万米特深井机械式自动垂直钻井技术研究进展与展望

Research progress and prospects of mechanical automatic vertical drilling technology for ultra-deep wells

摘要:

随着大陆科学钻探向万米特深井迈进，井底超300 ℃、175 MPa的极端工况导致电控垂钻系统失效，机械式垂钻技术凭借纯机械结构与300 ℃耐温潜力，成为超高温深井防斜打直的核心手段。本文系统梳理了机械式垂钻技术的工作原理与研究进展，对比分析了国内外代表性产品的结构特点与应用效果，指出国内外在纠斜精度、耐温能力和工程化程度方面的显著差距。在此基础上，剖析机械式稳定平台动力学响应、新型推靠执行机构、高温材料与密封三大关键技术问题，指出现有翼肋推靠式系统存在导向能力对地层敏感、翼肋易磨损及稳定平台受黏滑振动影响导致纠斜精度下降等不足。未来应重点突破纠斜精度提升、耐300 ℃高温材料研发、多场耦合动力学机理研究及国产化工程应用，推动执行机构从“翼肋推靠”向“钻头流体导向”跨越式升级，为万米级大陆科学钻探工程提供技术支撑。

Abstract:

As continental scientific drilling advances toward 10000-meter ultra-deep wells， the extreme downhole conditions of temperatures exceeding 300 ℃ and pressures over 175 MPa render electrically-controlled vertical drilling systems ineffective. Featuring a purely mechanical structure and a temperature resistance potential of up to 300 ℃， mechanical vertical drilling technology has become the core solution for deviation prevention and straight-hole drilling in ultra-high temperature deep wells. This paper systematically reviews the working principles and research progress of mechanical vertical drilling technology， comparatively analyzes the structural characteristics and field application performance of representative domestic and international products， and identifies significant gaps between China and foreign countries in deviation correction accuracy， temperature resistance， and engineering maturity. On this basis， three key technical issues are examined： the dynamic response of the mechanical stabilization platform under downhole vibrations， innovative push-the-bit actuators， particularly the bit fluid steering concept， and high-temperature materials and sealing. It is pointed out that existing rib-type push-the-bit systems suffer from the inherent limitation of formation-sensitive steering performance， rib wear， and the degradation of deviation correction accuracy caused by stick-slip vibration affecting the stabilization platform. Future research should focus on improving deviation correction accuracy， developing materials resistant to 300 ℃， investigating multi-field coupled dynamic mechanisms， and advancing domestic engineering applications， thereby promoting a transformative upgrade of the actuator from "rib-type pushing" to "bit fluid steering" and providing technical support for 10000-meter continental scientific drilling projects.