(一)前言在流砂层中钻探,一般要比在基岩中钻探困难得多,主要是流砂层,容易坍孔,不易固住孔壁,由于坍孔,流砂湧砂又易造成埋钻、卡钻等事故,大大地影响生产进度,同时钻探工人们付出的劳动强度较高,因此在钻探术语上称“流砂层为钻探的大敌”。在矿山钻探中碰到流砂层的机会较少,要求也较低、 (I) Preface Drilling in runoff sand is generally much more difficult than drilling in bedrock, and is mainly runoff. It is easy to collapse the hole and is not easy to hold the hole wall. Buried sand, Drilling and other accidents, greatly affect the progress of production, while drillers pay a higher labor intensity, so drilling terms, said “quicksand is the enemy of drilling.” There is less chance of encountering sand flow in mine drilling and the requirements are also lower,