Abstract:
A drill rod changer assembly for a drill rig includes an elongated support shaft (5) having a housing (20, 30) at each end for retaining ends of drill rods, the support shaft being adapted for removable attachment to a drill rig structure (3), a carousel-type drill rod spacer (120) on the shaft and a pair of gripper arms (70, 74) adapted for removable attachment to a drill rig structure at spaced apart positions adjacent each end of the support shaft. A hydraulic actuation device (40) rotates the support shaft and carousel drill rod spacer between a rod storage position and a rod usage position. Each gripper arm is moved between the drill rod storage and usage positions by hydraulic actuation devices on each arm. Each gripper arm carries a sliding gate member that opens and closes the housings in response to movement of the gripper arm. The support shaft, and each gripper arm assembly being supplied as modularized assemblies that can be individually attached and removed from a drill rig to expeditiously change between various lengths of drill rod.
Abstract:
A removable guide member for guiding drill string components in a drill hole includes an elongated body having a centerline axis with a bore extending along the axis. The body terminates in a head end having a preselected radial dimension with respect to the centerline axis. The guide member is adapted to be threadably connected to adjoining drill string components. The head end radial dimension is preselected to space an outer surface thereof in close proximity to a drill hole sidewall, so that if the drill string begins to deviate out of alignment, the outer surface of the head end will contact the drill hole sidewall to stabilize alignment. The guide member can be inserted into any position along the drill string.
Abstract:
A drill rod has a first and second threaded end. The threads on the two ends have a different thread pitch so as to provide a different degree of joint tightness (torque) when the ends are threaded into a matching coupling. The different degree of joint tightness at each rod end causes a breaking of the joint connection in a predictable sequence, thereby facilitating drill string removal from a drill hole. An alternate embodiment achieves a different degree of joint tightness by having different thread lengths at each end of the drill rod and coupling, instead of different thread pitches.