大直径扩孔用反循环钻进双壁钻具研制

煤矿井下大直径钻孔扩孔施工时存在钻进效率低、排渣困难、钻具匹配性不佳等问题,而采用集束式潜孔锤反循环钻进技术可较好地解决该问题,为此研制了空气反循环钻进用双壁钻具,重点介绍了双壁钻杆和双通道气水龙头的结构、关键技术参数及性能特点,并进行了现场试验。结果表明,该套钻具结构设计合理,能够满足集束式潜孔锤反循环钻进工艺要求,为后续在煤矿井下推广应用提供了实验依据。

Development on Dual-wall Drilling Tool for Reverse Circulation Drilling and Large-diameter Reaming

There are some problems in the large diameter drilling and reaming construction in coal mine, such as low drilling efficiency, difficult slag removal, and insufficient matching of drilling tools,etc., which can be solved by using cluster down the hole hammer reverse circulation drilling technology.Therefore,dual-wall drilling tool for air reverse circulation drilling was developed. The structure,key technical parameters and performance characteristics of double wall drilling pipe and double channel air faucet were mainly introduced. Field tests were carried out. The results show that the structure design of the drilling tool is reasonable,which can meet the requirements of the reverse circulation drilling technology of the cluster down the hole hammer,and provide the experimental basis for the subsequent application in coal mine.