Abstract: A short radius drilling tool and a trajectory-controllable lateral drilling tool and method, including a lateral drilling section with high passing ability and a power transmission section, wherein the lateral drilling section with high passing ability can drill the extension well section of a short to ultra-short radius well section that extends laterally from a main wellbore. The designed trajectory-controllable lateral drilling tool allows a wellbore to be subjected to directional drilling with a short to ultra-short radius from a tail end or any position of the original wellbore trajectory, and then implements lateral extension drilling.

Abstract: A system and method for installing an aggregate pier in a soil matrix includes a pipe configured to interface with a torque driver for rotating the pipe. A helix is disposed on the pipe and configured to advance/withdraw the pipe based on direction of rotation. A compacting device is disposed between the distal end of the pipe and the helix. It extends radially outward and upward. In some embodiments, the compacting device is configured as a frustum. A lift in an aggregate pier is formed by rotating the pipe in a second direction to withdraw a portion of the pipe from the soil matrix thereby creating a void; (b) filling the void with aggregate; (c) rotating the pipe in the first direction to advance the pipe. The compacting device contacts the aggregate disposed in the void and imparts an axial and radial force.

Abstract: The invention provides a transmission mechanism for an electric drill and the electric drill including the transmission mechanism. The transmission mechanism includes a primary planet carrier, a gear assembly, a secondary planet carrier, and a secondary gear assembly. The gear assembly comprises a primary gear ring and a primary gear set located in the primary gear ring. The primary gear set has two primary planetary gear sets mounted on the primary planetary gear shaft. The secondary planet carrier is provided with secondary planetary gear shafts and an output shaft. The secondary gear assembly includes a secondary gear ring and a secondary planetary gear set. The secondary planetary gear set is pivotably mounted on the secondary planetary gear shafts, an outer side of the secondary planetary gear set engages with the secondary gear ring, and an inner side of thereof engages with the sun gear.

Abstract: A cutting head includes a main body that is attachable to an ice drill shaft at a top side. The main body includes a bottom side that has a bottom peripheral surface. The cutting head includes at least one cutting edge that is disposed on the main body. The cutting edge is configured to perform a cutting operation at the bottom side of the main body. The cutting head includes a cutting rate control pad that is disposed on the bottom side of the main body. The cutting rate control pad extends away from the bottom peripheral surface.

Abstract: A rotary cutting tool with a shank and an interchangeable cutting tip, wherein the shank includes a pocket which receives the interchangeable cutting tip via an interference fit. The pocket includes two centering wall portions which, when viewed along a central longitudinal axis, are oriented at a first angle with respect to one another, the first angle being greater than zero. The interchangeable cutting tip is axially displaceable between: an initial position, assumed upon being received in the pocket of the shank; a clamped position, wherein the interchangeable cutting tip is fixedly held with respect to the shank; and a bump-off position, wherein the interchangeable cutting tip is not fixedly held. A holding element holds the interchangeable cutting tip in the clamped position, and a bump-off element displaces the interchangeable cutting tip between the clamped position and the bump-off position. Other variants and embodiments are broadly contemplated herein.

Abstract: A drilling tool, in particular a rock drilling tool, for a portable machine tool includes a drill head, a drill shaft connected to the drill head, and a rotational axis. The drill head in one embodiment is a hard metal drill head, and the drill shaft in one embodiment is connected integrally with the drill head. The drill shaft is configured as one piece, has a guide section with guide groove winding in a spiral-shaped about the drill shaft for transporting away drilling dust, and has a securing section that is configured to detachably secure the drilling tool to a machine tool. The guide section has a diameter reinforcement at a drill head support region of the guide section neighboring the drill head.

Abstract: A quick-changing brazed drill includes a drill body and a quick-changing joint. The drill body is connected to the quick-changing joint detachably, and a vent hole is provided at a connection point between the drill body and the quick-changing joint. The drill body has a cylindrical structure, an interior of a front end of the drill body is hollow, and an outer side of the front end of the drill body is provided with 2-6 grooves. The quick-changing joint includes a transition block and a rear cover; a rear end of the transition block is connected to the rear cover by an external thread; a snap-fit area is provided between the transition block and the rear cover; a middle portion of the transition block is provided with a first threaded hole and is connected to a rear end of the drill body.

