In Hu Di Mine of Jincheng Anthracite Mining Group, the coal-rock interface at the floor of No. 3 coal seam experienced hole collapse. This led to the accumulation of large pieces of coal and gangue at this location, resulting in high pressure inside the hole, drill pipe jamming, pipe squeezing, and other issues, making normal construction impossible.In response to this problem, both the bottom - hole device and the drill pipes were changed to a structure with spiral grooves. When passing through the coal - rock interface and encountering soft coal or lump coal, the hole collapse problem can be solved by rotary flushing, ensuring normal construction. There is no need for reaming operations with ordinary drills. This technology can cover both the mining face and the roadway simultaneously, achieving good gas drainage effects. From April 22, 2018, to September 2, 2018, a total of 8 boreholes were drilled in the drill site 2 kilometers to the left of the 1305 bottom gas drainage roadway. The total footage was 7394m, the footage of coal - bearing boreholes was 3635m, and the proportion of coal - bearing boreholes was 49.16%. The average single - hole footage was 57m. On September 15, 2018, the measured gas extraction volume was 2.45m³/min, and the flow rate per 100 meters was 0.067.