METHOD FOR INITIATION OF DEEP-HOLE EXPLOSIVE CHARGES Russian patent published in 1999 - IPC

FIELD: blasting operations in mining industry, applicable for blast breaking of rocks at mining or construction. SUBSTANCE: the method consists in placement of blasting cartridges in the blast hole in the form of alternating straight-line sections and circular loops and supply of initial pulse through detonating cords. The loops are placed in the vertical plane near the outside (relative to the rock mass to be broken) wall of the charge; each loop has a diameter equal to 0.5 of the charge diameter, with the distance between them equal to the charge diameter. EFFECT: enhanced quality of crushing or rocks due to superposition of detonation waves moving in direction of high wall. 1 tbl