Drilling technology of long hole using for discharging gas from coal seams
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Graphical Abstract
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Abstract
It is introduced that the test of long drilling hole using for discharging gas from coal seams. Executed 3 hole using directional drilling technology,one drilling hole depth is up to 509.03 m,which is the longest drilling hole in coal seams,average sheet drilling speed is up to 24.4 m/h.Discharge of all these hole is up to 2.0~2.5 m3/min.
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