Research on safe and efficient drilling technology of soft outburst coal seam

Abstract

In soft coal bedding drilling hard into the problem of hole, based on the drilling of coal in the process of motion, from two aspects to improve the traditional drilling technology, selection of high power, large torque drill and selecting reasonable parameters of drilling tools and better way of powder, formed a “high power drill, shallow blade spiral drill pipe, wind pressure in the wind” of the construction process. The field application test was carried out in Xinxin Coal Mine of Yunnan Province, and the test results show that the average monthly footage of drilling rig is 8000 m/rig•month. The average depth is 137m, the primary pore formation rate reaches 90%. Compared with the original drilling technology, the new technology increases the average hole depth by 12%∼70%, the drilling efficiency by 30%∼46%, the extraction concentration by more than one time, and the single hole extraction amount by 33.6%. The drilling technology of soft outburst coal seam has improved the drilling efficiency and realized the full coverage of gas drainage in working face, which is worthy of reference and reference in soft coal seam mine.