Drill Faster, Deeper, and Further With Ultrahigh-Torque Third-Generation Double- Shoulder Connections

摘要

New developments in drilling tubulars are rapidly evolving and represent enabling technologies for the industry’s continued advancement of drilling deeper, further and more cost-effective wells. Much focus has been made toward the advancement of drill pipe connection technology to permit high torque drilling of extended reach, directional and horizontal wells. First and second generation high torque connections have been available to the industry for several years. In today’s rig market; deepwater, extended reach and ultra- deep wells dictate large spread rates that can benefit significantly from reduced tripping times. These same wells often have mechanical and hydraulic load requirements for which today’s high torque connections may not be specifically optimized. In response to this need, the development of third generation, ultra-high torque connections is now complete. This paper will present the results of a 2-1/2 year comprehensive effort to design, test, manufacture and field trial a family of connections that were engineered to meet the specific needs of each drill pipe size. Results from extensive laboratory tests and two field trial programs designed to produce harsh, aggressive dynamic loads to the connections are presented. The thread form is a double-start thread that reduces the number of revolutions to assemble the connection by 50%. The thread form also provides a unique dual-radius thread root that offers a step change improvement in fatigue resistance. Conservative estimates suggest that the new connections will save approximately 7-1/2 hours in planned trip time per 20,000 ft well. The new connections provide increased mechanical and hydraulic performance compared to second generation high torque connections while also providing fatigue performance greater than standard API connections. These connections can facilitate more challenging wells, provide increased cost savings and reduce risk during the well construction process.