METHOD TO APPLY ACTION TO COAL BED Russian patent published in 2006 - IPC E21F7/00 

FIELD: mining, particularly coal mining industry, namely to act upon coal bed.

SUBSTANCE: method involves drilling borehole; casing the borehole; injecting liquid into the borehole through hole annuity defined by casing pipe and generator body in static mode up to borehole crack system filling with liquid; applying impulse action to liquid column with the use of generator arranged at casing pipe head ; communicating the borehole with degassing pipeline. Impulse action is applied by gas jets ejected from gas generator. The gas jets provide threshold of density and wave fronts in liquid column. Crack system is created by applying compression wave impulses under 100-150 MPa pressure to coal beds with coal hardness of f=0.5-2 s, therein time of compression wave impulse application is 0.07-0.13 s in the case of predetermined cracking radius equal to 10 m or 0.13-0.26 s in the case of cracking radius equal to 20 m.

EFFECT: increased rate of underground coal bed degassing, increased load to be applied to mining face, increased safety due to gas, dust and coal and gas outburst control.

2 dwg