Abstract: The drilling tool includes a circular-cylindrical casing pipe; an annular ring bit disposed at a leading end of the casing pipe so as to be coaxial with the casing pipe and rotatable around a central axis of the casing pipe; and a pilot bit inserted into the casing pipe and has a leading end disposed at an inner peripheral part of the ring bit. The ring bit is engaged with the pilot bit in a rotational direction, and thereby is rotatable integrally with the pilot bit and is locked to the leading end of the pilot bit. Drilling tips are mounted on the leading ends of the pilot bit and the ring bit, and first drilling tips at an outermost periphery of the pilot bit and second drilling tips at an innermost periphery of the ring bit overlap each other in a rotational trajectory around the central axis.

Abstract: An apparatus for drilling a hole in the ground has a hammer drill installed at a bottom of a rod assembled in multi-stages at support structure on the ground. The hammer drill has a pilot hammer drill and a reamer hammer drill coupled to each other through a key structure formed in the vertical direction so as to allow simultaneous rotations and up-and-down movements relative to each other.

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 system and method for boring a hole in rock with a digger derrick; which utilizes a hollow stem auger, a kelly bar, and a core barrel with a top support member with a hole therein for receiving the kelly bar with a detachable central pilot bit thereon which is translatable up and down with respect to the core barrel as the kelly bar and auger are manipulated. The kelly bar is selectively positionable with respect to the auger so as to allow the ability to retract the pilot bit inward into the core barrel and to shorten the separation between the pilot bit and the auger.

Abstract: A method and apparatus for constructing large vertical boreholes and underground cut-off walls is disclosed. A drill rig assembly with double rotary heads drives a small diameter drill string and a much larger diameter drill string which is concentric with the smaller drill string and has a donut shaped drill bit configuration at the lower end thereof. Preferably, a steerable mud motor/drill is provided on one end of the small drill string and is guided to make as vertical a borehole as possible. In a preferred embodiment, the small inner drill is advanced to the full depth using the steerable mud motor/drill to achieve a high degree of verticality and a slight smaller casing is installed and used as a verticality guide for the much larger diameter outer drill string. In a further embodiment, the inner drill string is advanced a predetermined distance, then the outer string is advanced using the inner string as a verticality guide, these steps being repeated in alternating fashion to the final depth.

Abstract: An apparatus for use in a wellbore is provided that in one aspect includes: a drilling assembly configured to carry a first drill bit at an end thereof, a second drill bit disposed uphole of the first drill bit, and a connection device that is configured to selectively connect the second drill bit to the drilling assembly and disconnect the second drill bit from the drilling assembly.

Abstract: A drilling tool has a body with a main drilling region and a pilot drilling region, eccentric to the main drilling region. The main drilling region has main blades and the pilot drilling region has pilot blades. The main drilling region has a main pass-through diameter, centered upon a first axis, one of the main blades extending to the main pass-through diameter, the pilot region having a pilot gauge diameter, centered upon a second axis of rotation at least one of the pilot blades extending to the pilot gauge diameter, wherein part of a circle of diameter equal to the pilot gauge diameter and centered upon the second axis of rotation extends outside of a circle of diameter equal to the main pass-through diameter and centered upon the first axis.

Abstract: A reamer for subterranean wellbores may include a composite framework, which may include one or more high strength stems, each having one or more reamer bodies coupled thereto. The body may include a plurality of plates coupled together and may include additional components formed integrally therewith or coupled thereto. A method of forming a reaming tool may include forming a high strength stem and a reamer body and coupling the body to the stem. A method of using the reaming tool may include coupling one or more bodies in a drill string and reaming a wellbore.

Abstract: The present invention provides a global drilling system comprising a crown bit, a driver drill bit and a square drill bit. The crown bit has a tubular body with an inner surface and an outer surface, wherein the inner surface circumscribes a hollow passageway, and a pair of projections extending into said hollow passageway. The pair of projections are positioned substantially opposite one another on said inner surface. The driver drill bit has a drilling head with a pair of cut-away portions positioned substantially opposite one another and a pair of locking surfaces adapted for engaging the projections on the crown bit. The square drill bit has a drilling head with two tapered cut-away portions positioned substantially opposite one another. Each cut-away portion corresponds to one of the pair of projections such that the drilling head is able to pass through the hollow passageway of the crown bit.

