METHOD OF EXPLOSIVE DESTRUCTION OF LARGE-SIZED BLOCKS AND SHAPED CHARGE Russian patent published in 1995 - IPC

FIELD: destruction of large (outsized) lode rocks, building blocks, salvaging of waste of metallurgical process, scrap and emergency discharges of metal. SUBSTANCE: blast-holes are formed by shaped-charges. Charges are placed at a distance of 0.1 to 4.0 charge diameters from the surface of the block to be destroyed, positioned in layers in parallel with the side free surface of the block space. Blast-holes are filled with explosive composition. Blast-holes are blasted by rows, beginning from the free surface, with provision of time delay of blast of each subsequent row sufficient for the process of destruction of the previous row. The difference in time of blast in a row does not exceed R/2C, where C-sound velocity in block material; R-distance between blast-holes in a row. The distance from the free surface to the first row, makes up 2 to 10 diameters of the formed blast-hole. The shaped charge contains a charge of explosive 1 with a cylindrical part, having height H_c= 0,8 d_в/tgα, and turning into a truncated cone. Lining of shaped recess 2 has opening of cone equal to 2α=80-100 deg. base diameter 0.85 to 0.95 of diameter of the cylindrical part, and thickness equal to 0,01-0,03/d_вδ_с/δ_m.. Lining can be made of steel or aluminium. EFFECT: facilitated procedure. 4 cl, 2 dwg