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出 处:《世界地质》2001年第2期206-208,共3页World Geology
摘 要:由于地层较为复杂 ,采用普通潜孔锤钻进方法难以成孔 ,实践证明 ,风动潜孔锤跟管钻进技术是破碎复杂地层中钻进成孔最为有效的方法。下锚结束后 ,应及时将套管从孔中拔出 ,单纯依靠钻机自身提引力很难实现 ,采用潜孔锤向上反击起拔套管 。It is difficult to drill a hole using common DTH Hammer drilling technique for the complex formation. It proved that the case following DTH drilling is the most effective method in these complicated formations. The case should be pulled up in time after the prestress anchor cable is over and this process is difficult to realize depending only on the pulling power of the rig. Using the DHT reverses impacting to pull the case protect the rig and save time of the process as well.
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