Abstract: A boring tool is provided with first and second rectangular reversing cut plates which have, in each case, two short and two considerably longer cutting edges. One of the reversing cut plates is arranged connecting to or intersecting the axis of rotation of the boring tool, while the other reversing cut plate 12 is arranged connecting to the outer circle defined by the boring tool. The cutting edges active in each case on the face side of the boring tool have a straight construction and they overlap to a greater or lesser extend, in accordance with the bore diameter. The bend-free and jog-free construction of the active cutting edges of the cut plates makes possible the use of the same reversing cut plates on boring tools having different diameters with only the extent of the overlap of the cut plates being changed.

Abstract: A drilling tool, in particular a rock drill, is proposed, which is formed from a drill head, a clamping shank and a helical shank which is located between them. In order to produce a cost-effective drilling tool, the initial material used is a polygonal profile which is provided with a conveying helix groove in the region of the helical shank.

Abstract: A system for drilling a horizontal bore through frangible material includes a barrel mechanism containing a automatically reciprocating piston mechanism for automatically delivering hammering blows to a bit for chipping away the frangible material, a fluid distributor for directing fluid to and exhausting pressurized fluid from the piston mechanism without exposing the wall of the bore being created to fluid pressure greater than ambient atmospheric pressure, a spline/flute arrangement for causing the bit to rotate with the barrel mechanism, a motor and swivel mounted on a driven platform mounted on a supporting frame for urging the bit against the frangible material and for supplying the pressurized fluid, a pushing mechanism for non-rotatingly and simultaneously installing casing joints as various components of the system is rotatingly drilling the bore, an augering arrangement for, in conjunction with the casing joints, removing the drilling debris, and drill/auger stem sections for extending the drilling

Abstract: A rock drill has an axially extending drill shaft (2) with at least one helically shaped drilled material removal groove (3) and a drillhead (5) formed of a hard metal alloy. The drillhead (5) is secured to an end face of the drill shaft (2) such as by welding or soldering and has a main cutter (6) extending along a diagonal of the drillhead and at least one supplementary cutter (7, 8) extending along another diagonal of the drillhead. The supplementary cutter (7, 8) projects axially outwardly from a radially outer section of the main cutter (6).

Abstract: An earth auger has a center shaft and a helical flighting extending along the axis of the shaft. The flighting and the center shaft have opposite ends that are identical in construction, so that the auger can be driven from either end by a power unit.

Abstract: A drilling and/or chiseling tool is formed basically by a shaping without cutting procedure and has a axially extending shaft (1) with at least three helical drilled material removal grooves (2). The shaft (1) has a shank (3) at its trailing end in the drilling direction, and at the opposite end, leading in the drilling direction is a drilling head (6). The drilling head (6) has a recess for holding a hard metal insert (8). Because of the number of removal grooves (2), the course of the grooves is approximately parallel to the shaft axis, whereby in the drilling head (6) region there is adequate material for laterally supporting the hard metal insert (8). Accordingly, an expensive correction of the shape of the removal grooves (2) in the region of the drilling head (6) can be avoided.

Abstract: An earth displacement drill is provided including a drill tube which can be driven for rotary movement and a boring tip connected thereto, wherein the boring tip has a cylindrical part which adjoins the drill tube and has at least two helical strips uniformly distributed around the circumference, which climb upwardly at a shallow angle, with the flat side of the strips preferably extending substantially parallel to the radius at the relevant position and in particular only over a fraction of the circumference of the cylindrical part. The boring tip also has a tapering part located beneath the cylindrical part and having at least two arched surfaces which are uniformly distributed around the tapering part. These arched surfaces expediently extend approximately parallel to the vertical and preferably more steeply than the helical strips.

Abstract: A drilling tool has a shank (1) at one end, a shaft (2) with two helical grooves (5, 6) and the shaft (2) extends from the shank to the other end of the drilling tool. A drill head (8), with a cutting plate (7) inserted in it, is located at the opposite end of the shaft (2) from the shank (1). The cutting plate (7) has a cutting tip (74) projecting axially outwardly from the drill head (8). The cutting plate has a dimension (B) extending perpendicularly to the axis of the drilling tool and the dimension (B) is greater than the diameter of the drill head (8). On the opposite sides of the cutting plate (7) there is a reinforcement section (71) projecting outwardly from the side of the cutting plate and spaced laterally from the ends of the grooves (5, 6) in the drill head.

