Abstract: Improved back reamers (20, 60, 80, 100) are disclosed for use in back reaming a pilot bore in a trenchless boring operation. In three of the heads (20, 60, 100), truncated cylinders are mounted on a body (22) of the head with the truncated cylinders each defining a convex truncated surface facing the walls of the bore. Rotation of the head while moving the head in the direction to be reamed, the convex truncated surface will compact the soil into a wall of the bore of desired final diameter and stabilize the wall. A back reamer (80) is provided with a plurality of directional cams (84) which permit the head to be oscillated in either direction about the drill string axis. The heads can be reversed to act as drill bits as well.

Abstract: An under-reaming tool for use in preferably horizontal and extended reach bore holes includes a succession of stabilizers, under-reamers and expandable stabilizers. A common drilling mud activator is provided for the expandable elements of under-reamers and expandable stabilizers. A preferred under-reaming device comprises a main body with a number of guiding surfaces distributed over the circumference thereof which have a pitch increasing radially in an axial direction and with a ring collar formed as a piston in a surrounding cylinder housing having a small and a large radial annular surface, and having reaming pads/wings and/or stabilizer pads/wings in sliding contact with a respective guiding surface, the pads being taken up in ports in a jacket surrounding the main body, in such a way that the pads can only be moved radially relative to the jacket, the jacket being attached to or formed as a part of the cylinder housing.

Abstract: A large shaft over-reamer apparatus and method using a driver means and a detachable reamer cutter means. The driver means may include a work platform for personnel to work on. The driver means is positioned in a drilled pilot hole for stability and vertical control. The top of the driver means is attached to a kelly bar that transmits rotational force to the driver. The driver means has lug pins to releasably connect the driver means to the reamer cutter means. Releasably connecting the driver means to the reamer cutter means allows the reamer cutter means to be left inside the shaft or hole while the kelly bar lifts out excavated material in a bucket attached to the driver means. The reamer cutter has radial cutters and wiper blades. The wiper blades help funnel the excavated materials to a bucket.

Abstract: Improved back reamers (20, 60, 80, 100) are disclosed for use in back reaming a pilot bore in a trenchless boring operation. In three of the heads (20, 60, 100), truncated cylinders are mounted on a body (22) of the head with the truncated cylinders each defining a convex truncated surface facing the walls of the bore. Rotation of the head while moving the head in the direction to be reamed, the convex truncated surface will compact the soil into a wall of the bore of desired final diameter and stabilize the wall. A back reamer (80) is provided with a plurality of directional cams (84) which permit the head to be oscillated in either direction about the drill string axis. The heads can be reversed to act as drill bits as well.

Abstract: A tool for milling a down-hole casing or tubing comprising a tubular body rotatable about its longitudinal axis and having a longitudinal passage therethrough. Means is provided at a first end of the cylindrical body for connection to a drive means to rotate the body. The first end forms the upper end of the body in the working position. At least one first blade extends outwardly from the cylindrical body and has a lowermost cutting edge extending upwardly from its innermost portion at an angle of from about 2.degree. to about 60.degree. to a radial plane perpendicular to said longitudinal axis, and at least one second blade extends outwardly from the cylindrical body and has a lowermost cutting edge extending downwardly from its outermost portion at an angle of from about 2.degree. to about 60.degree. to a radial plane perpendicular to said longitudinal axis.

Abstract: New apparatii and processes are disclosed to create fluid continuity between opposite ends of a route drilled or bored under and/or around an obstacle. This invention allows fluids to be pumped through a reamer and a hollow swivel from either or both sides of the obstacle. It also allows the direct transfer of fluids from one side to the other through the connecting conduit located in the annular space produced during drilling and reaming operations.

Abstract: A milled tooth rotary cone rock bit, as it is operated in a borehole, subjects the heel of each cone into contact with the borehole wall when the gage row milled teeth wear. The heel row of each cone is relieved and tungsten carbide chisel inserts are equidistantly placed within the relieved heel row. The heel row inserts cooperate with the gage row milled teeth and progressively cut more of the gage of the borehole as the row of milled teeth on the gage of the cone wear. Moreover, the gage row milled teeth are partially hardfaced leaving relieved areas on the cutting side of each tooth to enhance the cutting action of the gage row of each cone.

