstract: A rock bit used for drilling with air as the circulating fluid, and a centrifugal separator to filter liquid and other contaminants from the air diverted to the bit bearings. The filter generates a fluid vortex with radial vanes, each having plural pitches, located within the shank of the bit. Bearing coolant passages, located beneath the separator, receive filtered air from a central, filtered air location. The vortex centrifugally forces the water and other contaminants outwardly into nozzle passages that direct fluid toward the bottom of the borehole.

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: An unsealed rotary drill of the type comprising a bearing shaft, a roller rotatably mounted on the shaft, cutting inserts carried by the roller, bearing for rotatably supporting the roller on the shaft, and a flushing channel terminating at an end surface of the bearing shaft for conducting cooling air to the bearing. The bearing includes an axial bearing comprising an insert plate formed of sintered hard metal alloy, and a supporting plate formed of a material which is less hard and less wear resistant than the metal alloy. The supporting plate contains a solid lubricant. The supporting plate and the insert plate present opposed bearing surfaces. The insert plate is mounted in the end surface of the bearing shaft such that a rear surface of the insert plate is acted upon by cooling air from the flushing channel.

Abstract: In a drilling bit, a cone shaped cutter is rotatably mounted on a spindle on anti-friction bearings and on a friction bearing in the nose of the spindle. A passage is formed in the exterior cylindrical surface of the spindle nose in the load bearing zone. This passage is connected to a radial passage on the end or thrust bearing surface of the spindle, and the center of the thrust bearing surface communicates with a weep hole in the nose of the cutter. Cooling fluid is ducted through the spindle and through these passages to provide cooling directly in the area where the generated heat is the greatest and fluid flow a minimum in previous constructions.

Abstract: Method and apparatus are disclosed for drilling a pilot hole and subsequently enlarging the pilot hole in earth formation. A dual concentric pipe string is used for circulating air downwardly through the outer pipe, through a pilot bit and upwardly through the bore hole outside the pipe string to bail cuttings, during drilling of the pilot hole. The air pressure expands the cutters of an expansible bit while a limited portion of the air supplied cools the cutters. After the cutters are fully expanded, additional air is utilized to clean and cool the cutters. Air is returned through the inner pipe of the dual concentric pipe string. A venturi device is utilized to induce return flow through the inner pipe during enlargement of the hole and to vacuum residue when enlargement is completed. The dual concentric pipe string is made up of lengths of pipe providing threaded, sealed joints.

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 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 and materials 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 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: 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 system for continuous lubrication of bearings in a drilling apparatus including a roller bit having at least one pivot and a cutting roller rotatably supported on the pivot by bearings. The system comprises pumping means in the form of spiral or oblique grooves on one of the spaced confronting faces of the roller bit and cutting roller and a flow opening or port arranged to effect flow of a flushing liquid through the bearing upon rotations of the cutting roller. The grooves may be selectively oriented to pump flushing liquid through the annular gap between the roller bit and cutting roller faces radially inwardly or radially outwardly for a given direction of rotation of the cutting roller.

Abstract: A system for lubricating bearings in a drilling apparatus including a roller bit with at least one pivot and a cutting roller rotatably supported on the pivot by bearings. A cavity or chamber is formed in the roller bit for a non-compressible flushing liquid. The flow channel which communicates with the chamber at one end and the bearing cavity at the other end, provides a flow path for the flushing liquid to the bearing cavity. In one form the flushing liquid discharges to the bearing cavity at a point remote from an annular gap between the outer axial end face of the cutting roller and the roller bit. In another embodiment circumferentially spaced discharge ports are located between the bearings so that a portion of the flushing liquid is discharged to the environment and the remainder flows through the bearings and out the annular 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 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 rotary rock bit with passageways for conducting air or other gaseous fluid to cool the bearings and flush cuttings from the borehole includes valve means for controlling the entry of water into the bearings. The stream of air or other gaseous fluid is directed through a valve system that prevents water from reaching the bearings. In one embodiment a truly positive backflow shutoff valving arrangement through both the nozzle and bearing passageways provides a means for more effectively preventing water and cuttings from entering the bearings and bearing passageways of the bit.