Abstract: A crown drill including a hollow cylindrical carrier body, which is formed of two coaxially arranged tubes connected with each other, and a cutting member attached to the carrier body and projecting axially beyond the leading end of the carrier body.

Abstract: A directional horizontal boring backreamer for enlarging an initial bore, including three equally spaced radially extending wings attach to a common axle, equally spaced around the axle, each wing including a plurality of cutters positioned along the wing for enlarging the bore, and attached to each wing is a gusset plate welded to the axle at the juncture of the wing and axle and to the wing for added bending strength to the wing. The gusset plates also including an internal passage way from the center passage of the axle to the outer edge of the wings to support and supply a series of fluid jets supplied by fluid for assistance in cutting during the backreaming operation.

Abstract: An auger bit for boring ski post holes having an elongated shank with a drill head fixed at a first end of the shank. The preferred drill head has diametrically opposed first and second open chip mouths, each defined by an advancing face and a trailing face of the drill head. The advancing face of the drill head may be oriented at a vertical rake angle and at a radial advance angle for propelling debris proximally from the drill head into and through the first and second chip mouths into first and second chip throats. The bit may include first and second excavating helices wound around the shank for a given number of rotations each at a given helix angle whereby first and second chip throats are formed. The second excavating helix may wind around the shank for a lesser number of rotations than does the first whereby a unitary chip throat succeeds the first and second chip throats. Preferably, the bit has an overall length greater than about fifteen inches and a shank which is hollow.

Abstract: A masonry drill bit having an improved insert geometry, insert orientation, and interface clearance for providing improved drill speed and penetration rate. The drill bit is adapted for use in drilling masonry or other hard, brittle material. The drill bit has an axially elongated body with a leading front end portion and a rear end portion. The rear end portion is adapted to be held by a tool holder. The body has at least one spiral groove cast in its exterior surface substantially along its length. The insert is embedded in the leading end of the body, extending generally diametrically across the leading end of the body, and centered about a latitudinal plane of the insert. The geometric design of the insert, the orientation of the insert relative to the drill bit, and the interface clearance between the insert and the grooves, reduces friction and heat; resists wear, fractures, and abrasive actions of the chips; increases design life of the elements; and enhances debris elimination.

Abstract: Drill for making a pole in the ground, whereby this drill (9) is provided with a passage (15) and whereby this drill has at the bottom a screw-shaped displacement part (11) of which the outside increases in radius upwardly, up to a diameter larger than that of the drill tube (8), characterized in that the displacement part (11) passes with its upper extremity into a cylindrical part (12) which is provided on its mantle with at least a screw blade (13) which runs in the shape of a screw in the same direction as the displacement part (11), but of which the pitch (S2) is larger than the pitch (S1) of the displacement part (11).

Abstract: An earth remediation auger (22) is adapted for boring into tight ground (28) at a contaminated site. The earth remediation auger (22) includes a soil mixer (36) with mixing holes (40), scraping blades (34), and fin cutters (32). The fin cutters (32) score the ground (28) before the scraping blades (34) break the scored ground (28) into chunks and pass the chunks onto the soil mixer (36). The earth remediation auger (22) has relief cutouts (50) for self-cleaning of clay based soils.

Abstract: A drill bit is proposed, in particular for the rotary-percussive drilling of preferably rock, concrete or the like, which includes a thin-walled cylindrical drilling body (106) open to the drilling side and a drill-bit base (20) extending essentially radially and having an axially arranged drill-bit shank (101) for fastening the drill bit. The drill-bit base (20) has an outer contour in the radial direction, which outer contour follows a curve shape which has at least one inflection point. Furthermore, a drill bit is proposed whose drill-bit base (20) has an outer contour which passes through a minimum in the radial direction, the drill-bit base being connected in the rising radially outer curve section of its outer contour to the cylindrical drilling body.

Abstract: Drilling augers comprise a tubular housing having an outer circumferential surface, with helical flighting mounted on the outer surface to effect drilling. Opposite ends of each auger terminate in a socket end connector and a plug end connector, the plug end connector of a succeeding auger received within the socket end connector to provide a connection between the augers. A circumferentially extending gasket seal is provided between the end of the plug end connector and a circumferentially extending rim on the socket end connector to prevent fluids from outside of the augers from leaking into the passage through the augers, and to prevent drilling fluids in the passage from leaking out. Pins carried by the socket end connector engage apertures in the plug end connector to provide a connection between the augers when the drilling string is withdrawn. Plug seals are snap fitted into the apertures and are held therein by a circumferentially extending rim engaging a surface surrounding the apertures.

