Abstract: A Kelly bar apparatus includes a plurality of concentric tubes in a telescoping arrangement having either a locking feature provided by a series of keys and notches that interlock selectively, or one or more blocking tabs that prevent complete telescopic extension of at least one of the tubes when the tubes and associated keys are in an unlocked position, or both. Related subterranean bore drilling systems and drilling methods are also described.

Abstract: A coiled tube injection drive assembly having a pair of opposed, upwardly extending movable carriages positioned in opposed fashion so that portions of tubing may be vertically disposed and engaged between the movable carriages, each of the movable carriages comprising a respective gripper chain and associated bearing chain assembly, where the bearing chain is mounted on sprockets that are coaxially disposed between spaced apart gripper chain sprocket wheels so that the bearing sprockets are mounted about the same shafts as the gripper chain sprockets, without being directly mounted to rotate with those shafts. Other assembly features and related methods are also described.

Abstract: An injector for flexible tubing has endless drive conveyors on opposite sides of a pathway for the tubing. The drive conveyors include gripper blocks that work in opposing pairs along the tubing pathway. The pairs of gripper blocks are clamped to the tubing and moved along the tubing pathway to either inject the tubing into a well or withdraw the tubing from a well. The gripper blocks are clamped to the tubing by way of skates, which work in opposing pairs. The skates have rollers, with rollers contacting the gripper blocks. Each roller has two ends, which ends are received by bearings inside of mounts on the respective skate.