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 rotary drill bit is provided with confronting large hard annular bearing surfaces on the journal-bearing body and on the journal-mounted conical cutter of the bit. The hard surfaces are generally normal to the axis of rotation of the cutter to bear axial loads, and provide a large bearing area resulting in relatively low unit pressures on the bearing surface. The hardness of the bearing surfaces should be greater than the hardness of the rock or other material being drilled. The journal and cutter may have confronting but spaced inner hard bearing surfaces which come into sliding, bearing contact with each other as the first-mentioned bearing surfaces are worn down. Cooling means are provided to cool the bearing surfaces, and an internal ball bearing and race assembly permits limited movement of the cutter axially on the journal to allow for wear of the bearing surfaces and to eventually bear axial loads. Also described is a nozzle means for sweeping cuttings to the periphery of the drill hole.

Abstract: A sealing arrangement for a rolling cutter designed to protect the antifriction bearings disposed between a support shaft and a rotatable outer body of the rolling cutter. A sealing arrangement is provided comprising at least two seal means located outward from the antifriction bearing of a rolling cutter and further comprising a cavity means between the two seal means so that flushing coolant, fluid or grease may be injected into the sealing arrangement and, when injected, will carry heat, dirt and other contaminants outward and away from the interior of a rolling cutter thereby preventing damage to the antifriction bearings and the seal means located nearest to the antifriction bearings.

Abstract: A bearing assembly for a rotary drilling tool for a continuous mining machine includes inner and outer races having respective annular bearing surfaces and an annular channel formed between the races for water lubrication and cooling of roller bearing members positioned within the channel. A pump supplies pressurized flow through the channel sufficient to lubricate the bearing and to prevent feedback of rock particles. A transfer passageway drains the water from the bearing assembly and feeds it to the tool to cool the cutter teeth and to allay the fine respirable dust which is potential health hazard to the mine workers. The rollers of the bearing each include an annular notch to form a portion of the flow channel. The notches occupy approximately fifteen percent of the cross-sectional area. Elastic ring support for the outer race absorbs a major portion of the drilling stress from the tool. Rotary water seals and wipers beside the bearings form a rotary water-tight joint.

Abstract: A liner hanger assembly and method of installation for use in oil and gas well operations having multiple individual hanger units arranged in series for even load distribution. Each individual hanger unit carries a proportional amount of the weight load of a suspended well pipe (casing liner) and has a balanced pressure, sealed bearing which facilitates rotation of the casing liner in the well bore during cementing operations.

Abstract: A drill bit construction of the rotary cutter type in which cutter journals extend downwardly from the bit body and toward each other at an angle, the provision of bearing sleeves removably mounted on the journals and rotary cutters removably and rotatably mounted on the bearing sleeves, permitting the replacement of the bearing sleeves or the customary roller or ballbearings and also permitting replacement of the rotary cutter itself if the latter has become worn or damaged.

Abstract: A sealing system for a rotary rock bit acts as a barrier to the pulverized cuttings and other materials in the borehole and prevents the materials from entering the bearing area through the cone mouth opening of the cone cutter. The bearing rollers are substantially captured in a groove machined into the cone cutter. This allows a seal unit to be located at a substantial distance from the hostile drilling environment and increases seal life. The shirttail portion of the bit body and the base of the cone cutter cooperate to retard materials in the borehole from contacting the seal unit. The sealing system is provided without reducing the bearing capacity of the bit's bearing system.

Abstract: Cone shell erosion between inserts is substantially reduced by positioning small, flat-topped compacts in the vulnerable cutter shell areas. At least one row of substantially outwardly projecting formation contacting inserts are located on the rock cutter. A row of substantially flush compacts are embedded in the cutter shell alternately positioned between the outwardly projecting formation contacting inserts.

Abstract: In boring apparatus of the type having cutters mounted for rotation about respective cutter axes in a frame which is in turn rotatable about a frame axis, each cutter having a body carrying teeth which in operation sweep a surface which is oblique to the axis of advance of the apparatus, that improvement wherein each cutter has selected tooth regions, preferably of alternating high and low tooth densities, spaced along the respective cutter axis, the tooth regions of the cutters are arranged in an ordered cycle progressing along the frame axis, and regions adjacent each other in the cycle are on different cutters and overlap each other along the frame axis.

Abstract: This invention relates to flow restrictors in fluid motors where the operating fluid also passes through the bearings of the motor.