A reamer for drill string pullback of a horizontal directional drill includes a shaft portion defining a central axis and a first end configured for attachment with a drill string of the horizontal directional drill. A plurality of vanes extend radially from an outer periphery of the shaft, each of the plurality of vanes defining an outer peripheral tooth base surface. On each of the plurality of vanes, a plurality of cutter teeth are individually and removably secured along the outer peripheral tooth base surface thereof, each one of the plurality of cutter teeth including a body and a PDC insert manufactured separately from the body and joined therewith. Each cutter tooth of the plurality is coupled to the respective one of the plurality of vanes by a removable fastener extending at least partially through the cutter tooth and at least partially through the one of the plurality of vanes.

An apparatus for feeding a tubular object inside a drill hole, a rock drilling rig and a method of supporting mouth openings of drill holes is provided. The apparatus includes a support device for supporting an elongated tube element blank having the potential for several successive tube inserts. A front end of the tube element blank is moved longitudinally inside a drill hole by means of a feeding device. Thereby, the drill hole is provided with a protective section extending a limited longitudinal dimension towards a bottom of the drill hole. The apparatus further includes a separation device for detaching the mentioned tube inserts one by one from the tube element blank.

An apparatus for feeding a tubular object inside a drill hole, a rock drilling rig and a method of supporting mouth openings of drill holes is provided. The apparatus includes a support device for supporting an elongated tube element blank having the potential for several successive tube inserts. A front end of the tube element blank is moved longitudinally inside a drill hole by means of a feeding device. Thereby, the drill hole is provided with a protective section extending a limited longitudinal dimension towards a bottom of the drill hole. The apparatus further includes a separation device for detaching the mentioned tube inserts one by one from the tube element blank.

A nested drill bit assembly is disclosed for drilling a wellbore, comprising a parent bit and at least one child bit nested within the parent bit. Each bit in the nested drill bit assembly may be driven by a respective casing that gets cemented in place as part of a drilling with casing system. The parent bit and child bit(s) may be rotated together, with the parent bit and child bit collectively defining a contiguous cutting profile for drilling an initial segment of the wellbore. A driver is then lowered into the casing for connection to the child bit to drill beyond the parent bit. The driver may be configured as a drive bit for drilling through material leftover from a cementing operation prior to connecting to the child bit.

A nested drill bit assembly is disclosed for drilling a wellbore, comprising a parent bit and at least one child bit nested within the parent bit. Each bit in the nested drill bit assembly may be driven by a respective casing that gets cemented in place as part of a drilling with casing system. The parent bit and child bit(s) may be rotated together, with the parent bit and child bit collectively defining a contiguous cutting profile for drilling an initial segment of the wellbore. A driver is then lowered into the casing for connection to the child bit to drill beyond the parent bit. The driver may be configured as a drive bit for drilling through material leftover from a cementing operation prior to connecting to the child bit.

A directional casing drilling system includes a casing string, a drilling rig and a retrievable Bottom Hole Assembly (BHA). The drilling rig includes a casing drive for rotating the casing string in the borehole, a control system for controlling the casing drive, and a mud pump for pumping a continuous flow of drilling mud into the casing string. The BHA includes a torque transfer section, with which it is secured in the casing string, and a drill bit section held in a drilling position in the torque transfer section. It further includes a mud drive that rotates the drilling position of the drill bit section about the longitudinal axis of the torque transfer section, and a communicating device for communicating the orientation of the drill bit to the control system. The BHA is steered by adjusting the rotational speed of the casing string.

A rupture disc assembly and a float tool incorporating the rupture disc assembly is disclosed. The rupture disc assembly may include a rupture disc assembly comprising a rupture disc, an upper tubular portion and a lower tubular portion, and a securing mechanism for holding the rupture disc between the upper and lower tubular portions. A float tool for creating a buoyant chamber in a casing string may include the rupture disc assembly and a sealing device for sealing the lower end of the casing string, the buoyant, sealed chamber may be created there between. In operation, applied fluid pressure causes the rupture disc to move downward. The rupture disc may be shattered by contact with a surface on the lower tubular portion. Full casing internal diameter may be restored in the region where the rupture disc formerly sealed the casing.

A rupture disc assembly and a float tool incorporating the rupture disc assembly is disclosed. The rupture disc assembly may include a rupture disc assembly comprising a rupture disc, an upper tubular portion and a lower tubular portion, and a securing mechanism for holding the rupture disc between the upper and lower tubular portions. A float tool for creating a buoyant chamber in a casing string may include the rupture disc assembly and a sealing device for sealing the lower end of the casing string, the buoyant, sealed chamber may be created there between. In operation, applied fluid pressure causes the rupture disc to move downward. The rupture disc may be shattered by contact with a surface on the lower tubular portion. Full casing internal diameter may be restored in the region where the rupture disc formerly sealed the casing.

A rotary drill bit for use with a horizontal directional drill string. A coupler at a proximal axial end is configured to attach the rotary drill bit to a drill head at a distal end of the drill string. A cutting portion at a distal axial end is provided with a plurality of vanes with respective cutters that operate to cut a hole in earth when the rotary drill bit is rotated about a central axis. The plurality of vanes project radially outwardly from a surface of the cutting portion such that the surface forms respective troughs circumferentially interspersed with the plurality of vanes. A plurality of engagement features is positioned axially within the cutting portion and radially inward of an outer cutting diameter to facilitate attachment of a product pullback device between the plurality of vanes without removing the rotary drill bit, or any portion thereof, from the drill head.

Method for installing a geothermal system, comprising: arranging a drilling equipment, including a support structure and a terminal module, mounted on the support structure; by means of the drilling equipment, drilling the soil in succession along a substantially vertical first tract, a substantially horizontal second tract and a substantially vertical third tract, the first, second and third tracts forming a substantially U-shaped well, the first tract having a surface inlet, where the drilling is started, the third tract having a surface outlet, where the drilling is finished, the well crossing a geothermal zone; arranging a casing in the well, so that the casing extends between the inlet of the first tract and the outlet of the third tract; arranging a heat utilization system, associated with an axial end of the casing; arranging a hydraulic system configured to cause a heat transfer fluid to circulate in the casing, so that the heat transfer fluid will absorb heat from the geothermal formation and will release it at the heat utilization system.