Abstract: Soil displacement auger head for installing piles in the soil, having a tip, a displacement body having at least over a lower portion a core diameter increasing in diameter in a direction away from the tip, and at least one screw flange extending at least over the lower portion of the displacement body. To obtain a more efficient displacement, the pitch of the screw flange increases and the core diameter of the displacement body increases preferably discontinuously via a number of transition slopes.

Abstract: A drill rig for drilling in potentially hazardous areas includes a drill having conventional features such as a frame, a gear motor, gear box, and a drive. A hollow rotating shaft projects through the drive and frame. An auger, connected to the shaft is provided with a multiplicity of holes. An inert gas is supplied to the hollow shaft and directed from the rotating shaft to the holes in the auger. The inert gas flows down the hollow shaft, and then down the hollow auger and out through the holes in the bottom of the auger into the potentially hazardous area.

Abstract: A cutter for a trenchless boring apparatus includes a mount having a first end to be coupled to a free end of a drill pipe. A plurality of cutting teeth are secured to the mount with the teeth arranged in a helical pattern surrounding an axis of the mount.

Abstract: In an augering apparatus for rotating and advancing a cutting head longitudinally of the apparatus driven by a string of auger flights with helical flighting, an auger flight support comprising a plurality of radially extending support legs affixed to a bearing housing surrounding a bearing rotatably affixed to the auger drive shank disposed at one end of a two-ended auger flight to support the auger flight independently of the support provided by the auger flighting to reduce wear and tear of the helical flighting and to eliminate frictional drag of the string of auger flights.

Abstract: The instant invention is an improved cutter head with a salvageable end cap for hollow stem augers. The end cap includes a mechanism for retrieval upon completion of a drilling operation thereby allowing the end cap to include various bit formations so as to assist in the drilling operation. The side wall of the cutter head is modified to include a keyhole slot for maintaining of the end cap in a rigid position to prevent rotational movement.

Abstract: A cutting tool or drill bit (10) has a shank (12) with two ends. A chucking end (14) is on one end of the shank (12) and a cutting end (16) is on the other end of the shank (12). At least one flute (30) is formed on the shank (12) between the chucking (14) and cutting ends (16). The flute (30) includes a web (36) and a debris channel (32). The web (36) includes a first (38) and second (40) surface continuous with a debris channel side wall (34). The first surface (38) is substantially parallel to the shank longitudinal axis (18) and the second surface (40) is on an angle from about 100.degree. to about 120.degree. with respect to the shank longitudinal axis (18). The second surface forms the base of the debris channel or groove (32) with the debris channel side wall (34). The debris channel side wall (34) is on an angle from about 10.degree. to about 20.degree. with respect to the shank longitudinal axis (18).

Abstract: A drilling system employs spaced apart cutting members arranged in a helical pattern to form a helical thread within a rock bore. The thread is efficiently fragmented by a wedge-shaped trailing cutting member. Advantageously, a substantial portion of the rock is removed by the fracturing of the internal thread in the rock bore by the uppermost cutting member, taking advantage of the weakness of rock in tension. The rotational speed of the helical cutting system may be controlled as a function of the axial thrust applied to a pilot bit located in front of the helical cutting system.

Abstract: A vertical trencher having a cutter body with cutting teeth arranged in a spiral configuration on its circumference with an increasing rise angle, for excavating various size trenches, which is operable at high speed and efficiency, and suitable for use on hard and rocky ground. The cutter body is formed with a spiral-shaped concave channel, with grinding teeth attached to its outer edge. The grinding teeth cut soil and rock loose, so that pieces are scooped into the concave channel. The rise angle of the concave channel to the horizontal increases along the length of the cutter body. Thus, loose pieces of soil are transported upwardly along the concave channel at an increasing axial speed. The cutter body is connected at its upper end to a hydraulic engine mounted on the housing, which provides rotational power.

Abstract: A planting hole forming apparatus includes a central shaft having a longitudinal axis, a bottom leading end and an upper trailing end, and a discontinuous flighting comprising a plurality of flighting sections spiraling around the central shaft at spaced locations along the shaft adjacent the bottom leading end. Some form of drive mechanism, for example a hand-held drill, is used to rotate the central shaft about its longitudinal axis to thereby form the planting hole. The drive mechanism is chosen to accommodate the size of the central shaft and to supply the necessary torque to rotate the central shaft sufficiently to form the planting hole. The structure of the flighting sections is such that while the planting hole is being formed the soil is simultaneously pulverized with a substantial portion of the pulverized soil being left in the hole.

