针对顶板高位大直径定向钻孔分级扩孔综合效率低、钻具安全性差等问题，开发了双级双速扩孔方法，研制了双级双速扩孔钻具，包括直螺杆马达、一级钻头与二级钻头。运用等碎岩比功理论开展双级双速扩孔分级研究，确定了一级钻头与二级钻头切削分界面直径为157 mm，一级钻头外径为165～172 mm。分别从壳体、马达动力总成、万向轴总成、传动轴总成与连接模块等方面开展设计研究，研制了105 mm双级双速螺杆马达。采用参数化设计方法，配套研制了多种规格的一级钻头与二级钻头。现场试验结果表明，双级双速扩孔技术可将高位定向钻孔直径由120 mm一次增扩至200 mm，综合钻进效率得到提高，钻孔瓦斯抽采效果良好，为工作面采动卸压瓦斯高效抽采定向长钻孔快速成孔提供了新方法。

Aiming at the problems of low comprehensive efficiency and poor safety of drilling tools, a two-stage and two-speed reaming method is developed. A two-stage and two-speed reaming drilling tool is developed, including a straight screw motor, a first-stage bit and a second-stage bit. Based on the theory of specific work of equal broken rock, the study of reaming classification is carried out. The cutting boundary diameter between the first and second drill bits is 157 mm, and the outer diameter of the first drill bit is 165～172 mm. The design and research are carried out from the aspects of shell, motor power assembly, cardan shaft assembly, transmission shaft assembly and connection module, and the 105 mm two-stage and two-speed screw motor is developed. By means of parametric design, various specifications of first and second stage bits are developed. The field test results show that the two-stage and two-speed reaming technology can increase the diameter of high-level directional drilling from [JP3]120 mm to 200 mm at one time, improve the comprehensive drilling efficiency, and provide a new method for the quick hole formation of directional long drilling with high-efficiency gas drainage under pressure relief.

0 引言

1 双级双速扩孔技术原理

2 扩孔分级原理

3 双级双速螺杆马达研制

   3.1 马达本体设计

   3.2 马达总成设计

   3.3 万向轴总成选用

   3.4 传动轴总成设计

   3.5 连接模块设计

4 扩孔钻头研制

5 现场试验与效果分析

6 结论