A system and method for installing casing in a blind horizontal well for blind horizontal directional borings. The system and method may include an example of an offset transmitter sonde assembly that contains an open central passage through which well casing can be inserted, and an example of a drill bit assembly that may be remotely uncoupled from a drill string, leaving the bit in the bore created. Remote uncoupling of the drill bit assembly tends to allow a casing to be installed in the bore while the drill string and bit remain in the bore for support during casing installation. After installation of the casing the drill bit assembly may be uncoupled from the drill string, allowing the drill string to be withdrawn from the bore, with the drill bit assembly remaining in the bore.

An arrangement at a drill includes a drill bit intended to be inserted at its neck into a chuck in a down-the-hole drill, a control means for guiding the drill and a lining pipe, a coupling arrangement in the form of a bayonet coupling or similar with which the drill can be coupled to the control means in a manner that allows them to be separated and that in its freed condition allows the drill, together with the down-the-hole drill, to be withdrawn through the lining pipe, a flushing passage for the supply of flushing agent in front of the drill and an evacuation passage for the removal of drilling cuttings together the flushing agent. It also includes a casing shoe that can be applied at the forward end of the lining pipe and a contact surface arranged at a stationary part of the down-the-hole drill.

An arrangement at a drill includes a drill bit intended to be inserted at its neck into a chuck in a down-the-hole drill, a control means for guiding the drill and a lining pipe, a coupling arrangement in the form of a bayonet coupling or similar with which the drill can be coupled to the control means in a manner that allows them to be separated and that in its freed condition allows the drill, together with the down-the-hole drill, to be withdrawn through the lining pipe, a flushing passage for the supply of flushing agent in front of the drill and an evacuation passage for the removal of drilling cuttings together the flushing agent. It also includes a casing shoe that can be applied at the forward end of the lining pipe and a contact surface arranged at a stationary part of the down-the-hole drill.

A drilling device for a down-the-hole drilling apparatus. The drilling device includes in a guide, a drilling member and a flushing mechanism configured to flush drilling waste. The drilling mechanism includes first and second drilling bit arrangements that are movable with respect to the drilling device and that are arranged to be expanded to drill a hole having a greater cross-sectional surface area than an end of the casing and arranged to be reduced to a size smaller than the end of the casing. Bit pieces of the second drill bit arrangement expand and reduce the second drill bit arrangement. The bit pieces expand the second drill bit arrangement by moving in a radial direction outwards in slide grooves, by rotating the guide in a drilling direction, and move in the radial direction inwards in the slide grooves, by rotating the guide in an opposite direction.

The present application discloses the use of the pre-stressed steel strand in the procedure of multi-angle core drilling. Using the properties of high strength and toughness of pre-stressed steel strand material, the core internal pipe is pushed inside the drill rod without deformation and damage. The rolling wheel is designed to rapidly take out and put back the pre-stressed steel strand to finish the extracting of the core, without taking out and putting back the drill rod. Without altering the original structure of the drilling machine, the technology of 360 core drilling is realized. Problems of tedious and arduous operations and a low efficiency in multi-angle drilling are resolved completely. The use of the pre-stressed steel strand not only can significantly improve the drilling-in efficiency, but also is beneficial to guarantee the quality of the rock mineral coring, reduce the cost of drilling, lower the labor intensity notably.

A system and method for installing casing in a blind horizontal well for blind horizontal directional borings. The system and method may include an example of an offset transmitter sonde assembly that contains an open central passage through which well casing can be inserted, and an example of a drill bit assembly that may be remotely uncoupled from a drill string, leaving the bit in the bore created. Remote uncoupling of the drill bit assembly tends to allow a casing to be installed in the bore while the drill string and bit remain in the bore for support during casing installation. After installation of the casing the drill bit assembly may be uncoupled from the drill string, allowing the drill string to be withdrawn from the bore, with the drill bit assembly remaining in the bore.

A drill unit for forming a column in ground which includes an outer drill and a concentric inner drill, where attached to the outer drill there is at least one drill tooth which includes a first face, a second face and a base face wherein:the first face and the second face are immediately adjacent one another and are coterminous at a first edge and a second edge;the base face is the face closest to, or coterminous with, the first terminal end;all faces, except the base face, are independently coterminous with the base face; and extend away from the base face in the same direction;at least part of the at least one drill tooth extends away from the first terminal end to terminate at the second edge;the second edge is the edge of the at least one tooth that is most longitudinally distant from the first terminal end;the first face further includes a first alpha edge, where the first alpha edge is an edge of the first face opposite the first edge;a line joining the first edge and the first alpha edge, where the first face and the base face are coterminous, a first face alignment line, is at an angle of to a perpendicular extending from the first outside surface;the second face further includes a second alpha edge which is an edge of the second face opposite the first edge; anda line joining the first edge and the second alpha edge, where the second face and the base face are coterminous, a second face alignment line, is at an angle of to a tangent on the first outside surface; such that, when in use forming the column, the first edge is configured to be a leading edge.

A down-the-hole drilling device, being meant for drilling a hole with and a casing part is described. The drilling device comprises in its drilling head: a drilling arrangement, having first drilling means for drilling a center hole and second drilling means for reaming the center hole for the casing part; and a flushing flow arrangement for feeding of a flushing medium onto a drilling surface of the drilling arrangement by one or more feed channels and for discharging the same from the drilling surface together with drilling waste. The casing part is arranged to be pulled into the hole to be drilled by power influence directed thereto from the drilling arrangement. A feed channel of the flushing flow arrangement at least partly ends up on the drilling surface at a flushing channel that exists in the longitudinal direction of the drilling device essentially behind a rearmost part of the drilling surface of at least of the first drilling means. The flushing flow arrangement comprises on the bottom of the flushing channel a supplementary flushing groove that extends from the feed channel towards the outer periphery of the drilling arrangement.

The inner bit is provided with: a supply hole which is open at the distal end portion of the inner bit; and a discharge groove which is formed in an outer peripheral surface of the inner bit and extends in the direction of the axial line. The supply hole is provided with: a distal end blow hole which is open in a distal end surface of the distal end portion of the inner bit; and an outer peripheral blow hole which is open in an outer peripheral surface of the distal end portion of the inner bit. An outer peripheral groove via which the outer peripheral blow hole communicates with the discharge groove is formed in the outer peripheral surface of the inner bit. The outer peripheral groove is covered with the ring bit from the outside in a radial direction.

The inner bit is provided with: a supply hole which is open at the distal end portion of the inner bit; and a discharge groove which is formed in an outer peripheral surface of the inner bit and extends in the direction of the axial line. The supply hole is provided with: a distal end blow hole which is open in a distal end surface of the distal end portion of the inner bit; and an outer peripheral blow hole which is open in an outer peripheral surface of the distal end portion of the inner bit. An outer peripheral groove via which the outer peripheral blow hole communicates with the discharge groove is formed in the outer peripheral surface of the inner bit. The outer peripheral groove is covered with the ring bit from the outside in a radial direction.