New One BHA Solution for High Dogleg Severity Curve and Lateral Drilling

Abstract

The highly productive Permian Basin requires wells with high dogleg severity (DLS) curve and long lateral sections. After many years of development and participation by all major industry players, most 8.5in size wells are still being drilled using two bottomhole assemblies (BHAs); one for the curve and a second for the extended lateral section. This increases cost, time, and risks. With development of our new solution, curve and lateral sections of Permian wells can now be consistently drilled in one run. Using in-house digital modeling and dynamic drilling simulation software of the complete drilling system and complex lithology profiles, design attributes were evaluated for directional performance before initial prototypes were created. These models increased efficiency and cost savings in the design process. Analysis revealed that shortening the distance from the RSS pad actuators to the bit (L1), increases the build-rate capability, increases the DLS output in the curve section, and provides tight trajectory control in long laterals. The system design also has a proprietary bit box connection and polycrystalline diamond compact (PDC) cutters on the bias unit. Prototype testing was done on high-DLS curve and lateral wells with major operators delivering wells per client requirements. The new solution successfully landed high DLS curve sections in 14 wells. The solution achieved a new milestone of delivering the 8.5-in curve on target and much faster than the conventional motor in the same application. After the curve sections the same BHA drilled into the long lateral section without making a trip between the curve and lateral sections. Several records were broken in some of these 14 wells, including 19% more daily footage than the previous record. Almost all these wells were also drilled using a remote operations center utilizing latest digital capabilities, reducing onsite footprint. Based on the most conservative figures from field test results and projected usage, the increased efficiency and faster well delivery time can significantly impact sustainability, reducing CO2 emissions per well drilled by this new solution.