PROCEDURE FOR CHARGING DOWNWARD BLAST-HOLES IN PROCESS OF DRILLING AND BLASTING OF VERTICAL AND INCLINED MINE SHAFTS Russian patent published in 2001 - IPC

FIELD: mining industry. SUBSTANCE: high-power cartridge-free granulated explosives of class 1 are used in the capacity of explosives for charging downward blast-holes. In this case blast-holes are filled with highly concentrated solution of ammonium nitrate If dry blast-holes are charged first explosives are placed into blast- holes and then solution of highly concentrated ammonium nitrate is poured. If heavily flooded blast-holes are drilled first water is driven out of blast-holes by solution of ammonium nitrate which is fed by hose to bottom of blast-holes and then explosives are fed. EFFECT: enhanced efficiency of blasting operations while driving vertical and inclined mine shafts. 4 cl