小口径金属矿产勘探钻探关键技术研究与应用

Research and application of key technologies for small-diameter drilling in metallic mineral exploration

摘要:

为应对深部及复杂地层小口径金属矿产勘探的挑战，本文针对硬岩地层钻进效率低、小口径钻孔轨迹控制难、复杂地层孔壁稳定性差及环保要求严等关键问题，系统开展了4项关键技术研究与应用：针对坚硬低研磨性地层，优化钻头设计（复合胎体、金刚石参数、水力结构）与钻进参数（高钻压、中转速），机械钻速提升超100%；针对易斜地层，集成防斜钻具与?32 mm MWD，提出“主动防斜+动态纠偏”方法，实现钻孔偏斜率≤1.5°/100 m；针对破碎、漏失地层，研发地层适配性低固相/无固相冲洗液体系及自适应调控方法，结合随钻跟管、桥接堵漏等技术，有效解决垮孔、缩径及冲洗液漏失问题；创新融入绿色勘查理念，应用高效低扰动钻机、环保冲洗液、岩屑闭环处理等技术，显著降低环境扰动。在霍邱铁矿区应用表明，该技术体系可显著提升钻探效率，降低勘探成本与钻孔事故率，为深部金属矿产高效、精准、绿色勘探提供了可靠技术支撑。

Abstract:

To meet the challenges of small-diameter drilling for metallic mineral exploration in deep and complex formations， this study addresses four critical issues： low penetration rates in hard rock， difficulty in borehole trajectory control， poor borehole stability in broken or lost-circulation strata， and stringent environmental constraints. Four key technologies were developed and implemented：（1） For hard， low-abrasivity formations， bit design （composite matrix， diamond specification， hydraulic configuration） and drilling parameters （high weight-on-bit， moderate rotary speed） were optimized， raising the rate of penetration by more than 100%. （2） In deviation-prone formations， an anti-deviation bottom-hole assembly coupled with a ?32mm mud-pulse MWD system was deployed， enabling a “proactive deviation prevention + dynamic correction” strategy that limits borehole deviation to ≤1.5°/100 m. （3） Formation-adapted low-solid/non-solid drilling fluid systems with adaptive control， combined with drilling-with-casing and bridging lost-circulation materials， effectively mitigate collapse， diameter reduction and mud losses. （4） Green exploration principles were integrated through low-disturbance rigs， environmentally benign drilling fluids and closed-loop cuttings management， markedly reducing environmental impact. Field trials in the Huoqiu iron deposit demonstrate significant improvements in drilling efficiency， cost reduction， and accident-rate decline， providing a robust technical foundation for efficient， accurate and environmentally sustainable deep mineral exploration.