Abstract: A hollow auger head assembly for penetrating geological formations that utilizes drill bit assemblies to which both blades and finger bits are attached. The method of securing the individual drill bit assemblies to the auger head reduces incidents of the drill bit assembly becoming detached from the auger head during drilling operations. Additionally, a rust-resistant attachment mechanism is used attach the drill bit assemblies to the auger head, which makes the drill bit assemblies easier to remove and replace. The configuration and arrangement of the bits improves cutting efficiency, increases wear life and reduces the likelihood of the bits breaking during operation.

Abstract: A novel drill bit includes a cutting reamer portion that cuts to gage diameter, and a pilot portion that cuts to a radius about 50%-80% of the reamer portion. The pilot portion extends downward from the reamer portion to create a distinct cutting area including pilot. The torque and weight on bit is evenly distributed between said pilot portion and said reamer portion of said drill bit by iterative adjustment of criteria such as backrake, siderake, cutter height, cutter size, and blade spacing.

Abstract: A sectional drive system for transmitting rotational power to an output, which system includes multiple splined drive segments which are nested and interlocked as a drive string that is rotatable in a selected straight or curved path. The top one of the drive segments cooperates with a drive mechanism to effect rotation of the nested drive segments in concert, and the bottom one of the drive segments connects to a suitable output such as a drill bit. Multiple, tapered and truncated exterior splines on each of the drive segments mesh with complementary interior splines on the adjacent drive segment to enable slight angular positioning of the drive segments on each other and facilitate dampening of drive vibration and bending of the drive string in or out of the chosen path in any desired direction as the drive string transmits rotational power in a curved path of desired magnitude from the drive mechanism to the output.

Abstract: A multi-purpose anchor bolt, which performs two principle functions: (1) it acts as an active reinforcement for the ground when it is installed and tensioned, and (2) it is used to excavate and advance the face in steps. The invention also includes the method of the multi-purpose anchor bolt's use. This invention is a hybrid of traditional and mechanized excavation techniques.

Abstract: A drill bit is provided for drilling holes in hard, reinforced material, including reinforced concrete. According to one aspect of the invention, wear-resistant inserts are provided in a cross-shaped pattern. The inserts ensure that the entire bottom surface of the drilled hole is engaged during each drill bit revolution. The inserts may be secured in pockets or slots. Fluid entry ports may be located between the inserts for efficient handling of drilling fluid and removal of drilled material, without impairing the structural integrity of the drill bit. According to another aspect of the invention, the drilling surface is separated into two or more stages to increase drilling efficiency, especially through composite material such as reinforced concrete.

Abstract: Although particular detailed embodiments of the apparatus and method have been described herein, it should be understood that the invention is not restricted to the details of the preferred embodiment. Many changes in design, composition, configuration and dimensions are possible without departing from the spirit and scope of the instant invention.

Abstract: An annular bit (1) having an attachable center drill (6) is proposed, in which annular bit (1), on the one hand, reliable holding of the center drill (6) in the annular bit (1) is ensured and, in particular, distributions of the cutting segments (3) on the annular bit (1) differing from the 90.degree. symmetry are made possible. This is achieved according to the invention in that the center-drill holder (4) has at least one push-in pin (11) and the wall of the annular bit (1) has at least one recess (14, 15, 16) for accommodating the push-in pin (11), which pin and recess are formed in such a way that the push-in pin (11) is retained in the recess (14, 15, 16) in the axial direction relative to the annular-bit axis in the locked state of the center-drill holder (4).

Abstract: A two trip sidetrack casing milling apparatus for elongating and enlarging a previously formed window in a cased borehole in preparation for a subsequent sidetracking drilling operation is disclosed. The apparatus consists of three mills on a shaft, a first window mill is secured to an end of a shaft. The first window mill forms a diameter larger than a diameter of a subsequent sidetracking drill bit that is passed through the window. A second pilot mill is secured to the shaft and strategically positioned above the first window mill. The second pilot mill forms a diameter that is less than the diameter of the first window mill. A third watermelon mill is secured to the shaft and strategically positioned above the second pilot mill. The third watermelon mill forms a diameter that is at least the same diameter as the first window mill.

Abstract: An auger is provided with a boring head having an arrangement for cutting relatively hard earth formations such as rock. First and second groups of drill bits are mounted to the boring head such that when the head is rotated, each bit in those groups cuts a different path at a different height to provide more than 100% coverage of the work surface being cut, while stabilizing the auger by distributing the down force of the auger over the entire work surface. The drill bits also are orientated to ensure bit rotation at relatively large attack angles (the angle the bit forms with the work surface therebeneath) of about 50.degree.-60.degree. to enhance auger penetration rates without detracting from the bit sharpening effect that results from proper bit rotation.

