Abstract: An apparatus and method are provided for enhancing fatigue and stress resistance properties of a subterranean well drill pipe string section by providing a helical groove near the pipe to tool joint weld. Stresses in and around the top portion of the pipe are redistributed to and absorbed by the helical groove region of the drill pipe string section, which has a relatively greater resistance to fatigue caused by bending and other stresses, thereby making the drill pipe string section less prone to fail due to rotational, tensile, and bending stresses.

Abstract: A method of measuring the internal taper (Miu) of an internally upset tube is disclosed along with the apparatus for practicing the method. The apparatus includes a first link mechanism that is operated to move a plurality of locating arms outwardly to a position near the inner wall of the tube. The locating arms are moved into the taper until the forward end of each arm is deflected toward the center of the tube far enough to pivot the other end into engagement with the tube and stop further movement of the first link mechanism. A second link mechanism is moved toward the outer end of the taper until it engages the taper adjacent its outer end. The distance between a reference joint on the first mechanism and a reference joint on the second is approximately the length of the taper.

Abstract: A joint of drill pipe is disclosed that has a tube section with upset ends to increase the wall thickness of the tube at its ends and tool joints connected to each end of the tube. Each tool joint has a cylindrical section connected to a weld neck of diameter by a tapered section. The connection between the tapered section and the weld neck has a radius of curvature and the weld neck has a wall thickness equal to that of the upset end of the tube that is welded to the weld neck. An external, stress relief groove is located in the weld neck to increase the fatigue life of the tube section of the drill pipe when the drill pipe is subjected to varying stresses produced by rotating the drill pipe while bent. One end of the relief groove is arcuate and is an extension of the radius of curvature between the tapered section and the weld neck. The groove may be arcuate in cross-section or it may have arcuate end sections with a cylindrical section between the end sections.

Abstract: The fatigue life of the tube section of a joint of drill pipe is increased by locating a stress relief groove in the weld necks of the tool joints adjacent the welds.

Abstract: A method is disclosed of externally and internally upsetting the end of a steel tube to provide a thicker wall for welding to a tool joint and for providing an internal tapered section having a projected length (Miu) along the longitudinal axis of the tube that substantially exceeds today's API standard upset. The method includes three upsetting steps, one pressing step, and one reheating step after the first two steps of the method.

Abstract: A method is disclosed for drilling a well bore having a vertical portion, a curved kick-off portion, and a horizontal portion. The length of the horizontal portion is extended by using drill pipe having an aluminum tube and steel tool joints to reduce the weight of the pipe string in the horizontal portion and reduce the friction resisting movement of the drill pipe along the low side of the well bore. In addition, the length of the joints of aluminum drill pipe is reduced to between 14-16 feet to substantially increase the buckling strength of each joint.

Abstract: An aluminum pipe joint is disclosed for use in a drill string for drilling wells having a well bore with a substantially non-vertical section where the portion of the drill string located in the non-vertical section is in compression and is urged into engagement with the low side of the hole by gravity. The pipe joint includes an elongated tubular member of aluminum the outer surface of which is a machined surface. The tubular member has an outside diameter equal to the outside diameter of a standard joint of drill pipe over a substantial portion of its length. A section of increased diameter is located about midway between the ends of the joint and portions of enlarged diameter are located adjacent each end of the pipe joint. The latter portions have a diameter equal to the diameter of the external upset required for tool joints. They also increase the buckling strength of the joint. Steel tool joints are attached to each end of the tube.