关键词: 抽采钻孔, 钻孔深度, 负压分布

Abstract: It has a close relationship between gas flowing and the pressure in coal seam drilling, and the pressure distribution along coal seam drilling at different depths is not same because of resistance when the gas flowing. in order to get the relationship between pressure and the drilling depths, This article discussed the loss energy when gas flowing from the fluid dynamics and kinetic energy conservation law, and get the conclusion that the drainage pressure along coal seam drilling has a little change with the depths, and given a reasonable depth of borehole drilling that has guiding significance for the design of coal mine methane drainage drilling depth at the end of the article section.

Key words: borehole, drilling depth, negative pressure distribution