Abstract: A drill bit for drilling into masonry or rock includes a drilling head at its forward end, a clamping shank at its rearward end, and a helical conveying portion extending between the drilling head and the shank. The helical conveying portion includes at least two helically extending flutes separated by at least two helically extending webs. The helical conveying portion has a changeover portion, a pre-changeover portion between the drilling head and the changeover portion, and a post-changeover portion between the changeover portion and the shank. In the pre-changeover portion, the flutes have a pre-changeover pitch, the first web has a first pre-changeover web width ?, and the second web has a second pre-changeover web width ??. In the post-changeover portion, the flutes have a post-changeover pitch, the first web has a first post-changeover web width ?, and the second web has a second post-changeover web width ??.

Abstract: A method for retrofitting a wind turbine foundation is provided. The foundation comprises a first substantially elongated pile (31) in the ground. The method further comprises: arranging a lower end of an elongated channel (41) of a second substantially elongated pile (40) around the first pile (31), wherein the elongated channel (41) extends substantially along a longitudinal direction of the second pile (40), wherein the channel (41) is configured to receive at least a portion of the first pile. The method further comprises lowering the second pile (40) such that the elongated channel (41) surrounds at least a portion of the first pile (31). Finally, the second pile (40) is driven into the ground (35).

Abstract: A rotary tool may include a body, the body may include a cutting edge and a first groove. The first groove may include a first region having a first helix angle, a second region having a second helix angle, a third region having a third helix angle, a fourth region having a fourth helix angle, and a fifth region having a fifth helix angle. The fourth helix angle and the fifth helix angle may each decrease from a side of a first end toward a second end. A decreasing range of a value of the fourth helix angle of the fourth region may be less than a decreasing range of a value of the fifth helix angle of the fifth region. A length of the fourth region may be greater than a length of the fifth region.

Abstract: A drilling tool, in particular a rock drilling tool, for a portable machine tool, includes an axis of rotation, at least one spiral path, and at least one wear surface transition. The at least one spiral path is coiled about the axis of rotation along the axis of rotation and includes at least one wear surface having at least one bandwidth. There is a change in the at least one bandwidth of the at least one wear surface at a position of the at least one wear surface transition.

Abstract: A helical auger flight has an inner edge, an outer edge, an inner face, an outer face, and a leading extremity that includes a prominence and a leading edge that extends from the outer edge to the prominence. The prominence extends outward from the leading edge of the leading extremity to an outer end having an upturned jut. A wear plate is releasably connected to the inner face of the helical auger flight. The wear plate extends from the outer edge of the helical auger flight to the prominence. A front extremity of the wear plate extends forwardly of the leading edge of the helical auger flight so as to be in a shielding relationship with respect to the leading edge of the helical auger flight, and a nose of the front extremity of the wear plated is seated in direct contact against a contact surface of the jut.

Abstract: Provided is a fastening structure having a wide application range and a high degree of freedom of design. A fastening structure includes: a head including a first end surface and a first screw part formed on the first end surface; and a shank including a second end surface and a second screw part formed on the second end surface and threadedly engaging with the first screw part. The first end surface includes a first principal surface oriented in an axial direction of the first screw part and a first step surface oriented in a rotational direction of the first screw part. The second end surface includes a second principal surface oriented in an axial direction of the second screw part and a second step surface oriented in a rotational direction of the second screw part. The first and second principal surfaces face each other and the first and second step surfaces face each other when the first screw part threadedly engages with the second screw part.

Abstract: A drilling tool is configured to perform drilling and/or percussive work on materials such as stone, concrete and/or reinforced concrete. The drilling tool has a fastening region and a working region. The working region has a working body and at least one cutting element projecting axially and/or radially in relation to the working body. The at least one cutting element has at least one first cutting edge and at least one second cutting edge. The at least one second cutting edge is configured to serve as a replacement cutting edge and/or as an auxiliary cutting edge, and the at least one second cutting edge is set back, at least partly, in relation to the at least one first cutting edge of the drilling tool, axially along a longitudinal axis of the drilling tool, in a direction towards the fastening region.

Abstract: A replaceable face-milling head configured for rotating about a central rotation axis AR. The head includes a cutting portion and an integrally formed threaded shank-connector portion, the latter of which being configured for connecting to a shank. A length-diameter ratio LDR, defined as a cutting portion length LC divided by a cutting portion diameter DE, fulfills the condition: LDR?1.00.

