彬长矿区高家堡矿井大直径排水钻孔施工技术

Construction Technology of Large Diameter Drainage Drilling in Gaojiabu Minefield,Binchang Mining Area

摘要:

彬长矿区高家堡矿井位于黄陇侏罗纪煤田中部，主采煤层上覆洛河组砂岩含水层，具巨厚、低渗、富水性不均等特点，随着开采深度增加，矿井水害严重威胁安全生产，现有排水系统难以满足需求，急需扩容。为此构建集中排水系统，实施大直径排水钻孔施工，成孔直径Φ950mm，深810m，开创性地利用“套管内径大小头+焊接螺纹钢筋圈+预制钢筋钩”制作套管水泥浮力塞的方法，安装了378.8t排水管路。在该地区实施大直径排水钻孔施工中，钻遇地层条件复杂，易发生孔壁垮塌、缩径卡钻等事故，施工穿越巨厚洛河组砂岩含水层，部分孔段岩石可钻性差，钻进效率较低，工程整体难度大。针对此类问题，本文提出了控制钻井液失水、优化钻具组合和维护钻井液性能等针对性解决措施，取得了良好的实践应用效果，为矿区水害防治提供了可行性方案。

Abstract:

Abstract: The Gaojiabu Mine in the Binchang mining area is located in the middle of the Huanglong Jurassic coalfield. The main coal seam is overlaid by the Luhe Formation sandstone aquifer, which is characterized by great thickness, low permeability and uneven water abundance. As the mining depth increases, water hazards in the mine seriously threaten safe production. The existing drainage system is unable to meet the demand and needs to be expanded. Therefore, a centralized drainage system was constructed, and large-diameter drainage boreholes were implemented, with a borehole diameter of Φ950mm and a depth of 810m. A novel method was adopted to fabricate the casing cement buoyancy plug using "casing inner diameter reducer + welded threaded steel ring + prefabricated steel hook", and 378.8t of drainage pipelines were installed. During the construction of large-diameter drainage boreholes in this area, complex geological conditions were encountered, and accidents such as hole wall collapse and stuck pipe due to reduced diameter were prone to occur. The construction passed through the thick Luhe Formation sandstone aquifer, and the rock drillability was poor in some sections, resulting in low drilling efficiency and high overall project difficulty. To address these issues, this paper proposed targeted solutions such as controlling drilling fluid loss, optimizing drill string combinations, and maintaining drilling fluid performance, which achieved good practical application results and provided a feasible solution for water hazard prevention and control in the mining area.