煤矿井下定向钻进用刮刀型PDC钻头的研制与应用

Development and Application of Drag PDC Bit for Directional Drilling in Underground Coal Mine

在煤矿定向钻进过程中,由于钻孔深度可达千米以上,钻进地层也从单纯煤层逐步转移到复杂多变的岩层。在井下地层条件比较复杂、岩性种类较多的长距离钻孔钻进过程中,普通PDC钻头经常会发生磨损、冲蚀等现象,且寿命和时效不能满足使用要求。针对这一问题,研制了一种刮刀型PDC钻头,钻头采用刮刀型浅内锥结构,可以排布更多切削齿,具有良好的排粉效果,并可根据地层情况进行调整钻头切削角与侧转角。通过现场试验证明,在岩层定向钻进中使用效果良好。

In the process of directional drilling in coal mine, as the drilling depth can be over 1000m, the drilling formation can change from coal gradually to complex strata. In the long depth drilling in complex formation, common PDC bit is easily worn and washed out, whose life and aging cant be ensured. A drag type PDC bit is developed aiming at this problem. In the bit, drag type and shallow cone structure is used, more cutters can be arranged. The cutting angle and the side angle are chosen according to the formation. The bit was used in the underground directional drilling, and good effect was achieved.