Technology and Application of Directional Drilling with Mud Pulse Measurement with Drilling in High Level Directional Drilling of Roof

According to the slow drilling speed, small diameter, low reaming efficiency, easy damage of drilling equipment and other disadvantages of the high level directional borehole in roof, directional drilling with mud pulse measurement with drilling technology for constructing high-level directional drilling of roof was proposed. We developed key drilling technologies, such as mud pulse wireless transmission technology, compound directional drilling technology, dynamic secondary rotary reaming technology of orifice, developed and equipped key drilling equipment such as directional drilling rig, mine-used mud pulse measurement system, mud pump, four-stage screw motor, high-strength high toughness drill rod and directional drill bit to form a complete set of technology and equipment. The field test was carried out in Sihe Mine 5304 working face, the results show that 12 high location directional borehole of roof were successfully completed with the maximum hole depth of 480 m, total length of 4 929 m, hole forming rate of 91.7%, and the mechanical drilling speed is increased by more than 30%, and the construction effect of high directional drilling in roof is greatly improved.