Abstract: The present invention relates to a wireline retrieval head assembly and downhole tool, the wireline retrieval head assembly for coupling to the downhole tool for installation in and retrieval from downhole in a mineral industry field of use, wherein a first of the wireline retrieval head assembly and downhole tool has a retention member that has or is configured to receive a pivot member and a second of the wireline retrieval head assembly and downhole tool has a complementary link with an opening for receiving the pivot member, such that the link can be coupled to the retention member to create a pivot coupling to allow for articulation between the wireline retrieval head assembly and the downhole tool during installation and retrieval of the downhole tool, and the link can be removed from the retention member to remove the downhole tool from the wireline retrieval head assembly.

Abstract: The invention provides a downhole apparatus and method of use. The apparatus comprises a plurality of elements assembled together to form a ring structure oriented in a plane around a longitudinal axis and a drive mechanism for effecting rotation of the ring structure with respect to a wellbore or subterranean formation. The ring structure is operable to be moved between a collapsed condition and a first expanded condition by movement of the plurality of elements, and the ring structure comprises one or more surfaces or formations for cutting and/or removal of material from the wellbore or subterranean formation.

Abstract: A coring bit for use on a coring tool for extracting a sample of subterranean formation from a wellbore includes a bit body having a cavity, wherein a throat portion of the cavity extends into the bit body from a face of the bit body. The coring bit includes a sleeve disposed within the cavity of the bit body, the sleeve configured to separate a face discharge channel and a throat discharge channel. The face discharge channel is located radially outward of the sleeve and the throat discharge channel is located radially inward of the sleeve. A method of repairing a such a coring bit includes removing the sleeve from the cavity of a bit body.

Abstract: In an aspect, an apparatus for use in a wellbore includes a tubular and a drilling assembly configured to carry a drill bit at an end thereof, wherein the drilling assembly is configured to be positioned within the tubular, wherein the tubular and drilling assembly are configured to be run in the wellbore together. The apparatus also includes an actuation device in the tubular configured to selectively extend the drilling assembly from and retract the drilling assembly into the tubular.

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: A drill bit comprises a bit body connectable to a drill string at an first end, which bit body is provided with a longitudinal passageway extending from an opening at the first end to a port at a second end. The drill bit further comprises a closure element for closing the passageway, and when the closure element is in a closing position, the closure element is removable. Further, the closure element comprises a first and a second member that are movable relative to each other between an expanded configuration and a collapsed configuration, in which collapsed configuration, the closure element is retractable through the passageway to the first end.

Abstract: A reaming tool for enlarging an earth bore in a subsurface formation in which a sub is connected to a lower end of a drill string and elongated cutter blades are pivotally secured to a lower end of the body which have cutter elements preferably in the form of rotatable cutter disks along their leading edges and a fluid delivery hose leads into fluid passages in each of the cutter blades to supply fluid under pressure to a series of fluid discharge nozzles associated with the cutter elements.

Abstract: A drill bit assembly for earth boring operations in which a sub is connected to a lower end of a drill string and elongated cutter blades are pivotally secured to a lower end of the body which have cutter elements preferably in the form of rotatable cutter disks along their leading edges and a fluid delivery hose leads into fluid passages in each of the cutter blades to supply fluid under pressure to a series of fluid discharge nozzles associated with the cutter disks.

Abstract: In a retrievable drill bit assembly, a standard drill pipe or casing pipe has a sub threaded into its lower end which forms a seat coupling for upper rounded pivotal ends of a pair of drill bits which are pivotally mounted between a pair of lift plates. The drill bits have blades extending from the pivotal ends with hardened cutter elements in staggered relation along or adjacent to the leading edge and a fluid passage leading into a series of nozzles in the blades which together with the rotational force of the drill pipe and the frictional force of the blades on the material to be bored will cause the blades to assume and maintain a mutually perpendicular position. The blades or cutters can be retrieved by a retrieval apparatus for the purpose of removal and replacement with a new set of blades.

Abstract: A down hole running tool 14 travels in a first direction through a drill pipe for installing bit segments 18 at the end of a drive sub 12 attached to the drill pipe. The tool 14 includes a first portion 82 and a second portion 84 which is retractably coupled to a leading end of the first portion 82. The first portion 82 includes a tubular extension 134 which receives a spigot 136 that extends from an upper end of the second portion 84. A pin 138 extends transversely through the tubular extension 134 and resides within opposing slots 140 formed in the spigot 136. There is a stepped reduction in the internal diameter at the lower end of the tubular extension 134 so as to form a cup-like structure 146. A spring 168 is disposed about the spigot 136 and has an upper end seated in the cup-like structure 146 and a lower end bearing against an upper face 170 of the second portion 84. The spring 168 is biased so as to push the first and second portions 82 and 84 apart in the longitudinal direction.

Abstract: A retraction system allows disengagement of retrieval latch dogs of a down hole running tool from a bit locking sleeve. The locking sleeve is slidably retained within a drive sub and includes a pair of slots which are engaged by the retrieval latch dogs when the tool is used to retrieve bit segments from the drive sub. The retraction system includes a sleeve which is slidably mounted on a main body of the tool and spring which is biased to push the sleeve over the retrieval latch dogs. The sleeve has a pair of diametrically opposed slots through which the retrieval latch dogs can extend for contacting the inner surface of the drive sub. The retraction system also includes a length of the inner surface of the drive sub which is made of progressively reducing diameter in the direction of retraction of the tool from the drive sub. The upper end of each slot is provided with a bevel for directing the retrieval latch dogs in the inward direction.

