大直径集束式潜孔锤反循环钻进技术研究

针对大直径集束式潜孔锤反循环钻进试验发现的问题，选型配套了大规格双壁钻杆，改进设计了大直径集束式反循环潜孔锤和孔口密封装置等关键装置。依托某大直径工程项目进行了现场试验，结果显示:大直径集束式潜孔锤反循环钻进平均机械钻速3.41 m/h，与同条件下大直径牙轮钻头正循环钻进相比，效率提高了3.2倍；与原大直径集束式潜孔锤反循环钻进相比，效率提高了60%。

Research on reverse circulation drilling technique of large-diameter cluster DTH hammer

For the problem of large diameter cluster DTH hammer reverse circulation drilling tests found，large size double wall drill pipes were selected，and the design of the large diameter cluster of reverse circulation DTH hammer and port seal device were improved. The field test was carried out based on a large diameter project. Results show that，the average mechanical drilling speed of the reverse circulation drilling was 3.41 m/h. Compared with large diameter roller bit drilling under the same conditions，the efficiency is improved by 3.2 times，the efficiency is improved by 60% compared with the original large diameter cluster DTH hammer reverse circulation drilling.