Abstract: The twist drill (1) has a drilling head (3), a continuous two-flute, three-flute to six-flute helix (4) and an insertion end (5) that are arranged consecutively on a drill axis (2). The helix (4) has a radial outer dimension (18) that varies periodically two, three to six times per revolution around the drill axis (2). The invention also relates to a production method for such a drill.

Abstract: Golf club heads with patterned face plates described herein. Other examples, embodiments and related methods are also disclosed herein.

Abstract: This rotary press-in steel pipe pile includes: a steel pipe; a first blade which is formed in a substantially helical shape on the steel pipe so as to be positioned close to the distal end the steel pipe and in which a first sectorial gap having a central angle is formed in a circumferential direction thereof; and a second blade which is formed in a substantially helical shape on the steel pipe so as to be positioned close to the rear end of the steel pipe with respect to the first blade and in which a second sectorial gap having a central angle is formed in a circumferential direction thereof. The first sectorial gap of the first blade and the second sectorial gap of the second blade are disposed at positions that do not overlap in a circumferential direction, and the central angle of the second sectorial gap is set to be smaller than the central angle of the first sectorial gap.

Abstract: The modular carrier tool (2), in particular drilling tool, extends along a central longitudinal axis (4) in axial direction (6) and comprises a carrier (8) as well as a tool head (10) that can be reversibly mounted on the front-end of the carrier (8). The carrier (8) has a head retainer (14) for the insertion of the tool head (10) as well as clamping webs (24), which radially delimit the head retainer (14) and also have bearing surfaces (28). The tool head (10) comprises clamping surfaces (35) extending in axial direction as well as underhead bearing surfaces (34). In a mounted state the clamping webs (24) clamp the tool head (10) in radial direction to the clamping surfaces (35) and the underhead bearing surfaces (34) are pressed against the bearing surfaces (28).

Abstract: A method for manufacturing a roof-bolt drill bit includes providing a bit body rotatable about a rotational axis in a rotational direction, the rotational axis extending between a forward end and a rearward end of the bit body, the bit body comprising a mounting region for mounting at least one cutting element to the bit body. The method includes forming at least one primary debris channel in the bit body, the at least one primary debris channel extending from adjacent the mounting region to a portion of the bit body located axially rearward from the mounting region, and forming at least one secondary debris channel in the bit body by machining a portion of the bit body along a substantially straight path to form an intersection with the primary debris channel.

Abstract: The invention relates to an anchoring device wherein a positioning plate (5), intended for bearing on the ground surface, is mounted onto a hollow rod (2). The rod consecutively supports, from the positioning plate (5) to the free end (22), at least one helical force disk (6) then one helical penetration disk (8). Said anchoring device is characterized in that the rod extends after the helical penetration disk opposite the plate (5). Said anchoring device is moreover characterized in that a bit (4) is placed on the free end of said rod so that a first portion of the rod (2), capable of being screwed into at least one first ground layer, extends from the plate (5) to the helical penetration disk and moreover so that a second portion of the rod (2), capable of being anchored in a second ground layer, extends from the helical penetration disk (8) to the bit (4).

Abstract: Described herein is an inner tube for a core barrel which has a structure adapted to retain lubricant for lubricating a sampled core. The internal surface of the inner tube includes a plurality of structures to retain lubricant adjacent a core received in the inner tube. An example structure is multiple alveoli in which lubricant is retained.

Abstract: A helical screw pile includes a longitudinal shaft having a top end and a bottom end with a plurality of helical plates arranged on the shaft in increasing diameter from the top to the bottom. The largest diameter helical plate is located toward the bottom of the shaft. A second helical plate having a diameter smaller than that of the first plate is located above the first helical plate. A smaller third helical plate is located above the second helical plate so that the smallest is located toward the top of the shaft. The helical plates can be spaced apart along the shaft or coupled together in an end-to-end manner to form a continuous helix.

Abstract: Golf club heads with patterned face plates described herein. Other examples, embodiments and related methods are also disclosed herein.

Abstract: An electric auger including an auger assembly with a coupling assembly at a proximal end, a cutting assembly having at least one cutting blade located at a distal end, and a helical flight located between the proximal end and the distal end. The electric power head includes an A/C motor with a drive shaft configured to mechanically couple with the proximal end of the auger assembly. An on-board 36-volt DC battery pack powers the A/C motor. A controller includes an inverter that converts DC power to A/C power for the A/C motor. The ratio of cubic inches of ice cut per battery ampere-hour per weight in pounds of the electric auger is at least about 900 (inches3/ampere-hour/pounds).

