Sectionalized Hybrid Hole-sealing Technology in Downward Measuring Pressure Drilling Holes of Little Inclination

On the basis of reviewing literatures related to coal seam gas pressure test,the difficulties and shortcomings of sealing in the little inclination downward pressure measuring holes were summarized and analyzed.Combining with the advantages of traditional sealing methods and making improvements,a sealing method,sectionalized hybrid hole-sealing technology,that injecting polyurethane and cement slurry sectionally was put forward,which was applied in field and achieved good affects.