Key Technical Research for Single-trip Drilling Through Build-up and Horizontal Sections of Deep Shale Gas Horizontal Wells
The geological conditions of shale gas with reservoir depth greater than 3 500 m in Sichuan Basin are complex,the drilling engineering is faced with the challenge of high bottomhole temperature and high kick-overflow risk,and the ratio of single-trip drilling through build-up and horizontal sections in deep shale gas horizontal wells is low,which leads to long drilling cycle and high engineering costs.This paper systematically summarizes the difficulties and challenges in achieving"single-trip drilling"for deep shale gas in southern Sichuan,analyzes the influencing factors such as complex geological structures,target formation temperature,formation pressure,and drilling fluid properties,and reviews the current key technological advancements and application results in"single-trip drilling"in this area.Based on these findings,the paper proposes research directions and recommendations,including the precise control of drilling fluid density and ECD,studies on borehole heat transfer and phase-change cooling materials,and the testing of"slim hole"drilling technology,taking into account factors such as geology,well structure,wellbore trajectory,drilling fluids,and equipment.
unconventional oil and gasdeep shale gashorizontal wellsingle-trip drilling