A tool for extracting well pipe casings resembles an enlarged pipe-thread tap. The tool is designed to be suspended under and driven by the traveling rotary table and hydraulic vertical drive system of a conventional drilling rig. By this means, well pipe casings are withdrawn from wells by engaging the tops of such well pipe casings, and unlike the prior art, which grapples well pipe casings at their very bottom, and at the end of a cable. Unlike withdrawing casing by a cable pull, wherein cables stretch and unstuck casings might launch like projectiles, the extractor tool manages to withdraw well pipe casing in a recoilless manner, which is more controlled, and safer.
Accessories And Method For Hollow Stem Auger Retraction
Withdrawing a hollow stem auger string from a well includes a retractor having C-shaped inter-coil insertions and a hoist having tong-arms, one which terminates in an inwardly disposed pin. The retractor connects to a drilling rig's hydraulic cylinder vertical drive system, the hoist to a winch system thereof. The retractor engages the string by the C-shaped inter-coil insertion disposed between one coil of the helical flight of the topmost section of the string. The hoist engaged the top collar of the topmost section by the at least one pin inserting into a pin hole thereof. The string is lifted about the height of one section by the retractor, which is promptly disengaged. The topmost section is detached, and carried by the hoist to elsewhere to be dropped. The method repeats by re-engaging the retractor and hoist and then returning to the activity of lifting.
A flute-wiping auger cleaner has a laterally-shearing shackle, an axial track spaced parallel to the auger; and a traveling carriage on the track for supporting the shackle. The shackle includes a series of angularly-staged wiper blades to project into the flute of the auger and centrally stabilize the blades on the turning axis of the auger. The shackle is biased not only to pressure the wipers inwards towards the auger's cylindrical sidewall but also allow the shackle to open slightly against the force of the bias in event a blade cannot dislodge a difficult clump of fouling material in the flute. In that event, the blade is pushed out and then pressured back in as it rides over the difficult-to-dislodge clump. Spinning the auger causes the blades to travel the length of the helical flute while the shackle travels axially on the track.