Abstract: A milling tool (3-5; 51-53) in combination with a stabilizer therefor has a milling tool with a body (51) with a plurality of radially extending and circumferential blades (3) diposed about the body. The lower portion of the body (51) has a portion (57) upon which is located a stabilizer (70), the stabilizer comprising a sleeve (71) about which are disposed a plurality of helically disposed fins (75). The sleeve (71) has an internal screw thread (73) for mating with an external screw thread (55) on the body (51).By providing a single milling tool on site and a plurality of separate pilot stabilizers so stabilizer sleeves can be quickly and easily secured to the milling tool thereby eliminating the necessity of cutting the fins to the required radial height when on site.

Abstract: An underreamer tool has a generally cylindrical body with a threaded top end for connection to a tubing string, a threaded lower portion to receive a drill bit, and a longitudinal fluid passageway extending centrally through the body. The body has three flat surfaces formed on its exterior in circumferentially spaced relation to define a generally triangular cross section intermediate the top and bottom ends of the body. A cutter blade is pivotally mounted on each of the flat surfaces. A piston is slidably received in a bore in the upper portion of the body and has central fluid passageway therethrough. Push rod members are connected to the piston inside the body and each has an exterior portion slidably mounted in a slot on the exterior of the body engaging the cutter blades for moving them between a retracted position against the body and an extended position outward therefrom.

Abstract: A pilot casing mill for removing unwanted pipe from a well bore, which includes a cylindrical pilot having helical vanes and adapted for mounting on one end of a cylindrical mill body. The mill body is provided with longitudinal slots which receive outwardly-extending blades fitted with multiple cutting elements for engaging and cutting the pipe when the pilot casing mill is mounted on the end of a rotatable drill string and inserted in the well. In a preferred embodiment of the invention the blades are removably secured in the slots by removable wedge blocks and may be longitudinally adjusted in place to align adjacent rows of cutting elements, by operation of multiple adjusting screws seated against an adjusting screw ring mounted in a circumferential slot provided in the mill body.

Abstract: A milling apparatus is disclosed. The structure includes first and second upper subs threading together and having an inner axial passage. A long stinger fits in this passage and connects with a mandrel which is telescoped within an outer tubular body for a vertical or telescoping movement. The mandrel is formed with lengthwise slots, enabling independent knives to be positioned in each of the slots. The knives are engaged for controlled radial deflection by a dovetail connection, and the slots terminate at a sloping shoulder to force the individual cutters radially outwardly. An expansion chamber below the mandrel forces the mandrel upwardly with respect to the surrounding outer tubular body, causing the cutters to extend through individual lengthwise slots in the outer tubular body to the cutting position.

Abstract: An apparatus for milling away tubular conduits encased within well bores is disclosed. The milling device consists of a cylindrical body. The body forms longitudinal slots therein for radially disposed replaceable cutter blades that are inserted through the slots from the inside of the body. A central mandrel mechanically locks the replaceable blades between the mandrel and the tubular body. A finned pilot head or guide is affixed to the downstream end of the milling apparatus, the opposite threaded upstream end is adapted to be connected to a drill string.

Abstract: A drill bit for producing an undercut. The drill bit includes a shaft and a cutting edge that is disposed asymmetrically radially beyond the shaft in a front end portion of the drill bit. A planar guide surface is provided on a conical end face of the drill bit. This guide surface is disposed radially opposite the cutting edge. The guide surface terminates at a concentric tip of the drill bit.

Abstract: An apparatus and method for drilling and then installing a production conduit (46) within an enlarged bore hole (D) along an underground path (P) between two surface locations (C, D). Upon completion of a pilot bore hole (B), a reamer (48) enlarges the bore hold (B). The drill string (10) is returned to the exit opening (E) for connection to the production conduit (46) for pulling the conduit (46) within the enlarged opening (D). One embodiment (FIGS. 19-21) utilizes canted rollers (168) for supporting the production conduit (46) at the exit opening (E) and effecting rotation thereof as the production conduit (46) is fed into the enlarged diameter opening (D).

