METHOD FOR PREPARATION OF ORE BODY FOR MINING Russian patent published in 1995 - IPC

FIELD: mining industry. SUBSTANCE: method for preparation of ore body for mining includes drilling and casing of wells, formation of hollows from wells and supply of concrete mix. When preparing diamond pipes for mining, wells are drilled in the internal area of pipe boundary with their bottoms located on the contact with enclosing rocks. Wells are drilled vertical or inclined, with their zenith angles set depending on angle of pipe taper. Hollows are formed with cross-section in form of two triangles whose common side is located in plane of contact of overlying rocks with crater part of pipe with deepening into unbroken kimberlite material. Upper part of hollow is confined by surfaces, from external side, coinciding with contour of dome of natural equilibrium, and, from internal side, directed at acute angle to pipe central axis. Hollows during formation are connected with one another to form circular working, and concrete shoe is made is made by supply of concrete mix. Shoe is drilled out from wells whose bottom are located in enclosing rocks. Wells are additionally cased and drill pipe-borehole annulus and drill pipe-casing annulus are cemented. Overlying rocks are consolidated within contour of natural equilibrium dome by injection of bonding material. EFFECT: higher efficiency. 2 cl, 5 dwg