Study on New Borehole Sealing Device of Gas Drainage Borehole Along Seam

According to the complicated borehole sealing technique and high operation requirements existed in the available borehole sealing of the gas drainage, t he limited application scope, low gas drainage concentration, short effective gas drainage period of the borehole and other technical difficulties, a new borehole sealing device was applied to seal the borehole. The paper stated the borehole sealing principle of the new borehole sealing device. A comparison analysis was conducted on t he gas drainage concentrations between the new borehole sealing device + cement grout borehole sealing and the polyurethane + cement grout borehole sealing, the e xperiment results showed that with the application of the new borehole sealing device + cement grout borehole sealing, a single borehole sealing would only require 25 min and the polyurethane + cement grout borehole sealing would require 55 min for a single borehole. After 48 days of the borehole sealing and gas drainage, the aver age gas volume fraction of the new borehole sealing device + cement grout borehole sealing was about 33% and was higher than the gas volume fraction 4% drained fr om the polyurethane + cement grout sealing borehole. The borehole sealing technique of the new borehole sealing device was simple and after the borehole sealing, th e gas drainage concentration from the borehole would be high and the gas drainage time would be longer with a promotion and application value.