EXPLOSIVE HOLLOW CHARGE Russian patent published in 2009 - IPC F42D3/00 F42B1/28 

FIELD: blasting jobs.

SUBSTANCE: invention relates to blasting job and can be used for repeated crushing of off-size rock pieces in open-and closed-cut workings, destructing construction sites, metallurgy wastes, and in various blasting jobs related with the blast directional effects. The proposed hollow charge comprises an encapsulated explosive, shaped enclosure arranged inside a shaped recess, and an initiator. The charge enclosure represents a polymer container with its bottom representing several parallel, elongated shaped recesses. The shaped recess height-to-shaped recess width ratio varies from 0.85 to 1.9. The said recesses either abut on each other or are separated by the bottom flat sections with the bottom width making 0.3 to 0.4 of the said shaped recess. The opposite walls of the polymer container, at the level of line blast initiators, feature through holes. Used initiators represent equal-length line blast initiators initiating, at a time, explosive upper layers above the rib passing over and above every shaped recess apex at a distance not exceeding the shaped recess height. The said initiators are covers by a layer of explosive with its height making, at least, half the explosive detonator critical diametre. The line initiator ends are brought out outside. The polymer container top, above the explosive layer, accommodates an inertial material cover or tamping. The hollow charge is arranged directly on the off-size rock piece or at a distance therefrom not exceeding four heights of the shaped recess.

EFFECT: higher efficiency of crushing, lower costs, expanded range of hollow charges used.

6 cl, 8 dwg, 1 ex