Abstract: A drilling tool for use in drilling operations for providing shock absorption capability and lateral support to the rotary drill string. The telescoping axial load shock absorber is positioned immediately adjacent at least one lateral support provided by a reamer or stabilizer. The stabilizer preferably employs a removable fixed blade secured to the tool by an undercut groove. The roller cutter for a reamer is also mounted in a preferred unique manner with the mounting blocks secured in a recess having an undercut retainer portion in the event of bolting failure. The mounting's brackets may be formed integral of the tool body or attached by welding or the like. A preferred form of mounting a blade on a stabilizer tool is also disclosed.

Abstract: A drilling tool for use in drilling operations for providing shock absorption capability and lateral support to the rotary drill string. The telescoping axial load shock absorber is positioned immediately adjacent at least one lateral support provided by a reamer or stabilizer. The stabilizer preferably employs a removable fixed blade secured to the tool by an undercut groove. The roller cutter for a reamer is also mounted in a preferred unique manner with the mounting blocks secured in a recess having an undercut retainer portion in the event of bolting failure. The mounting's brackets may be formed integral of the tool body or attached by welding or the like. A preferred form of mounting a blade on a stabilizer tool is also disclosed.

Abstract: An apparatus for creating annular cavities in the bottom of drilled holes in any medium having a body, an axle within the body at one end and rotated by a conventional drill, a reamer secured to the axle at its other end, an inner part enveloping the axle and an outer part enveloping the inner part, both parts being eccentric and rotatable with respect to each other. Their respective eccentricities are such that when opposing each other in opposite directions, the axle is parallel to the outer part. Joint rotation of the parts causes the reamer to move in a planetary manner. The outer part may be held stationary or dragged along by the inner part for joint rotation. Channels are provided within the parts to the reamer to supply cooling water to the reamer and to remove waste material generated by the reamer.

Abstract: A hole opener for placement in a drill string having a body generally comprising a collar, a triangular mid-section, a triangular shaped pilot and a bull nose. The collar provides means for attaching the tool body to the drill string. The triangular mid-section has three longitudinal, radially spaced apart blade members that are parallel to the central axis of the tool body so that the blades can cut into the walls of the bore hole to enlarge the size of the bore hole. Three annular flow zones span the distance between the blade members so that fluids and cuttings can circulate through the bore hole. The pilot section also has three longitudinal, radially spaced apart blade members that are parallel to the central axis of the tool body bore and three annular flow zones which span the distance between the blade members of the pilot. The pilot section is downhole from the mid-section.

Abstract: A well bore enlarger comprising, in its fixed-arm embodiment, a tubular housing member having an enlarged section with an outer diameter substantially the same as the well bore diameter, the enlarged section having a plurality of longitudinal cut-out portions defining blades of the enlarged section therebetween; a longitudinal slot within the blade; a cutting arm mounted to the blade within the slot having cutting edges and a fluid gallery between the cutting edges which gallery communicates with the slot and the well bore; synthetic diamond material attached to the cutting arm; and means on the tubular housing member for directing a fluid through the fluid gallery of the cutting arm. In the expandable-arm embodiment of the well bore enlarger, the tubular housing member is formed with the enlarged section as previously described, with slots, blades and cut-out portions.

Abstract: A borehole conditioning tool suitable for use in a drill string, the tool including a tubular body portion having a plurality of elongated, circumferentially spaced retainer slots for housing wall contacting members, each retainer slot being defined by a pair of opposed elongated slot side walls and a plurality of wall contacting members in the form of elongated stabilizer blades which are mounted in the retainer slots, each stabilizer blade having a pair of opposed blade side walls. In the borehole conditioning tool the slot side walls and blade side walls are shaped so that for each stabilizer blade one blade side wall is in engagement with one slot side wall, while the opposed blade side wall is in engagement with the opposed slot side wall along only a portion of the length of the blade side wall in at least one interference zone, the degree of interference being sufficient to locate the blade in position in the slot.