Abstract: An auger is provided with a boring head having an arrangement for cutting relatively hard earth formations such as rock. First and second groups of drill bits are mounted to the boring head such that when the head is rotated, each bit in those groups cuts a different path at a different height to provide more than 100% coverage of the work surface being cut, while stabilizing the auger by distributing the down force of the auger over the entire work surface. The drill bits also are orientated to ensure bit rotation at relatively large attack angles (the angle the bit forms with the work surface therebeneath) of about 50.degree.-60.degree. to enhance auger penetration rates without detracting from the bit sharpening effect that results from proper bit rotation.

Abstract: Disclosed are methods for applying durable markings to wearing surfaces, such as concrete factory floors, roadways, terrazzo or ceramic tile floors, or for imparting particular floor surface qualities, such as providing a non-skid surface. A diamond surface drill bit rotating at, for example, 2500 to 5000 rpm is employed to form dry recesses in the surface, which recess is immediately receptive to adhesive for attaching a premolded insert, or to an insert formed in situ, such as an insert of an acrylic polymer. The disclosed surface drill bit has a cutting end with two general types of diamond-impregnated cutting element segments attached. Attached around the periphery of the cutting end are peripheral gauge cutting element segments of arcuate configuration spaced from each other.

Abstract: A process for protecting nonstable or moderately stable, cohesionless to slightly cohesive geologic formations, in particular, in tunnel construction, in which drill holes are first made by boring into the formation and, following completion of the boring, the drilling rod is removed. During this removal a hardenable injection material is forced into the drill hole, whereby, using a drilling rod, a pointed rod or anchoring element is placed in position in the boring. This element remains in the boring during removal of the drilling rod, and is solidly connected to the formation by the injection material.

Abstract: An ice auger includes a pair of ice boring blades fixedly attached to the bottom of a straight inner auger drive bar. A brace and bit arrangement at the top of the drive bar is for rotating the drive bar and either forcing it down toward the ice to bore a cylindrical hole of predetermined diameter through the ice or to force it up away from the ice after the hole has been bored to ream out a portion of that hole to form an inverted funnel shape opening. A tubular outer sleeve surrounds the drive bar and is movable between an upper boring condition and a lower reaming condition with respect to the drive bar. Two slotted longitudinally extending ice reaming blades are pivotally mounted at their top portions to the ream control sleeve. A reaming blade camming support bar attached to a bottom portion of the drive bar carries camming pins slidable in the reaming blade slots.

Abstract: A directional drill attached to a drill string having periodic concentric collars is advanced in an inverted arcuate path to form a pilot hole underneath an obstacle followed by a larger concentric washover pipe. When the washover pipe reaches the surface on the other side of the obstacle a first reamer is attached to the end of the washover pipe exiting the drilling path, a second reamer of smaller diameter than the first reamer is attached to the other end of the first reamer by means providing for some separation between the two reamers, and a production casing of smaller diameter than the second reamer is attached to the other end of the second reamer with a swivel. The remaining length of the first portion of casing is supported some distance above the ground on rollers located above and beyond the exit point of the pilot hole. The reamers are operated by rotating the washover pipe and simultaneously drawing the washover pipe through the pilot hole.

Abstract: A device is provided for creating recesses for road surface markers in road surfaces which makes initially a cut sufficient to stabilize the device in the desired position and then fragments and discharges core material within a circular cut defining the recess. Such fragmentation is effected by rotation of a plurality of radially disposed cutting edges each spanning only a portion of the radius of the material to be fragmented.

Abstract: A directional drill attached to a drill string having periodic concentric collars is advanced in an inverted arcuate path to form a pilot hole underneath an obstacle followed by a larger concentric washover pipe. When the washover pipe reaches the surface on the other side of the obstacle a first reamer is attached to the end of the washover pipe exiting the drilling path, a second reamer of smaller diameter than the first reamer is attached to the other end of the first reamer by means providing for some separation between the two reamers, and a production casing of smaller diameter than the second reamer is attached to the other end of the second reamer with a swivel. The remaining length of the first portion of casing is supported some distance above the ground on rollers located above and beyond the exit point of the pilot hole. The reamers are operated by rotating the washover pipe and simultaneously drawing the washover pipe through the pilot hole.