Abstract: In a rotary drill, the drill is provided with at least one groove, which has a center lying on the axis of rotation of the drill. The two end points of the groove define a groove width, and the drill is provided with two or more cutting edges. Two cutting angles are defined. The groove has a left side and a right side. The rotary drill can be used in a rotary drilling machine. The drill can be provided with a drill bit.

Abstract: A reaming bit designed to operate with low torque fluctuation when driven with a turbine at speeds in the order of 300-600 RPM and above features a profile that is arcuate from the gauge dimension to the nose area or alternatively has a blunt straight taper section but with a ratio of profile length (PL) to bit size (BS) of under 0.75. The blades extend into a concave cone and the cutting structure continues along the blades towards the center. The blades have a step near the gauge section to increase the exposure of the blade cutting structure. An array of protrusions are disposed parallel to and behind the cutting structure to increase high speed stability and adjacent the blade step transition to protect outer casing on run in.

Abstract: A multi-tasking downhole rod guide for centralizing a downhole pump rod production tubing within production tubing, while simultaneously reducing abrasion and deterioration of the production tubing and engendering auxiliary pump-boosting functions. The rod guide is configured with an elongate helix having a continuous trough-like channel through which hydrocarbons flow upwardly under high pressure. As the pressurized hydrocarbons flow through a succession of plates at each equidistant helical level, the elongate helix rotates synchronously with the upwardly flowing hydrocarbons within the production tubing string.

Abstract: Disclosed in this specification is a method and apparatus for placing an auger grouted displacement pile or helical pile in soil. The pile has an elongated shaft with at least one lateral compaction protrusion which establishes a regular bore diameter in the supporting medium. The pile also has a helical blade configured to move the pile into the supporting medium. The bottom of the shaft includes means for forming irregularities in the bore diameter after compaction by the lateral compaction protrusion. The bore is filled with grout while leaving the pile in the soil.

Abstract: A drill bit for enhancing drilling operations, where the drill bit includes a bit body configured for coupling to a drillstring, and a bit face disposed on an end of the bit body with at least one cutting structure attached thereto. There is a fluid guide operatively connected to the drill bit and disposed above the end of the bit body, where the fluid guide includes at least one nozzle disposed therein that is in fluid communication with a fluid cavity disposed in the drill bit, and where the fluid guide is configured to induce distribution of fluid flow in a flow regime above the drill bit.

Abstract: The Smart Reamer® Tool, Apparatus or Method is used to underream an oil or natural gas well while interlinked calipers and calibration sensors simultaneously record data relating to the geometry of the drilling operation (well diameter, diameter of the underreamed zone) and drilling fluid properties (density). Further sensors provide data on the relative position of the cutting and stabilizing blocks. Other sensors measure vibration data. All the sensors are interlinked by means of microprocessors which compare and correlate said data to automatically verify and deliver a desired wellbore diameter without the need to unnecessarily stop drilling or trip out of the hole.

Abstract: A cutting device for use with installation of helical ground anchors designed to cut through rock. The invention has carbide steel cutting tips attached to the distal end of a shaft extending below the end in order to make a first cut through rock along the axis of rotation of the shaft. Helically shaped plates are attached to the shaft at a distance above the shaft set of cutting tips. Attached along the outer edge of the helix are additional carbide steel cutting tips that extend below the bottom surface of the helix and cut along the axis of rotation of the shaft. The present invention allows for the installation of helical ground anchor supports at proper depths without deviation, in situations where the path is obstructed by rock or other hard materials.

Abstract: A downhole dual cutting reamer for bidirectional reaming of a wellbore with a tubular body with two cutting sections between end segments. Each cutting section has a plurality of helical blades separated by a flute, and wherein the helical blades are formed from at least two spiral angled sections connected together, with cutting components on the spiral angled sections. The cutting components can be polydiamond cutter nodes, high strength carbide cutting nodes, and tungsten carbide facing coating. The outer diameter of each cutting section is larger than the outer diameter of each of the end segments.

Abstract: An auger for digging holes that minimizes the amount of loose dirt excavated in and around the dug hole. The auger comprises an elongated shaft body whose axial longitudinal center is disposed in a parallel offset position from the axial engagement line of orientation with the driving source for rotationally driving the auger. The shaft body of the auger revolves in an eccentric lateral orbit as the auger rotates which digs the hole by pushing and widening the dirt in the hole rather than cutting and scraping. The distal end of the auger has a tapered configuration for initial penetration into the ground. The eccentric movement of the shaft body of the auger helps to compact the walls of the hole being dug.

