The Next Generation Top Drive and Lessons Learned from the TDX-1250

Abstract

With all the emphasis today on the economics of improving well costs, the industry is faced with finding a way to provide marketable technology to drill more challenging wells even cheaper. The top drive stands out as one of a few key pieces of equipment in the critical path. As a result Top Drive failures have accounted for a large portion of down time, thereby increasing costs to drill a well, and the top drive is in essence "the drill" needed to reach reservoirs that are farther and deeper than once thought possible.ExxonMobil needed to upgrade its drilling platform in the Yastreb field in order to reach reservoirs with very long, extended reach. Drilling these wells necessitated a need for more torque and speed. Typically these parameters are supplemented with downhole motors. However, in extended reach wells, failure 5,000 -6,000 feet downhole costs up to a full day to retrieve the equipment and another full day to re-deploy the tool. With performance improvements to today's modern top drive, we have been able to increase torque and speed on the top drive and move that associated risk to the rig floor.Today's ultra-deepwater drilling necessitates durable, maintenance friendly top drives to off-set the high day rate and spread costs associated with these wells. For that, top drives in this environment have taken a step-change to increase durability with larger main thrust bearings, larger main shaft connections, heavy-duty link tilt function, etc. In addition to this increased focus on durability, these machines also need to be repaired quickly to get them running again. This has created a new generation focused on maintainability, and modularity.