DEEP-HOLE CONTOUR CHARGE Russian patent published in 2000 - IPC

FIELD: mining art, in particular, blasting operations at extraction of mineral resources by blasting. SUBSTANCE: deep-hole contour charge has explosive cartridges that are side-fastened on a wooden insert, adjoin the hole walls and oriented in the axis of the contour row of charges, porous stemming of organic origin is used as internal stemming between the explosive cartridges and above the contour charge, and a damper stemming consisting of inert and porous parts is positioned in the bottom part of the deep-hole. EFFECT: redistributed energy of explosion, considerably reduced effect of explosion on the mass behind the contour and on the bench bottom; reduced cost and enhanced output of mining. 2 dwg