巷道底板锚索孔钻进粉渣运移特征及现场试验

Study on migration characteristic of boring mud in roadway floor anchor wire hole and its field test

针对煤矿巷道底板锚索孔钻进困难的问题,分析了正反循环钻进过程中粉渣运移特征,得出"钻渣三区"的相互作用是制约底板锚索孔快速钻进的根本原因,并提出了泵吸反循环钻进可以有效防止"钻渣三区"的形成。利用固液流体力学原理,推导了冲洗液沿程水力损失及钻渣液上返流速的力学公式。根据现场实际,得出底板锚索孔泵吸反循环钻进时钻孔深度、泵的真空度及钻渣液的上返速度与钻渣体积含量之间的关系,结果表明泵吸反循环对底板锚索孔的快速钻进是可行的。研制了一套泵吸反循环钻进系统,实现了底板锚索孔钻进与排渣同时作业。现场试验表明,钻进深度5.6 m的底板锚索孔有效钻进时间可以控制在30 min内,解决了底板锚索孔深孔钻进的难题,净化了作业环境。

To solve the problem of drilling anchor holes into the roadway floor, migration characteristics of the reverse circulation drilling process of boring mud have been analyzed. The analysis has shown that the interaction of boring mud three-field is the primary cause of restricting floor anchor wire hole quickly drilling, and pump suction reverse circulation drilling that can be effectively prevented by boring mud three-field forming has been put forward. Using principles of solid-liquid fluid mechanics, mechanical formula of flushing fluid along hydraulic loss and slag drilling fluid return velocity has been successfully deduced. According to the field practice, the relationship between floor anchor wire hole pump suction reverse circulation drilling depth and drilling pump on vacuum degree and slag drilling fluid return velocity, and drilling slag volume content has been obtained. The result has shown that pump suction reverse circulation faster penetration of floor anchor hole is feasible. A set of pump suction reverse circulation drilling system has been developed, and floor anchor wire hole drilling and slag discharge operation at the same time have been realized. Field test has shown that effective time of drilling depth of 5.6 m floor anchor wire hole can be controlled within 30 min. The difficult problem of floor anchor wire hole deep hole drilling has been solved, and the work environment has been purified.