Abstract: A method to drill a hole in the soil by a bit assembly and a bit assembly comprising a ring-shaped bit (2) to drill the outer circle of the hole and to which a protection tube system (4), mounted in the hole while drilling, is coupled, and a cylindric inner bit (1) to drill the center portion of the hole, from which bit at least the rotative motion is transmitted to the outer bit (2). Drilling by the outer bit (2) and pulling out the protection tube (4) are disconnected upon need by reverse rotation of the inner bit, whereafter drilling is continued with the inner bit (1) only.

Abstract: Extendable bit teeth are supported by the guide grooves formed on the end face at the point of a bit body in such a manner as to be slidable. The extendable bit teeth slide along the guide grooves in an excavating direction to thereby project from the end face at the point of the bit body. The extendable bit teeth slide in an opposite direction to the excavating direction to project from the outer periphery of the point of the bit body. Since the extendable bit teeth are pressed against the ground during excavation, the extendable bit teeth projects from the outer periphery of the point of the bit body so that the bit gauge can be extended, and most of the excavation hole is excavated by the bit body.

Abstract: An insert for releasably retaining drill bit segments in a ground drill takes the form of a cylindrical tube movable within the ground drill between an installation position and a retrieval position. A pair of opposing tapered peaks extends from the upstream end of the insert. Sides of the peaks slope sharply in a downstream direction and lead to flats separating the peaks. When a running tool with radially extending latch dogs travels down the drill, the latch dogs contact the peaks to cause the tool to rotate about its longitudinal axis. When the latch dogs hit the flats they engage the insert, pushing it down into the installation position and locking the bit segments into a cutting position. Another set of latch dogs provided on the tool can engage slots formed in the insert to pull the insert upwardly and release the bit segments.

Abstract: A retractable drill bit system 10 comprises a drive sub 18 which is adapted for connection to a lower end of a drill 12, a tool 20 for installing and retracting drill bit segments 22 from the drive sub 18; and an insert 24 for selectively locking the bit segments 22 to an end of the drive sub 18 and releasing the bit segments 22.A plurality of recesses 5B are formed about an inner circumferential wall at one end of the drive sub 18 and a landing seat 32 formed about the inner wall upstream of the recesses 58. The area of the interior wall between the landing seat 32 and recesses 58 is profiled with a series of tapered and level surfaces.The tool 20 includes a slidable cradle 176 extending from one end about which the bit segments 22 are held during installation and retrieval. The bit segments 22 being held in place about the cradle by an elastic band 198.

Abstract: A wellbore is formed in the earth with an elongated, non-rotating tubular drillstem which may consist of a well casing or liner and including an expendable sub and reamer bit part connected to the lower distal end of the drillstem. A retrievable drilling fluid operated motor and drive member assembly are disposed in the drillstem. The motor and drive member include pressure fluid responsive mechanism for engagement with and disengagement from the reamer bit part to rotatably drive the reamer bit part and a central bit part connected to the drive member without rotating the casing type drillstem. The motor, drive member and central bit part may be retracted from the drillstem upon completion of drilling operations without retrieving the expendable reamer bit part.

Abstract: Wellbores are formed in the earth with elongated, tubular drillstems which include retrievable bit and drive motor assemblies. The retrievable bit assembly includes a body having locking dogs engageable with cooperating recesses formed in a sub at the bottom of the drillstem. The bit assembly includes radially extendable and retractable arms with cutters thereon for forming the wellbore to a diameter greater than the drillstem, but whereby the arms may be retracted to withdraw the bit assembly through the drillstem with wireline retrieval apparatus or the like. The wellbore may be drilled with a tubular drillstem comprising wellbore casing with a retrievable bit and motor assembly connected to the lower end of the drillstem and retrievable through the drillstem by the wireline retrieval apparatus whereby the casing may be left in the wellbore upon completion of drilling operations.

Abstract: The present invention comprises a method and apparatus for simultaneously drilling and casing a wellbore. More specifically, the apparatus comprises an outer conduit string containing an inner drill string carrying a bit capable of drilling a wellbore of greater diameter than the outer string. The drill string may be adapted to drill a nonlinear wellbore by offsetting the drill bit from the longitudinal axis of the outer string, and the drill bit is preferably retractable to permit withdrawal of the drill string after the wellbore is completed, leaving the outer string of casing or liner in place. The wellbore is drilled by rotating the drill bit and advancing the drill string by pushing from the surface, and the outer string is advanced by being pulled along by the drill string.

Abstract: The present invention comprises a method and apparatus for simultaneously drilling and casing a wellbore. More specifically, the apparatus comprises and outer conduit string containing an inner drill string carrying a bit capable of drilling a wellbore of greater diameter than the outer string. The drill string may be adapted to drill a nonlinear wellbore by offsetting the drill bit from the longitudinal axis of the outer string, and the drill bit is preferably retractable to permit withdrawal of the drill string after the wellbore is completed, leaving the outer string of casing or liner in place. The wellbore is drilled by rotating the drill bit and advancing the drill string by pushing from the surface, and the outer string is advanced by being pulled along by the drill string.

Abstract: A drill bit for core boring of the type provided with a multi-layered bit head, so constructed that when the blades of the upper-layered bit head have become worn out, it is possible to easily withdraw them without removing the bit from the bore. The core boring operation is then continued without delay by using the blades of the newly exposed lower-layered bit head. The drill bit is also so constructed that it is possible to eliminate any displacement of the upper layer blades from their fitted position on the blades of the lower layer blades during drilling by using the upper layer blades and at the same time, it is possible to easily disengage the engagement between the bit body and the upper layer blades when the upper layer blades have become worn out.