Abstract: A downhole tool for insertion in a drill stem includes elongated cylindrical half sleeve tool sections adapted to be non-rotatably supported on an elongated cylindrical body. The tool sections are mountable on and removable from the body without disconnecting either end of the tool from a drill stem. The half sleeve tool sections are provided with tapered axially extending flanges on their opposite ends which fit in corresponding tapered recesses formed on the tool body and the tool sections are retained on the body by a locknut threadedly engaged with the body and engageable with an axially movable retaining collar. The tool sections may be drivably engaged with axial keys formed on the body or the tool sections may be formed with flat surfaces on the sleeve inner sides cooperable with complementary flat surfaces formed on a reduced diameter portion of the body around which the tool sections are mounted.

Abstract: A roller reamer/stabilizer tool is shown with rolling cutter assemblies removeably retained within elongated pockets in the body of the tool by cap members capturing opposing ends of the cutter axle pin. The cap members are received in sockets adjacent opposed ends of the pockets and secured thereon by balls, received within a passage defined by the mating faces of the socket and caps, and by threaded bolts. A countersunk bore in the cap members receives the bolts therethrough and provides an entry into a transverse opening through the cap to the passage for inserting or removing the balls. A shim plate between the cap and the body determine the gauge diameter of the tool.

Abstract: Drilling equipment for steering relatively long boreholes in rock strata comprises an adaptor for installation adjacent to the drill bit, the adaptor having an inner rotary component drivably connected between the drill rod assembly and the drill bit and a relatively outer component. Releasable latch means are provided having two operational modes in the first of which the inner and outer components are fixedly engaged for rotary motion and in the second mode of which the inner component can rotate relative to the outer component. Also actuatable means are provided for controlling the operational mode of the releasable latch means.

Abstract: A mining drill mountable in a holder of a drilling machine. The drill includes an elongated shaft having an internal bore extending longitudinally therethrough. A cutting bit is mountable on one end of the shaft and includes a cutting tip mounted at one end thereof and a plurality of cutting teeth disposed about its periphery. A partial longitudinal bore is formed in the cutting bit and is alignable with the bore in the shaft. An aperture is formed in the cutting bit in communication with the bore in the cutting bit to direct debris through the aperture into the aligned bores in the cutting bit and shaft. A collar is mounted on the shaft and has a downward-extending inclined top surface. At least one aperture is formed in the shaft adjacent to the collar in communication with the interior bore in the shaft to direct debris into the bore. A cutting edge is formed on the bottom of the collar.

Abstract: This invention relates to large diameter raise bore rock bits. The invention comprises a means in which extensions may be attached to the outer diameter of the body of the rock bit, thus providing a variable diameter raise bore rock bit. The extensions are mounted to the primary body of the bit such that compressive loads are imposed on the attachment means. These compressive loads are transmitted from the extensions of the body by designing the extension portions of the bit such that they interlock to the basic bit body. The mating surfaces of the attachment means transmit predominantly compressive loads acting substantially normal to the load bearing surfaces. The attachment means are further designed to increase the grip of the extended bit portions as increased loads are applied to the body of the rock bit.

Abstract: A reamer apparatus is adapted for use in combination with a radial whipstock assembly in drilling a curved bore in a subsurface formation at a predetermined angle of build. The reamer apparatus is comprised of a drill bit, at least one articulated joint or drill collar connected to the lower end of the drill string, and a stabilized reamer interconnected for rotation behind the drill bit which includes cutter blades overgauged in relation to the drill bit and projecting substantially in outward radial directions from the reamer body, each blade having an elongated cutting edge which extends substantially parallel to the direction of drilling and a stabilized leading end so as to stabilize the reamer and avoid preferential cutting as the drill bit proceeds along the desired course.

