矿山救援地面生命保障孔高效成孔关键技术

地面生命保障孔作为井下被困人员的保障通道，是矿山事故造成人员被困井下时重要的地面应急救援方案之一，面对救援区易坍塌、易漏失、涌水大、易斜地层等复杂条件，单一成孔工艺存在地层适应性匹配差、综合钻进效率低、透巷难度大等问题，无法满足救援要求。为形成生命保障孔高效成孔工艺技术体系，提高应急救援响应速度，从解决钻效低、透巷难等科学问题和关键技术入手，快速安全钻进和精准透巷是高效成孔的两个核心任务:围绕快速安全钻进，针对深厚覆盖层、复杂基岩层，开展高压射流、空气潜孔锤跟管、复合钻进、空气潜孔锤、双钻头自平衡等钻进工艺研究，形成了深厚覆盖层安全高效钻进、基岩层复合“一趟钻”提速增效、基岩层空气潜孔锤“一趟钻”提速增效等安全快速钻进技术组合；围绕精准透巷，依据不同钻进工艺孔身轨迹控制机理，阐述了复合钻进轨迹监测控制与空气钻进轨迹监测关键技术方法，针对应急救援现场大偏移井无法透巷难题，提出了超短距离螺旋纠偏技术。成果应用于宁夏梅花井矿生命保障孔工程试验，钻孔深度670.50 m，成孔孔径215.9 mm，用时46.83 h，平均钻速14.32 m/h，孔底水平偏移0.27 m，从开钻至下套管高效成孔总用时55 h，证明该工艺技术体系能确保生命保障孔在72 h黄金救援时间内高效成孔，为地面应急救援钻孔的施工提供技术支持。 

Key technologies of surface efficient life support hole forming for mine rescue

The surface life support hole, as the support channel for the trapped people underground, is one of the important ground emergency rescue schemes for the situation with some people trapped underground due to mine accidents. Under the complex conditions of the rescue area, including easy collapse, easy leakage, large water inflow and inclined formation, the single hole forming process has the problems such as poor ground adaptability matching, low comprehensive drilling efficiency and difficult roadway penetration, which cannot meet the requirements of rescue. In order to form an efficient drilling technology system for life support holes and improve the response speed of emergency rescue, it is determined from the point of solving the scientific and key technical problems such as low drilling efficiency and difficult roadway penetration that rapid and safe drilling and accurate roadway penetration are the two core tasks of efficient drilling: Focusing on rapid and safe drilling, researches were conducted on the drilling technologies such as high-pressure jet, air DTH hammer with casing, composite drilling, air DTH hammer, and double bit self-balance for the thick overburden and complicated bedrock, thus forming a combination of rapid and safe drilling technology for the safe and efficient drilling in deep overburden, the speed and efficiency improvement of compound one-trip drilling in the overburden, and the speed and efficiency improvement of one-trip drilling in the bedrock with air DTH hammer. As for the accurate roadway penetration, the key technical methods of compound drilling trajectory monitoring and control, as well as air drilling trajectory monitoring, were expounded for the borehole trajectory control mechanism of different drilling processes. Meanwhile, an ultra-short distance spiral deviation correction technology was proposed based on the failure of roadway penetration in large offset wells at the emergency rescue site. The results were applied to the engineering test of life support holes in Meihuajing Mine, Ningxia. Specifically, the borehole, with a depth of 670.50 m and a diameter of 215.9 mm, was drilled at an average speed of 14.32 m/h in 46.83 h, of which the horizontal displacement at the bottom was 0.27 m, and 55 h was taken in total from spud-in to casing running. Hence, it is proved that the technology system could ensure the efficient completion of life support holes within the 72-h golden window, providing technical support for the construction of surface borehole for emergency rescue.