贵州省水城509队自从55年建队到现在已有两年的时间，但因矿区地质构造复杂，岩性变化太不易掌握，到目前为止岩矿心采取仍很困难，经常有打掉矿层和岩矿心采取率不能满足国家要求报废钻孔的情况，据统计57年上半年该队需要补斜的钻孔共有24个（其中包括56年8个钻孔）给国家造成巨大的损失，但在使用孔底反循环钻具后（水城队侯振山老师傅所创造），据4个工区6个机场的不完全统计，在五、六、七级灰岩中用91—110公厘合金钻头钻进，纯钻时间12小时共进尺84.43公尺，取得岩心77.29公尺采取率达到90％机械钻进效率0.64公尺/时，基本上解决了脆破碎及松软地层岩矿心采取问题，代替了无泵钻具和双层岩心管，而且提高了钻进效率，但 Guizhou Province Shuicheng 509 team has been building a team for 55 years since it has been two years now, but because of the complex geological structure of the mine and the change of lithology is too difficult to grasp, so far the core of rock is still difficult to take, and often have to destroy the mine and According to the statistics, a total of 24 drilling holes (including 8 bore holes of 56 years) needed to be compensated for by the team in the first half of 57 were tremendous losses to the country. However, After using the hole bottom reverse circulation drill (Shuicheng Hou Zhenshan master created), according to the incomplete statistics of 6 airports in 4 workplaces, 91-110 mm alloy drill bits are used in limestone of five, six and seven levels Into the pure diamond 12 hours 84.43 meters, 77.29 meters core access rate of 90% to achieve mechanical drilling efficiency of 0.64 meters / h, basically solved the brittle crushed and loose formation rock core take the problem, instead of No pump drill and double core pipe, but also improve the drilling efficiency, but