Active Control of Drillstring Axial Wriggle: Tool Development and Field Validation

Summary Efficient transfer of weight on bit (WOB) in long horizontal wells remains a key challenge in drilling operations. In this study, we present a segmented drillstring axial creep tool (ACT) that integrates single-point hydraulic excitation with multipoint mechanical vibration to enhance friction reduction and WOB transmission. A Φ175-mm prototype, designed based on biomimetic principles inspired by earthworm peristalsis, was developed and evaluated through laboratory and field tests. Laboratory results show that at flow rates of 20–36 L/s, the ACT generated near-sinusoidal pressure pulsations with a maximum amplitude of 2.55 MPa and a frequency of 2.75–7.8 Hz, corresponding to an axial excitation force up to 48 kN. Field applications in three horizontal wells demonstrated rate of penetration (ROP) improvements of 15.5–92.2% compared with conventional friction-reduction tools, without additional pressure drop. The ACT operated reliably for 350.5 hours, confirming its durability and stability. These findings verify the ACT’s capability to significantly enhance drilling efficiency and provide practical guidance for optimizing friction-reduction tools in extended-reach well drilling.