Abstract: A mill or crusher useful for crushing and grinding material employing mechanical vibratory drive force at a sonic frequency. A drive shaft having orbiting eccentric weight means fixedly attached thereto and having freedom of motion both rotationally and laterally is rotatably driven by a drive motor to generate quadrature related vibratory force components in the drive shaft. Rotatably supported on the drive shaft by means of suitable bearings is a driving member having mass (inductive) inertia in said sonic frequency range. A "slave" member is freely supported on vibration isolation members in external concentricity with the driving member so that it is effectively in a "floating" condition, thus presenting a mass reactance in said sonic frequency range. Material to be milled or crushed is fed in the gap between the driving member and the free-floating "slave". Cycloidal force is delivered from the shaft to the driving member to precess or roll around on the inside wall of the free floating slave member.

Abstract: A method is disclosed of smoothing out a curved section of a well bore that has been drilled with a bent sub-downhole motor assembly. The method includes moving a reamer with a body having a cylindrical section and a lower tapered section equipped with a plurality of cylindrical cutters on each section through the curved section, while being rotated by the drilling assembly to be used to continue drilling the well bore below the curved section.

Abstract: An underreamer utilizes a plurality of cutting arms each having a plurality of tungsten carbide inserts, some of which have synthetic diamond cutting surfaces. There is a synthetic diamond gage cutter at the outer end of each cutting arm, and at least one other synthetic diamond cutter located more inwardly on the arm. The gage cutter is offset a greater distance from the leading side of the arm than are such other cutters. Recessed regions in front of the synthetic diamond cutters expose their full cutting faces while leaving steel for support of the cutters. Tungsten carbide inserts on the ends of the cutting arms between the leading side and the gage cutter minimize erosion of the steel arm and help prevent the gage cutter from being dislodged. The underreamer includes a hydraulic plunger for activating the cutting arms from a fully retracted to a fully deployed position, and a nozzle which ejects fluid toward the arm cutting surfaces during deployment and operation of the cutting arms.

Abstract: A drill string stabilizer in which the wall-contacting wear elements are secured in their accommodating slots by an undercut along each side and a tapered wedge-receiving notch along the underneath side for accepting one or more wedge pieces. In one embodiment, the tapered notch is along the side of an axially elongate slot and a plurality of wedges are located in securing position along one side. In another embodiment, there are tapered notches along the center between two separated sections of wear elements. In a third embodiment, the slot for the wear elements is not axially elongated but on a spiral angle. In a fourth embodiment, a pluraity of short wear elements are employed end-to-end, each with its own wedge piece and each also located on a thrust-bearing and locating pin.

Abstract: A reamer for removing paraffin, scale, ice and other accumulations from the inside surfaces of oil well pump tubing and casing which includes a hollow, tapered shell or housing fitted with external blades and having an enlarged upper internal bore area to accommodate a threaded lock nut, and a threaded shaft projecting into the housing cavity in threadable cooperation with the lock nut and provided with stops to permit limited rotation of the shell on the shaft and to prevent the shaft from exiting the shell when fully extended from the shell on the lock nut. When the reamer is lowered by means of a wire line and swivel joint into a length of tubing or casing to the constricted area, and the shaft is extended in the shell, a repetitive impact load on the projecting end of the shaft effects rotation of the shell and blades on the shaft to remove the deposits.

Abstract: A keyseat wiper or reamer for enlarging keyseats which are often formed in drilling bores during well drilling operations. The wiper comprises a generally cylindrical body including a cylindrical middle guard portion which has a greater cross-sectional diameter than the greatest diameter of the cutting elements of the tool, the middle portion being free of any cutting elements. Cutting elements extend in a tapered manner from the middle portion to opposed locations toward the ends of the wiper. Because the middle guard portion does not carry cutting elements and is the largest diameter portion of the keyseat wiper, the keyseat wiper will cut only when the hole through which it is passing is of diameter smaller than that of the middle guard portion or when the well bore has a curve or dogleg.

