Study on efficiency verification of strip in gas pre-drainage coal roadways based on long-distance sealed coring

Regional gas drainage effect test is an important part of the four in one comprehensive outburst prevention work. Sihe Coal Mine uses residual gas content as an indicator of the effectiveness of gas outburst prevention measures in pre-drainage roadways, and uses conventional coring to measure gas content to evaluate gas drainage effect by sections. The effectiveness test method has problems such as small evaluation range, large deviation of test point trajectory, and cross operation of tunneling and effectiveness inspection and so on. Based on the study of long-distance sealed coring technology in underground Coal Mine, a fast test method for gas pre-drainage effect of coal roadway strip based on long-distance sealed coring is proposed, and the gas pre-drainage coal road strip in eastern working face is selected for test.The test results of Sihe Coal Mine show that the gas content measured by long-distance sealed coring is 1.26 ~ 1.71 times of that measured by conventional coring, and the range of one-time efficiency verification of strip gas pre drainage in coal roadway is expanded from 90 m to 390 m. The research shows that the efficiency verification method of strip gas pre drainage in coal roadway based on long-distance sealed coring is feasible. This method realizes accurate fixed-point, long-distance and sealed coring of coal seam drilling, improves the accuracy of gas content measurement results, greatly expands the one-time evaluation range of regional gas pre drainage effect, reduces the cross operation of production and effective detection in heading face, and promotes the balance of “pumping, driving and mining” in mine production.