Abstract：In order to prevent gas disasters and accidents, to improve the drilling efficiency, and to reduce the number of drilling and coal seam outburst elimination rate, PD material, cement mortar, and polyurethane material were used as the drilling hole sealing material for test at the scene of a coal mine. The gas extraction concentration and change of all kinds of traffic data of boreholes were analyzed after the hole sealing with three kinds of materials. Practice showed that the PD new sealing material has the advantages of both the permeability and compactness of cement mortar, as well as the swelling of polyurethane materials, etc. And also it can promote the material around the borehole fissure permeability, improve the sealing effect, and has good resistance to decay. The technology has obtained a good extraction effect, and make the gas volume fraction increased nearly 70%, therefore, it has good practical application value.

Keyword：gas extraction;borehole;PD material;sealing holes;extraction concentration;