METHOD FOR EXTRACTING THICK FLAT-LYING COAL BEDS Russian patent published in 2006 - IPC E21C41/18 

FIELD: mining industry, possible use during underground extraction of thick flat-lying coal beds.

SUBSTANCE: method includes dividing coal bed on two layers, processed by faces, equipped with mechanized supports, advance processing of upper layer, processing of lower layer while leaving a coal cluster between layers. Depth of zone of destroyed coal, forming in coal massif, positioned below upper layer, under effect from supporting pressure, occurring in front of upper layer face, is determined. Between upper and lower layers a coal cluster is left with thickness not less than a total of aforementioned depth of destroyed coal zone and minimally allowed thickness of coal cluster not destroyed by supporting pressure, left between upper and lower coal layers, during descent of which its cave-in occurs in bottom space of face.

EFFECT: prevented spontaneous cave-ins of ceiling rock in bottom space of lower layer faces.

2 dwg