Abstract: A threaded casing connection for use in drilling-with-casing operations includes an integral, sacrificial wear sleeve on the downhole end of the coupling which has additional wear protection on portions of its outer wall and leading face.

Abstract: A modified API Buttress threaded casing connection is disclosed for use in drilling oil and gas wells in lieu of using conventional drill pipe. The coupling threads only are multiple tapered yet can be mated with standard API Buttress pin threads having a single taper. The coupling is also shortened to permit abutment of the mating pins at the center of the coupling and can be further enhanced with an integral, sacrificial wear sleeve on one end of the coupling.

Abstract: A modified API Buttress threaded casing connection is disclosed for use in drilling oil and gas wells in lieu of using conventional drill pipe. The coupling threads only are multiple tapered yet can be mated with standard API Buttress pin threads having a single taper. The coupling is also shortened to permit abutment of the mating pins at the center of the coupling and can be further enhanced with an integral, sacrificial wear sleeve on one end of the coupling.

Abstract: Threaded oil well pipe joint comprising a coupling having internally threaded ends and an intermediate unthreaded area with substantially greater cross section area. The internally threaded ends are made up with externally threaded ends of pipe. Stresses resulting from joining either end of the coupling to a pipe section are absorbed by the intermediate area so that such stresses will not affect the opposing end of the coupling. Because the stresses during makeup of one end do not affect the other end of the coupling, the overall stress levels, pootential for thread damage and leakage are reduced in the joint. As a result, the outside diameter of the coupling may be significantly reduced so that the joint can be run more easily in a restricted diameter well bore.

Abstract: A box end casing connector is disclosed for use in connecting a string of casing sections for use in oil and gas drilling operations. The box connector is provided with an inside surface conventionally threaded with API standard threads and adapted to receive a pin member with mating threads. The pin member utilized is the threaded end of a subsequent casing section. The box connector is adapted to be integrally welded to the casing section and is further provided with a tapered shoulder and an externally beveled face to facilitate movement of the casing connector into and out of the bore of a restricted diameter blowout preventer.