膨润土的可钻性不过1～2级，钻进中虽然钻速较高，但因其松软且遇水膨胀（岩心伸长率达130～150％），用常规方法很难取心。为保证采取率，在勘探初期，我们曾采用无泵钻进取心，但这种方法回次长度和效率都很低。为了提高效率，我们也曾使用过开泵钻进干钻取心。但干钻的时间不好掌握，过长常出现烧钻、糊钻事故；过短则又出现卡心不牢造成岩矿心脱落。为解决效率与取心的矛盾，我们经过多 Bentonite drillability but 1 to 2, although the drilling rate is high, but because of its soft and water expansion (core elongation of 130 to 150%), using conventional methods is difficult to corral. In order to ensure the adoption rate, we used no-pump drilling in the early stage of exploration, but this method was of low length and low efficiency. In order to improve efficiency, we also used to drill into the dry drilling heart. However, the time of dry drilling is not good to grasp, too often appear burns, paste accident; too short card center is not strong cause rock core fall off. In order to solve the contradiction between efficiency and coring, we have passed many