Abstract: A pilot bit for use with an auger bit in an auger bit assembly secured to the downhole end of tubular drill stem for drilling boreholes in earth formations comprises a tubular pilot bit body having a downhole end and an upper end at the axially opposite end of the body, the body being dimensioned to be telescopically received within an axial bore of an auger bit and being releasably connectable to the auger bit against axial and angular displacement, an axial throughbore extending through the body for telescopically receiving an earth sampling tool, a closure device secured to the downhole end of the pilot bit for opening and closing the throughbore, and pilot bit cutting teeth secured to the closure device.

Abstract: A rock drill is formed of an axially extending shank (2) with a drill head (1) at one end and chuck end (3) at the other end. The axially extending outside surface of the shank has at least one helically extending conveying groove (4, 5) and at least one helically extending land (6, 7). The land (6, 7) forms the radially outer surface of the shank (2). Grooves (8, 9) extending perpendicularly of the shank axis are formed in the surface of the land.

Abstract: A rock drill has an axially elongated shank (1) with a hard metal drill head (2) secured at one end. The transverse cross-section of the drill head is basically rectangular with cutters located along each of two diagonals of its cross-section. The cutters remove drillings from rock. The cutters include a main cutter (4) and two auxiliary cutters (5, 6) having the same rotational envelope curve.

Abstract: An axially elongated rock drill has a chucking shank section (1) at one end and a drilling tip (2) at the opposite end, helically arranged first grooves (3, 4) are located in the outside surface of the drill and extend from adjacent the drilling tip towards the chucking shank section. Helically arranged lands (R) are located between the first grooves and form the outside surface of the drill. The lands have helically arranged auxiliary second grooves located between helically arranged guidance regions (7, 8, 9, 10). Accordingly, the second grooves are spaced from the first grooves by the guidance regions. The width (BH) of the first grooves (3, 4) is approximately twice the total width (BG) of the lands, that is, the width of the two guidance regions and one second groove.

Abstract: A drilling tool and, in particular, a rock drill, which is of multi-part design, is proposed. In this, the drill head and/or the clamping shank is connected via a helical shank designed as a threaded rod.

Abstract: A device for facilitating the insertion of a beach umbrella in the sand includes a shaft formed as a helix about an axis of rotation with a handle attached to one end thereof. The curvature of the helix defines a major diameter and the shaft of the device is at least a quarter the size of the major diameter. The shaft is manually inserted in the sand and then withdrawn thereby forming a hole for the insertion of the beach umbrella support shaft.

Abstract: A system for simultaneously lining and cleaning an existing sewer pipe, and for laying horizontal pipe without digging a trench, includes a planetary gear assembly mounted on a drilling rig. A liner pipe or outer pipe which is to be laid underground is placed over an inner auger, with the forward end of the liner pipe located behind the auger drill bit. The opposite end of the auger is attached to the sun gear of the planetary gear assembly; and the outer pipe is secured to the ring gear of the assembly. The auger is rotated in one direction, causing the outer pipe to rotate in the other direction; and the pipe and auger are pushed simultaneously through the pipe to be lined or through the soil. Once a section of auger and liner pipe have been pushed in place, the planetary gear assembly is disconnected from the auger and the liner pipe, new sections of auger and liner pipe are connected to the existing sections at one end, and to the planetary gear assembly at the other end.

Abstract: A drilling tool and, in particular, a rock drill for the creation of breaches in concrete or masonry for the use of drill hammers is proposed, which is configured as a cross drill bit having four cutting fins. In order to optimize drilling capacity, the drilling tool is provided with a cross drilling head which merges in one piece into a conveyor spiral matched to the drill head. A purpose-specific cutting element facing serves to optimize the drilling capacity.

Abstract: A boring tube has at least one tubular base body having a throughgoing longitudinal passage and an outer side and a coil arranged on the outer side of the base body and extending over its whole length. The coil has a pitch of 1 m-3 m and a radial width which starting from the outer side of the base body is at least 10 mm.

