Research on the Dynamic Characteristics of Drill String Rotation Orientation Tool

Abstract To address the issues of low drilling efficiency in horizontal wells, new anti-friction or drag-reducing tools are effective methods in solving these issues, which are also hot topics to improve the rate of penetration (ROP). This article innovatively presents a drilling string rotary orientation tool, which aims to improve the drilling efficiency. For the discovery of its internal mechanism, a multi-degrees-of-freedom drill string dynamic model is established based on the engineering background. Meanwhile, the dynamic response results are analyzed to study its performance. The results indicate that when utilizing this tool, both the upper and lower limits of drill string elements’ axial displacement change significantly, and also the fluctuation range decreases significantly. Furthermore, the article analyzes the influence of weight on bit (WOB) and driving torque on the system’s performance, with the case study, it finds out that the driving torque has a more obvious influence on the system than the WOB. Specifically, as driving torque increases, the fluctuation range of axial displacement diminishes. Then, by analyzing the axial displacement’s lower limit, this designed tool demonstrates the advantages of reducing vibration displacement and increasing the ROP by evaluating the wear-rate results, and it consistently reduces by above 60%. It was found that the innovative design is effective in suppressing the axial vibrations and enhancing the drilling trajectory control performance significantly.