Analysis of Influencing Factors on Effective Radius of Drilling Gas Drainage

According to the theory of gas flow in coal seams, and according to drainage standard and the other relevant laws and regulations, derived the calculating equation of efficient radium of drilling hole gas extracting in drill holes in coal seam and drill holes along seam. Efficient radium of drilling hole gas extracting was calculated, combining with field practice of coal seam named 1 in Xinji No. 2 coal mine, the comparison with efficient radium of drilling hole gas extracting tested in field. Analysis on influencing factors of efficient radium of drilling hole gas extracting, and obtain the influence law on the efficient radium of drilling hole gas extracting.