Abstract: A ground fracturing probe to form fractures in subsurface formations includes an elongate, hollow body with a conical penetrating tip at its distal end. A threaded tool joint is at the other end of the body to allow the probe to be coupled to the drill string of a drilling rig. A helical flight is on the exterior surface of the body and extends along a portion of the body length between the tool joint and the penetrating tip. The helical flight varies in diameter over its length to define a cutting zone adjacent the penetrating tip, an injection zone above the cutting zone and a sealing zone above the injection zone. The helical flight increases in diameter in the cutting zone from the tip to the injection zone but decreases abruptly in diameter at the injection zone. The diameter of the flight remains constant in the injection zone and increases in diameter at the interface between the injection zone and the sealing zone.

Abstract: A rock bit is provided that comprises a generally cylindrical body with a leading end for boring in a rock formation and a trailing end for connection to a drill rod. The body has a generally cylindrical outside surface and comprises a plurality of parallel longitudinal grooves circumferentially spaced around the outside surface and extending from the leading end to the trailing end. The grooves have a depth that increases from the leading end to the trailing end such that the cross-sectional area of the grooves also increases towards the trailing end of the body of the bit. The body also comprises at least one channel machined in the outside surface of the body that extends between adjacent pairs of longitudinal grooves at an oblique angle to the grooves.

Abstract: The invention directed to a portable handheld drilling apparatus for receiving and driving a drill which can encounter a drilling resistance during a drilling operation thereby causing the drilling apparatus to undergo an unwanted rotational movement.

Abstract: A well clean-out tool includes a cylindrical member in which a helical conveyor screw is arranged for vertical sliding movement relative to the cylindrical member. The tool is lowered into a well bore until the shoe contacts debris within the bore. At that time, the screw is caused to descend relative to the cylindrical member, whereupon a lower end of the screw projects slightly below a lower end of the cylindrical member, and a rotary coupling between the screw and the cylindrical member is released, and a spring is caused to store energy. Thereafter, the screw is rotated relative to the cylindrical member, while the spring presses the cylindrical member against the debris in order to resist rotation of the cylindrical member. The screw projects only slightly downwardly beyond the lower end of the cylindrical member, e.g., less than one inch, in order to convey debris upwardly within the cylindrical member.

Abstract: A rock drill has an axially extending shank (1) with a drill head (2) on one end. The drill head (2) has an end face (3) with a cutting blade (4) and cutting pins (5) extending outwardly from the end face in the drilling direction. The cutting blade (4) extends diametrically across the end face and projects radially outwardly from the drill head (2) and axially outwardly from the end face (3). The cutting pins (5) are arranged on a diameter of the drill head which forms an acute angle relative to the cutting blade (4). Due to the acute angle between the cutting pins and the diametrically arranged cutting blade, removal grooves extending axially from the end face can be enlarged.

Abstract: An auger cutter head includes a rotatable body that is mountable on an auger and a plurality of cutting assemblies spaced about the outer wall of the rotatable body to drill a hole in the ground as the auger cutter head is rotated and advanced into the ground. Two of the cutting assemblies include outside chisel bits positioned to ream or gauge the hole as the cutter head is rotated and advanced. All of the flighting sections, bit, blocks, and blade assemblies provided in the cutting assemblies are offset in a radially inward direction relative to the two outside chisel bits to reduce the wear and tear on those components. Each of the chisel bits is oriented to rotate relative to its bit block about a predetermined axis of rotation to reduce wear caused by uneven loading on the rotatable chisel bits during drilling of the hole.

Abstract: A replaceable digging tooth for an earth auger including a generally oblong body member and a shank depending from the body member and receivable in a support block of the earth auger. The body member includes an elongated leading surface, an elongated trailing surface and first and second side surfaces. The leading surface, trailing surface and first and second side surfaces terminate in a forward working face having a plurality of inserts. Each insert has a generally cylindrical portion integral a top portion which tapers to a point to form a conical tip. The tips of the inserts are aligned to define a linear cutting line which is inclined with respect to a reference plane perpendicular to the axis of the shank and the axes of the inserts are aligned parallel to form a cutting plane which is inclined with respect to the reference plane.

Abstract: In the present invention are disclosed a hollow steel pile having an open extremity end with a helical projection composed of a round rod or rectangular rod of its height less than 20 mm arranged at an outer circumference of the pile or at both outer circumference of the pile and inner circumference of the pile at a length part less than ten times of s diameter of the pile, a method for fixing the inner circumferential projection and a pile execution method using such a pile as above. This hollow steel pile may preferably be used as a friction pile and a supporting pile, no vibration and noise are found during its execution of work, a better workalility is assured, a cost of execution of work is less expensive and this process is suitable for performing in a narrow site.

