METHOD OF PREVENTION OF DEVELOPMENT ENTRIES IN COAL BED AREAS Russian patent published in 2008 - IPC E21C41/16 

FIELD: mining.

SUBSTANCE: method of prevention of development entries in coal bed areas at development of coal beds by means of mechanised complexes consists in performing development entries 1, arranging outpost columns of mineral, then loosening of mineral bed in wall of working. Loosening is performed by means of drilling bores 2, 3 simultaneously with driving of development entries. The depth of mineral bed loosening from the side of driven area from the entry and from the side of massif is assumed as exceeding the depth of spread of intensive destruction of mineral bed in the edge zone. Bores 2, 3 are arranged in a staggered order along the thickness of a developed bed and have diameters equal to ½ of developed bed thickness. Soft cases are installed into bores 2, 3; then compressed air is supplied into soft cases till their strutting off in walls of bores 2, 3. When the column is reversed driven, soft cases are extracted before the line of a mining face 5 into conveyer 1 and ventilation 6 entries. Behind face support 7 of the mining face 5 "П"-shaped supports 9 are laid on the floor of the bed where a long face interfaces with conveyer entry 1; pneumatic tanks 8 are assembled in the supports; and a compressed air is supplied into tanks strutting off supports 9 and pneumatic tanks 8 between the top and floor of the bed. After descent of rock under the influence of the rock pressure and after walls of "П"-shaped supports 9 have contacted with floor, pneumatic tanks 8 are decompressed and taken out into conveyer entry 1.

EFFECT: invention facilitates increased efficiency of protection of development entries and also decreases costs for development entries maintenance at their reuse.

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