The invention relates to a large
diameter bedding drill hole drainage goaf along a roof and upper corner gas technology. The large
diameter bedding drill hole drainage goaf along the roof and upper corner gas technology is characterized by comprising that steps that a high level
coal seam drilling field is constructed in a return
airway; (1), a crawler-type electric drilling
machine is used for constructing a long-distance large-
diameter drill hole in a drilling field in the mining direction separately forwards and backwards, after a drill tool is exited, a processed borehole protection sleevewith
sieve holes of a certain length is pushed into the large-diameter
drill hole to seal the large-diameter
drill hole; (2), in the main roadway or up a hill, the borehole protection sleeve with thesieve holes and the corresponding extraction pipeline are connected to extract gas in a goaf and upper corner. The amount of drilling construction is nearly 50% less than that of fan-shaped arrangement in a high level drilling field, the cost is low, the large-diameter
drill hole is constructed in a
coal seam, the construction speed is faster than rock stratum holes, part of the
coal is extractedduring the construction to save the cost of
coal mining, gas extraction flow rate is large, the borehole protection sleeve is arranged in the large-diameter drill hole, holes are not prone to collapsing, the gas extraction effect is better, and the overlimit function of gas in roadways is effectively eliminated.