CONTOUR CHARGE WITH THRUST STEMMING Russian patent published in 2007 - IPC F42D1/02 F42D1/08 

FIELD: mining industry, in particular, mining of hard rocks, when there is a necessity to reduce the effect of blasting operations on the contour mass installed to the extreme position of the flank of an opencast.

SUBSTANCE: the contour charge with a thrust stemming includes a damper interlayer in the bottom part, it consists of fine-fractional inert and compressible combustion materials, a double string of single explosive cartridges with a mass of 200 g positioned near the borehole walls in the axis of orientation of the contour charge, and a triple arrangement of the explosive cartridges in the bottom part of the charge, as well as a combination of an inner porous stemming and an upper stemming. The damper interlayer of compressible combustion material in the bottom part and the inner porous stemming the made of foamed polystyrene, and the strings of cartridges in the lower part are connected by a spacer in the height of the triple cartridges, and the upper stemming is made in the form of a metal thrust stemming.

EFFECT: simplified construction of the contour charge and enhanced efficiency of action of detonation products due to prolonged locking in the borehole.

4 dwg