矿井瓦斯抽采钻孔偏移特性研究  

Study on deviation characteristic of gas extraction borehole drilling in underground coal mine

作　　者：杜栋栋 雷文杰[1] 李东会[1] 李哲 DU Dongdong;LEI Wenjie;LI Donghui;LI Zhe(School of Safety Science and Engineering,Henan Polytechnic University,Jiaozuo Henan 454000,China)

机构地区：[1]河南理工大学安全科学与工程学院,河南焦作454000

出　　处：《中国安全科学学报》2024年第3期155-161,共7页China Safety Science Journal

摘　　要：为避免井下瓦斯抽采钻孔发生轨迹偏移,出现瓦斯抽采盲区,产生瓦斯抽采空白带,首先以山西阳泉新景煤矿15121底抽巷、15124低位巷、15124回风巷为工程背景,测试穿层钻孔和顺层钻孔的偏移情况;然后利用均角全距法计算钻孔三维轨迹数值,并结合煤层赋存地质信息,绘制钻孔三维轨迹与煤岩三维层位关系可视化图,分析影响钻孔偏移的因素和拟合数据,并得出钻孔偏移特性。研究表明:穿层钻孔主要在细砂岩层开始偏移,且均在煤层段偏移变大,煤层段最大偏移量为0.52 m;顺层钻孔开孔倾角相近时,孔深越深终孔垂直偏差越大,40 m孔深平均垂直偏移量为1.37 m;小角度钻孔受重力影响较大,轨迹易发生偏移,大角度钻孔在垂直方向上向上或向下偏移,偏移量比小角度钻孔偏移量小;在水平方向上,底抽巷、低位巷、回风巷布孔间距分别缩短0.68、0.28、0.54 m。During the construction of underground extraction boreholes,trajectory deviation is common,prone to blind gas extraction areas and produces gas extraction blank zones.In order to ensure that gas extraction achieves the expected results,the 15121 bottom pumping lane,15124 low level lane and 15124 return air lane of Xinjing mine in Shanxi province were taken as the background of the project.We tested the deviation of borehole drilling through the seam and along the seam respectively,calculated the three-dimensional trajectory of the drill holes by using the mean angle full distance method,established the three-dimensional trajectory of the drill holes and the three-dimensional layer relationship of coal rock based on the geological information of coal seam assignment,realized the visualization of the trajectories of the drill holes,analyzed the factors affecting the deviation of the drill holes and the experimental fitting data,and came up with a characteristic of the deviation of the boreholes.The research findings suggest that cross-layer boreholes initially exhibit deviation within fine sandstone layers,with the deviation intensifying notably within the coal seam segment,reaching a maximum deviation of up to 0.52 meters within this section.In the case of in-seam drilling,greater drilling depth results in larger vertical deviations,with an average vertical offset of 1.37 meters at a depth of 40 meters when the opening angles of boreholes are similar.Overall,low-angle boreholes are more susceptible to gravity-induced deviations,leading to a higher likelihood of trajectory deflection,while high-angle boreholes tend to exhibit vertical deviations,albeit with a smaller overall deviation compared to low-angle boreholes.In the horizontal direction,borehole spacing is reduced by 0.68 meters for bottom drainage galleries,0.28 meters for lower position galleries,and 0.54 meters for return airways.The research results effectively guide the design of subsequent gas extraction drilling trajectories under the same geological

关 键 词：瓦斯抽采 穿层钻孔 顺层钻孔 三维轨迹 偏移特性 布孔参数 

分 类 号：X936[环境科学与工程—安全科学]