新型棘轮式二级定位钻具内切割器研制及其在近水平定向钻孔中的应用

Development of a new ratchet type two-stage positioning drill internal cutter and its application in near horizontal directional hole

随着套铣技术在煤矿井下近水平定向钻孔卡/埋钻事故中的应用越来越多,套铣钻具发生二次卡/埋钻事故概率增加,针对该问题,在常规水力式机械内切割器的基础上,设计了一种用于煤矿井下近水平定向钻孔套铣钻具的棘轮式二级定位小口径内切割器;通过建立推送装置与切削刀的几何模型得到了二者的位移关系,并确定了棘轮式二级定位小口径内切割器的技术参数;现场应用中成功将φ114 mm套铣钻杆在446.5 m处割断。结果表明:活塞与节流针配合起到了切割报信功能;采用的具有定位功能的棘轮机构,降低了对连续水压的依赖,操作难度要求降低;利用弹簧蓄能为切削刀刀具旋转提供柔性推力,推力连续稳定,消除了水压波动对刀尖的冲击。

With the increasing application of milling technology in near-horizontal directional drilling stuck/buried drilling accidents in coal mines,the probability of second stuck/buried drilling accidents with milling tools increases.To solve this problem,based on the conventional hydraulic mechanical internal cutter,a ratchet type two-stage positioning small diameter internal cutter was designed for the milling tool of near-horizontal directional drilling in underground coal mine;the displacement relationship between the push device and the cutting tool was obtained by establishing the geometric model,and the technical parameters of the ratchet two-stage positioning small diameter internal cutter were determined.In the field application,the casing milling drill pipe with a diameter of 114 mm was cut off successfully at 446.5 m.The results show that the piston and the throttle needle cooperate to cut the signal function;the ratchet mechanism with positioning function is adopted to reduce the dependence on continuous water pressure and reduce the operation difficulty.Using spring energy storage to provide flexible thrust force for cutting tool rotation,the thrust is continuous and stable,and the impact of water pressure fluctuation on tool tip is eliminated.