A drilling machine is mounted on a slide which is movable along a feed beam. The drilling machine is connected to the slide by means of a hinge which is situated farther from the feed beam than the drill axis defined by the drilling machine. Furthermore an elastic element has been provided between the drilling machine and the slide, the stiffness of the elastic element being such that the direction of the drill axis is independent of the applied feed force.
Telescopic columns for making foundations including in reciprocal coordination and cooperation a motor group comprising at least two guide pulleys having a proportion to each other of one to two; inner and outer movable columns; axially immovable canoe guide means surrounding said columns; a chain secured to the two ends of the outer movable column and driven by the smaller of said pulleys; a chain secured to the lower part of the inner movable column and to the upper part of the axially immovable guide canoe means and driven by the larger pulley; a cable connecting the upper part of the inner movable column to the lower part of the axially immovable guide canoe means and a transmission sheave solidly fixed to the lower part of the outer movable column through which passes said cable.
Apparatus for manipulating equipment by selectively holding it in a gripping device mounted on a movable closed-loop belt. In the particular embodiment shown, a swivel and elevator combination is mounted on a brace which runs along a track in the derrick of a well workover rig. A belt chain is joined to the brace to form a closed loop, and is motor-driven to raise or lower the swivel and elevator arrangement to move drill pipe or casing into or out of a well.
