THREADED TOOL JOINT WITH DUAL MATING SHOULDERS

摘要

A tool joint for use in connecting sections of pipe string for use in drilling. The joint is a pin (10) and box (11) connection of the type used in oil well tubing, casing, and the like. The driveable threaded joint has dual mating shoulders (19, 21) and nose faces (18, 20) on the pin and box members (10, 11). The connection is designed so that compressive loads on the pin and box members (10, 11) are transferred substantially through the pin and box shoulders (19, 21) rather than through the thread form (16, 17). The dual mating shoulders (19, 21) substantially improve the joint's ability to withstand the intense axial compression loading that occurs when driving the pipe into the ground.