大倾角碎软低渗煤层下向长钻孔工艺研究与应用  

Research and application of downward long drilling technology in large inclined broken soft and low-permeability coal seam

作　　者：赵坤 刘佩 ZHAO Kun;LIU Pei(CCTEG Chongqing Research Institute,Chongqing 400037,China)

机构地区：[1]中煤科工集团重庆研究院有限公司,重庆400037

出　　处：《矿业安全与环保》2023年第2期93-96,共4页Mining Safety & Environmental Protection

摘　　要：针对新疆艾维尔沟矿区大倾角碎软低渗煤层,设计了一种高性能三棱螺旋钻杆,其转矩性能更优,同时具备更大的排渣通道与更佳的孔壁稳定性,三棱螺旋结构既提高了钻杆的排渣效率,又可在钻遇碎软煤层时通过旋转钻杆、反复洗孔等方式有效解决由于垮孔、塌孔造成的卡钻、埋钻问题,可有效提高碎软煤层钻进深度。揭示了螺旋型三棱钻杆不同孔深段所需风压:孔深0~50 m时风压为0.44 MPa、孔深50~100 m时风压为0.53 MPa、孔深100~150 m时风压为0.61 MPa、孔深150~200 m时风压为0.67 MPa,并提出一套适用于大倾角碎软低渗煤层下向长钻孔钻进施工工艺。针对2130煤矿25222运输巷,在下帮施工20个下向长钻孔并开展了下向长钻孔排采试验,在排采的60 d内,甲烷抽采纯流量前10 d由0.10 m^(3)/min快速降低至0.04 m^(3)/min、之后30 d由0.04 m^(3)/min缓慢降低至0.02 m^(3)/min、最后20 d由0.02 m^(3)/min缓慢增加至0.04 m^(3)/min,达到了排采试验目标。试验结果表明,采用三棱螺旋钻杆+中风压排渣钻孔工艺能够有效解决常规回转钻进成孔率低、孔深浅、工期长的问题,利用下向长钻孔解决工作面条带瓦斯抽采在新疆艾维尔沟矿区的推广应用奠定了基础。In this paper,a high-performance three-edged auger drill rod was designed for the large inclined broken soft and low-permeability coal seam in Aiweiergou mining area of Xinjiang,which has better torque performance,larger slag discharge channel and better hole wall stability.The three-edged auger structure not only improves the slag discharge efficiency of the drill rod,but also effectively solves the stuck drilling and buried drilling accidents caused by the caving hole and collapsed holes by rotating the drill rod and repeated hole washing when drilling into broken soft coal seams.It can effectively improve the drilling depth of broken soft coal seam.The wind pressure required for different hole depths of three-edged auger drill rod is revealed:0.44 MPa for hole depths of 0 m to 50 m,0.53 MPa for hole depths of 50 m to 100 m,0.61 MPa for hole depths of 100 m to 150 m,0.67 MPa for hole depths of 150 m to 200 m.A set of construction technology is proposed for long-hole drilling in large inclined broken soft and low-permeability coal seam.For the 25222 headentry in the 2130 Coal Mine,20 downward long boreholes were constructed in the lower wall and the drainage test of downward long boreholes was carried out.Within 60 days of drainage,the pure methane extraction volume decreases rapidly from 0.10 m^(3)/min to 0.04 m^(3)/min in the first 10 days,slowly decreases from 0.04 m^(3)/min to 0.02 m^(3) in the next 30 days,and slowly increases from 0.02 m^(3)/min to 0.04 m^(3)/min in the last 20 days,reaching the target of the drainage test.The test results show that the use of three-edged auger drill rod+medium wind pressure slag discharge drilling process can effectively solve the problems of low porosity,shallow hole depth and long construction period of conventional rotary drilling.It lays a foundation for the application and popularization of the technology to solve the strip gas in the working face by using downward long borehole in Aiweiergou mining area in Xinjiang.

关 键 词：大倾角 碎软低渗煤层 下向长钻孔 三棱螺旋钻杆 排采试验 

分 类 号：TD712[矿业工程—矿井通风与安全]