New Bit Design with Rotary Steerable System Unlocks Next Drilling Chapter: Improving DLS Capability and Drilling Performance

Abstract

Abstract One of the biggest challenges in drilling operations is achieving the required dogleg severity (DLS) while drilling the landing curve section in 3D complex wells, especially the wells targeting shallower reservoirs that demand high DLS. This manuscript describes the first use implementations of a new bit design in the Middle East with a Rotary Steerable System (RSS) that achieves demanding DLS with avoiding usage of Positive Displacement Motor (PDM) in the directional bottom hole assembly (BHA), which could have compromised the drilling performance. Dynamic modeling was performed to simulate the interaction of RSS and motorized RSS with the new bit design to model the DLS capability, shock and vibration, stick and slip, and BHA stability. The formation properties and response to different steering ratios were also included to have a comprehensive study of the fields. Furthermore, optimized drilling parameters regarding the flow rate, weight on the bit (WOB), and rotation per minute (RPM) were modeled to reach the best performance with increasing efficiency to mitigate shocks and vibrations and, at the same time, reduce stick and slip. The complex 3D design was drilled with shallow true vertical depth (TVD), successfully meeting the client’s requirement. The challenge of the high DLS and having low performance is now a thing of the past, as a new chapter has been opened with the new bit design with rotary steerable BHA. The first trials with the new bit were successful. The required shallow TVD was achieved with up to 6 deg/100 ft of DLS. Moreover, there was no need to set the maximum steering ratio for the RSS tool, as the required DLS was achieved by using only 50% of its capability. On the other hand, operating the RSS tool with half its energy has increased its reliability, almost doubling its life span, which means longer sections can be drilled with one run in the future. However, with these new technologies, there is no need to run the motors with a high bend angle to get the DLS; this can be done by using the new bit design and the RSS tool. Furthermore, controlling the rate of penetration (ROP) to get a higher DLS was not necessary, as it resulted in increased performance with a smooth well trajectory.