Abstract: A steel pipe pile having pile bearing capacity without disturbing the surrounding ground during installation. The steel pipe pile including a first steel pipe pile that has a hollow steel pipe and a first helical fin on the outer periphery thereof from one end toward the other end at a constantly equal pitch; and a second steel pipe pile that has a hollow steel pipe and a helical fin on the outer periphery thereof from one end toward the other end at a constantly equal pitch and that is joined at an end to the other end of the first steel pipe pile, the pitch of the first helical fin and the pitch of the second helical fin being equal, and the first helical fin and second helical fin being continuous along an imaginary helix at the joint between the first steel pipe pile and the second steel pipe pile.

Abstract: The invention relates to a drill for realizing a partially tapered bore hole in a soil covering a hardpan layer. The drill comprises a rotatable drivable unit that is provided with a carrying structure and a multiple number of cutting elements carried by the carrying structure. The multiple number of cutting elements are arranged along a line extending substantially radially and outwardly from a central axis of the rotatable drivable unit. Further, lower ends of cutting elements in a radial inner section are mainly positioned in a plane transversely to the rotation axis of the rotatable drivable unit. Lower ends of cutting elements in a radial outer section are mainly positioned in a downwardly tapered surface having a symmetry axis coinciding with the rotation axis of the rotatable drivable unit. The lower ends of the cutting elements may subscribe, during rotation, a truncated cone surface.

Abstract: Downhole drilling tools designed and manufactured to reduce bit axial force and torque and to enhance drilling efficiency comprising laying out some cutters in one spiral direction of rotation about a bit rotational axis and other cutters in an opposite spiral direction of rotation; evaluating forces acting on cutters during simulated engagement with a downhole formation (straight and transitional drilling); and modifying cutter layout with respect to a spiral direction of rotation. Some embodiments further comprise, prior to simulation, placing cutters in cutter groups/sets at respective locations to obtain a level of force balance. Multilevel force balanced downhole drilling tools may be designed using five respective simulations: cutter group level, neighbor cutter group level, cutter set level, group of N (N=3 or N=4) consecutive cutters level and all cutters level. Cutter layout procedures and algorithms to minimize respective bit forces and in some embodiments to obtain force balance are described.

Abstract: A down-the-hole assembly includes a housing having a central axis and a mechanical gear box positioned within the housing. The mechanical gear box is coupled to the housing such that rotation of the housing at a first rotational rate provides a rotary input to the mechanical gear box. A rotary cutting bit is coupled to the mechanical gear box. The mechanical gear box is configured to rotate said rotary cutting bit at a second rotational rate in response to that rotary input from the housing. The second rotational rate is greater than the first rotational rate. The mechanical gear box is also further configured to cause the rotary cutting bit to orbit about the central axis of the housing.

Abstract: A downhole tool for bidirectional reaming of a wellbore with a tubular body with a central cutting section between a first end segment and a second end segment, wherein the central cutting section has a plurality of helical blades separated by flute sections, and wherein the helical blades each have at least two spiral angled sections connected together, polydiamond cutter nodes, high strength carbide cutting nodes, tungsten carbide hardfacing coating or combinations thereof on the helical blades, and wherein the outer diameter of the central cutting section is larger than the outer diameter of each of the end segments.

Abstract: The invention provides a cutting head for a drill bit, the cutting head comprising four substantially identically shaped cutting arms extending radially from a common central axial point, each cutting arm comprising a cutting edge extending outwardly and axially backwards from the common central axial point. The cutting edges are equiangularly spaced apart from each other about the central axis of the cutting head. Each cutting arm further comprises a side chamfer extending between its radially outer face and its rotationally trailing side face.

Abstract: The helical drill bit defines a helical end section of a helical structure formed at its periphery by an auger of an excavation assembly, and it is associated or associate with a support portion of the auger. Such a support portion defines a proximal section of the helical structure, which has an extension substantially centred around a longitudinal axis (X-X). The helical drill bit is adapted to rotate about the longitudinal axis (X-X) together with the support portion so as to drill a hole in the ground. The helical end section extends around an extremity axis (Y-Y; ?-?) that is not aligned relative to the longitudinal axis (X-X).