Abstract: An improved broach is disclosed incorporating, in the preferred and illustrated embodiment, an elongate tubular member constructed in the fashion of a drill collar having a raised external thread cut thereon in helical fashion, the thread having a top face. The thread tapers from the bottom to a maximum diameter at a very gradual rate. The top face includes a generally flat, exposed surface which is reinforced with particulate tungsten carbide. It additionally includes inserts of tungsten carbide at periodic locations as, for example, inserts located at ninety-degree intervals along the thread face. The inserts extend relatively deep and are constructed of a solid block of tungsten carbide in a supportive alloy. Another form has inserts made of cylindrical pellets.

Abstract: For use in a drilling string, the preferred and illustrated embodiment depicts a drill collar to be placed in the lower parts of the drill string for straightening the hole. The preferred embodiment utilizes a generally square drill collar with a thick or heavy wall. It is square in cross section along the greater portion of its length, the four corners being slightly rounded to a specified diameter on rotation, and the four lengthwise corners of the regular cross section are all reinforced with hardfacing material to a specified depth, typically tungsten carbide. The four edges abrade the bore hole as the drill string penetrates the earth. In addition, the lower end of the tubular body includes lengthwise flutes in the form known on a stabilizer to guide the hole straightening device into the hole to be reamed by operation of the device.

Abstract: A stabilizer for use in conjunction with a rotating drill string of a rotary drilling rig. The cutting blades of the stabilizer are received in close tolerance relationship within a longitudinally extending slot formed in a main body portion of the stabilizer. The slot outwardly opens and includes opposed sidewalls and opposed ends. The blades have opposed sidewalls and opposed ends and are made complementary respective to the geometrical configuration of the slot. A groove is formed in each sidewall of the slot and in each sidewall of the cutting blade such that when the blade is positioned within the slot, the grooves jointly form spaced cylindrical passageways. A plurality of holding balls fill the passageways and are removably captured therewithin, thereby releaseably securing the blade to the stabilizer body with great force so that the blade cannot inadvertently become lost downhole in a borehole.

Abstract: The eccentric journals of a tandem roller stabilizer are azimuthally positioned relative to each other by cylindrical pins removably disposed in cylindrical holes extending off-axially parallel to the stabilizer axis, the holes being formed by semi-circular cross-section grooves in the outer periphery of the mandrel and correlative semi-circular cross-section grooves in the inner peripheries of the journals.

Abstract: The eccentric journals of a tandem roller stabilizer are azimuthally positioned relative to each other by multiple lead threads on the mandrel onto which the journals of the successive roller assemblies are screwed, the journal of each roller assembly having like multiple lead thread of an integral number of turns per lead. In assembling the successive journals on the mandrel each journal is started on the lead immediately adjacent to the lead on which the preceding journal was assembled, progressing continuously in the same direction around the mandrel, whereby each journal is displaced azimuthally from adjacent rollers by an angle x equal to 360/n.degree. where n is the thread multiplicity and is equal to the number of roller assemblies on the stabilizer.

Abstract: The apparatus comprises means for coupling to a standard raise boring head for extending the radius of the head. The apparatus comprises a support which is bolted or welded to a terminal end of the raise boring stem and to the underlying surface of the principal cutter bracket mounting platform of the head, and the support has means for selectively coupling thereto cutter mounting extension elements each of which comprise ancillary cutter bracket mounting platforms.

Abstract: A frusto-conical multi-stage reamer constructed from a sequence of reamer stages is disclosed. Each reamer stage includes a central stem having a coupling at the leading end and a coupling at the trailing end. A plurality of circumferential arms extend from the central stem of each reamer stage and are inclined in a common direction with respect to the axis of the stems. The free ends of the arms are directed outwardly and forwardly with respect to the stem, and individual reamer teeth are attached to the free end of each arm. The radial extent of the arms of each stage of the sequence is a preselected increment greater than the radial extent of the arms of each preceding stage. In operation, the reamer stages are connected in sequence by the aforesaid couplings and simultaneously rotated and pulled through a pilot hole to produce an enlarged aperture.