Grant Prideco, Inc.

Prideco, Inc.

Gerald E Wilson

Jackie E Smith

Thomas Edward Winship

R Thomas Moore

Wei Tang

A tubular drill pipe section to be used in a well bore is disclosed. The drill pipe section includes upper and lower tool joints, a main steel tubular portion extending upwardly from the lower joint and terminating near the upper tool joint, and an elongated steel protector tube extending downwardly from the upper tool joint and secured to the upper end of the main portion. The main portion has a much lesser wall thickness throughout substantially its entire length than the protector tube. The protector tube is made of AISI 4100 series chrome-molly steel that is quenched and tempered to give it high strength and high hardness (30-38 HR ) with a Martensite small, close knit, grain size. This hard material reduces the penetration of the slip teeth into the wall of the pipe section and increases the fatigue life of the protector to beyond that of the main steel tubular portion.

Fatigue resistant drill pipe

A heavy weight drill pipe member is disclosed for use in drilling high angle and horizontal well bores in a corrosive environment. The heavy weight drill pipe member consists of a tubular member with a longitudinal bore therethrough, and includes connectors or tool joints attached at each distal end for connecting additional heavy weight drill pipe members. The tubular member and tool joints are preheated, water quenched and tempered to obtain a unique combination of hardness, a yield strength and impact strength for improved resistance to stress corrosion cracking and hydrogen embrittlement in a hydrogen sulfide environment. The tubular member includes a plurality of wear pads or protectors equidistantly spaced along the longitudinal axis of the tubular member to reduce bending stress in the pipe by limiting the degree of bend when the pipe is placed in compression in a high angle well bore. To reduce the chances of differential pressure sticking of the pipe when the pipe is used in high angle or horizontal well bores, each wear pad or protector is provided with spiral grooves therein. Each wear pad or protector may also be hard faced or hard banded to reduce wear.

Heavy weight drill pipe

An ultra high torque double shoulder tool joint (see FIG. 1) for maximizing the torsional strength of a threaded connection by correlating a transverse cross-sectional counter-bore area of the box (12) and pin (10). The pin 10 includes a base section 74 and a nose section 24. The nose section 24 defines a cross-sectional nose area 28. The pin external threads 22 include a taper no greater than 1/12. The box 12 includes a cross-sectional counterbore area 46 and a cross-sectional box area 52. The overall strength of the tool joint is dependent upon the torsional strength of the threaded connection, the cross-sectional nose area (28) and the cross-sectional counter-bore area (46).

Ultra high torque double shoulder tool joint

A tubular drill pipe section to be used in a well bore is disclosed. The drill pipe section includes upper and lower tool joints, a main steel tubular portion extending upwardly from the lower joint and terminating near the upper tool joint, and an elongated steel protector tube extending downwardly from the upper tool joint and secured to the upper end of the main portion. The main portion has a much lesser wall thickness throughout substantially its entire length than the protector tube. The protector tube is made of AISI 4100 series chrome-molly steel that is quenched and tempered to give it high strength and high hardness (30-38 HR.sub.c) with a Martensite small, close knit, grain size. This hard material reduces the penetration of the slip teeth into the wall of the pipe section and increases the fatigue life of the protector to beyond that of the main steel tubular portion.

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.

Stress relief groove for drill pipe

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.

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.

Method of horizontal drilling

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. The length of the enlarged end portions is such that the joint will not be bent during tonging if the joint is supported adjacent the end of the enlarged portion on which the tool joint being tonged is located.

Growing community of inventors

Montgomery, TX, United States of America

Gerald E Wilson