煤矿井下长钻孔钻进减阻技术研究

Research on drag reduction technology for long boreholes drilling in coal mine

  • 摘要: 针对煤矿井下长钻孔钻进中钻杆柱与钻孔壁之间的摩擦阻力严重影响钻压传递、阻碍钻孔深度进一步增加的问题,对长钻孔钻进减阻技术进行了研究。分析了目前复合定向钻进技术存在的技术瓶颈,即复合钻进时无法定向,深孔滑动定向钻进时效率低,导致钻孔较深时无法开分支和纠偏;提出了水力振荡器减阻技术、滚轮扶正器减阻技术、冲击振动减阻技术及旋转导向技术等解决方案,分析了各方案的原理、技术优势及局限性,指出相关技术的地层适应性及对钻进设备的要求,并给出了相关技术的实际应用结果:淮南矿业集团张集矿使用水力振荡器后,平均给进表压为4 MPa左右,比使用前降低了33%,平均钻进效率比使用前提高了126%,压降消耗为2 MPa左右,泥浆泵压力虽升高1.7~2.5 MPa,但仍可满足目前煤矿井下钻进系统泥浆泵、定向钻具深孔钻进需要;采用单弯螺杆马达与液动冲击器复合钻具在唐家会煤矿现场共完成了2个定向试验钻孔,钻孔深度分别为546 m和564 m,使用该钻具组合施工进尺分别为411 m和429 m,用时分别为8 230 min和8 570 min,机械钻速约为3 m/h,而相同地层常规定向钻进的机械钻速为0.83 m/h,复合钻具的机械钻速提高了约260%;在晋煤集团寺河矿使用冲击螺杆马达钻进累计进尺1 743 m,累计时长为200 h,平均机械转速相较常规螺杆马达提高了20%~30%,可达8.34 m/h。提出开发小直径旋转导向技术是目前煤矿井下钻具突破的新方向。

     

    Abstract: In view of problem in long boreholes drilling in coal mine that frictional resistance between the drill string and the borehole wall seriously affects the transmission of weight-on-bit and hinders the further increase of the borehole depth, drag reduction technology for long borehole drilling were studied. Technical bottlenecks of the current composite directional drilling technology are analyzed, that is, it ca't be oriented in the composite drilling, and the efficiency is low in the deep hole sliding direction, as a result, it is impossible to develop branches and correct deviations when the drilling is deep. The solutions of hydraulic oscillator drag reduction technology,roller centralizer drag reduction technology,impact vibration drag reduction technology and rotary steering technology were proposed, and the principles, technical advantages and limitations of each scheme were introduced, and the stratum adaptability of related technologies and the requirements for drilling equipment were pointed out. The actual application results of the related technology were put forward:after application of hydraulic oscillator in Huainan Mining Group Zhangji Mine,average feed gauge pressure was about 4 MPa, which was 33% lower than before, and the average drilling efficiency was increased by 126%, the pressure drop consumption was about 2 MPa, although the mud pump pressure increases to 1.7-2.5 MPa, it could still meet the needs of mud pumps in current coal mine underground drilling system and deep hole drilling with directional drilling tools;Two directional test boreholes were completed on the site of Tangjiahui Coal Mine with single-bend screw motor and hydraulic impactor compound drilling tool,and the drilling depths were 546 m and 564 m,the construction footage using the drilling tool combination were 411 m and 429 m,the time were 8 230 min and 8 570 min respectively, and the ROP was about 3 m/h,while the ROP of conventional directional drilling in the same formation was 0.83 m/h,the ROP of composite drilling tools increased by about 260%;Impact screw motor was used in Sihe Mine of Jinmei Group for drilling footage of 1 743 m, the cumulative time was 200 h, and the average mechanical speed could reach 8.34 m/h, which was 20%-30% higher than the conventional screw motor.It was proposed that the development of small-diameter rotary steering technology is a new break through direction for underground drilling tools in coal mines.

     

/

返回文章
返回