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China 's coal mining efforts and increasing mining depth , high - gas coal mine gas outburst gradually increased . How to take effective measures to achieve safe and efficient mining become an important task placed in front of the mining workers . The gas pressure is the iconic parameter identification of coal and gas outburst , outburst the main basis for a regional breakdown . Outburst in the new mining area , a new level must test the gas pressure , which is the normal work of industry and regulatory requirements, coal and gas prominent provisions \Gas pressure not only reflects the size of the final gas pressure , and stress testing process also reveals a dynamic gas flow . In this paper, Horner approximation and coal seam gas flow theory as a hypothetical basis , systematic exposition of the coal seam gas flow patterns and drilling gas radial flow theory . Combined with radial holes around the gas pressure and pressure recovery curve changes , new seam permeability coefficient calculation method , the degree of difficulty of the seam drainage reaction . The study results show that , in practical applications , only the measurement time is long enough to completely stabilize the case of measurement results in order to make the calculated results and the actual results sufficiently close . Through the use of the method of time series analysis , the establishment of the pressure recovery curve model, based on the mathematical theory of knowledge and analysis of coal seam gas flow patterns , combined with borehole gas pressure recovery curve to obtain the new method of calculation seam permeability coefficient . In this paper, a new method to calculate the seam permeability coefficient actual inspection applications , the results show that this method of calculation the seam permeability coefficient and drilling attenuation coefficient with speed , reliability, accuracy characteristics , so that it can better reflect the seam drainage , and to achieve the desired effect of gas drainage .
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