Abstract: An earth anchor apparatus includes a hub having a longitudinal axis and first and second axial ends, and a load-bearing helix affixed to the hub. The load-bearing helix includes a generally radially extending leading edge adjacent the first end of the hub, a generally radially extending trailing edge adjacent the second end of the hub, an inner circumferential section connected to the hub, and an outer circumferential section extending radially outward from the inner circumferential section and having an outer circumferential edge separated from the inner section. A pair of opposed surfaces extend between the inner section and the outer edge and define a thickness of the helix. The thickness of the helix at the trailing edge is greater adjacent the inner circumferential section than at the outer circumferential edge, and the thickness of the helix adjacent the inner circumferential section is greater at the trailing edge of the helix than at the leading edge.

Abstract: An auger planter is provided for forming small holes in the earth for the planting of flower bulbs and the like. The auger includes a central shaft and a single flighting having its leading and trailing ends truncated. When used, the single flighted auger exhibits minimal eccentric orbital rotation and minimizes inadvertent injury to the user.

Abstract: The drill bit for producing a cylindrical drilled hole, especially in concrete, has a shank and a drilling head at one end of the shank provided with at least one helically extending drilling dust groove. At least two bulb-like shank enlargements (6,7) are provided on the shank (5) arranged in succession axially. Each of the shank enlargements (6,7) has the same maximum diameter and the drilling head has a drilling head diameter which is at least as great as the maximum diameter of the shank enlargements (6,7). Advantageously two drilling dust grooves with semicircular cross sections are provided on the shank displaced from each other radially by about 180.degree. to form a cross member with cutting edges on the drilling dust grooves.

Abstract: An auger planter is provided for forming small holes in the earth for the planting of flower bulbs and the like. The auger includes a central shaft and a single flighting having its leading and trailing ends truncated. When used, the single flighted auger exhibits minimal eccentric orbital rotation and minimizes inadvertent injury to the user.

Abstract: Ice auger cutters include a shaft having a handle connected to one end for rotating the shaft about its axis, cutting elements secured to an opposite end of the shaft positioned radially outwardly from the axis, and an adjustable stop coaxially positioned between the cutting elements to control the penetration or feed rate of the cutter according to the density and temperature of the ice and strength of the operator.

Abstract: An apparatus for piling a cast-in-place pile includes an earth auger main body and an auger head. The earth auger main body includes a hollow shaft, a spiral screw blade provided about the hollow shaft, a spiral belt provided on an outer circumference of the spiral screw blade and in parallel with an outer circumferential surface of the hollow shaft. The auger head is connected to a lower end of the earth auger main body and includes a holow shaft, one or two spiral screw blades provided about the hollow shaft, one or two spiral belts provided on outer circumferences of the spiral screw blades and in parallel with the outer circumferential surface of the hollow shaft, and excavating bits provided at a lower end of the spiral screw blades, and device for preventing excavated earth and sand from flowing in a return direction when the auger head is rotated in a reverse direction.

Abstract: A device for facilitating the retrieval of a drill bit from a crooked hole, a soft rock or a broken rock formation is disclosed. The device is secured to a drill string at one end and to a drill bit an an opposite end. The device includes a cylindrical member having a helical member of gradually increasing radial thickness secured about its periphery. The helical member has a plurality of hardened cutter members secured to and projecting from its periphery. The radial thickness of the helical member is greatest at that section of the device closest to the drill bit and least at that section of the device closest to the drill string. The device clears obstructions in the bore hole above the drill bit to ease the removal of the bit from the hole, while at the same time, the device avoids enlarging the bore hole on either the advancing or retrieving trip of the drill string. The device further serves to maintain alignment of the drill string during advancement into and retrieval from the bore hole.

Abstract: A tapered auger shredder which includes a frame defining a grinding chamber with a front wall having a centrally-located discharge opening and a rear wall mounting a powered auger screw having a flighted shaft extending through the chamber and into the discharge opening. The auger screw and shaft are tapered and the screw flight is correspondingly tapered so that the volume pumped by the screw along the length of the shaft remains substantially constant, or the rate of compression is substantially reduced, to provide consistent flow of material to the discharge opening and reduce build up of material against the front wall. In a preferred embodiment, the screw includes a torque transmission collar which extends between a disc-shaped base plate supporting the screw and the first flight turn and acts to prevent jamming of material between the base plate and underside of the first turn as well as transmit rotational torque from the disc to the shaft and flight.