套管的作用是加固井壁、隔绝水层等.在钻进过程中往往发生套管柱下跑或断脱事故.有时在一个钻孔中,套管柱竟断脱数节,我队每年耗于处理套管事故的时间约占钻进工作时间的5%.经分析,套管断脱的基本原因有:1.套管柱未下到基岩盘,在超径钻孔中呈悬吊状态,钻进时受到钻杆柱的碰撞而发生回扣脱落.2.套管与接箍丝扣连接不合规格.套管 The role of the casing is to reinforce the wall, the water layer isolation, etc. In the drilling process often occurs under the casing string running or broken accident.Sometimes in a hole, the casing string actually off a few sections, my team each year The time spent on casing accident was about 5% of the drilling time.The basic reasons for the casing breakage were as follows: 1. The casing string did not go down to the bedrock, Hanging state, when drilling by the drill string collision and rebound off .2 casing and collar threaded connection non-compliant casing