Bending Drilling Construction Technology of Gas Drainage in Soft Coal Seam Through Beds Hole

In order to enhance the gas drainage effects in low permeability coal seam, according to the coal seam characteristic in Huainan coal mining area, the deflecting technology was used in through beds hole to extend the length of coal and rock hole through bending drilling trajectory in coal hole section to enhance the effect of gas drainage, and the maximum bending strength is up to 2°/m in coal hole section. and the coal hole length was increased 2.1 times compared to conventional drilling length.