Abstract: A helical screw pile includes a longitudinal shaft having a top end and a bottom end with a plurality of helical plates arranged on the shaft in increasing diameter from the top to the bottom. The first helical plate is located toward the bottom of the shaft and has the largest diameter. The second helical plate is located above the first helical plate and has a diameter smaller than that of the first plate. The third helical plate is located above the second helical plate and has a diameter smaller than that of the second plate. The helical plate with the smallest diameter is located toward the top of the shaft. The distance between the first helical plate and the second helical plate is larger than the distance between the second helical plate and the third helical plate.

Abstract: A purpose of the invention is to provide a spiral piece of steel having high mechanical strength and being capable of easily making smaller the pitch intervals of twisted portions (spiral blade portions) even without changing the twist angle, and also to provide an application product thereof and a method for manufacturing the spiral piece of steel.

Abstract: A horizontal directional drilling sonde housing has a cavity for receiving a sonde. Signal channels extend from the cavity to an exterior of the housing. A polymer lines at least part of the cavity and fills the signal channels. The drilling tool has a bit body and a drilling body. The two bodies have respective lateral surfaces which engage each other to prevent the transverse movement of the drilling body relative to the bit body during operations. The drill bit has a forward extending drill tooth, which drill tooth is removable from a bore. A spacer is located in the bore between the bottom end of the bore and the tooth. The drilling bit has buttons located on the side in a spiral configuration about a longitudinal axis of the bit.

Abstract: Excavation equipment for the construction of compaction piles includes a tool mounted at the end of a drilling rod; the tool is constituted by a shaft (10) provided on its end with digging teeth (12) and with at least a plate (14) for collecting debris rotating between an open position during the excavation and closed during the ascent of the tool. A screw (17, 18, 17?, 18?, 20); is of the type having at least two principles (17, 18, 20), in the upper part (20) fixed directly on the shaft (10) and in the lower part (17, 18) fixed on a cylindrical element (16) inserted on the shaft. A compactor (19) is positioned on the screw (17, 18) of the cylindrical element (16). The shaft rotates between two positions displaced between them, one corresponding to the excavation condition and the other to the ascent one; each of the at least two-principle screws of the shaft (20) constitutes the continuation of a corresponding screw (17, 18) of the cylindrical body (16) depending on the angular position of the shaft (10).

Abstract: In one aspect of the invention, a drilling assembly comprises a head located on a rotational axis of the assembly and comprises at least one head element. At least one blade extends distally from the head. A plurality of blade degradation elements are rotationally supported on the blade. Each degradation element comprises an attack angle that affects the penetration rate of each degradation element and a laterally offset angle that primarily affects the rotational rate of each degradation element within their holders. The drilling assembly comprises a central cutting region. The blade degradation elements within the central cutting region form an attack angle of 15 to 20 degrees with the rotational axis of the drilling assembly.

Abstract: A well bore reamer has an elongated body for coupling between members of a well string, a first set of cutting elements on the body at a fixed position, a second set of cutting elements on a sleeve closing around a sleeve carrying portion of the elongated body. The sleeve is slidable along a longitudinal axis of the body and rotatable thereabout. A lower clutch mechanism operates between the sleeve and the elongated body at a bottom end of the body's sleeve carrying portion to block rotation of the sleeve relative to the elongated body in a predetermined direction about the longitudinal axis under sliding of the sleeve into a lowered position adjacent said bottom end of the sleeve carrying portion.

Abstract: A multifunctional screw drill and reaming device, for the testing of the structure and composition of various soil types, as well as for sampling and boring, extracting and injecting of gases and various types of chemicals as well as liquids, slurry, granules and solids. Screws can be hydraulically, pneumatically, mechanically, electrically or manually driven. Dependent upon the operation, the secondary screws (2) can rotate and change position or rotational direction within the primary screw's bore (1), or both primary (1) and secondary screws (2) can be coupled and rotate as one unit.

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

Abstract: The invention relates to an auger having a cutting means for removing ground material and a conveyor flight for conveying the ground material removed by the cutting means, whereby the conveyor flight has several conveyor flight pieces which are arranged along an axial direction of the auger and connected to each other in a detachable manner. Provision is made for a central receiving shaft, on which the cutting means is arranged in a rotationally fixed manner. Furthermore, provision is made for the conveyor flight pieces of the conveyor flight to have a mounting pipe each, which is mounted onto the central receiving shaft, whereby the central receiving shaft projects through the mounting pipe, and for the conveyor flight pieces to be connected in a rotationally fixed manner to the central receiving shaft.