METHOD OF CHARGE DE-CONCENTRATION OF EXLOSIVE MATERIAL IN BOREHOLE Russian patent published in 2009 - IPC F42D1/02 F42D1/08 

FIELD: mining.

SUBSTANCE: invention refers to mining and can be implemented for charging boreholes at explosive operations. The method of de-concentration of charge of explosive material in a borehole consists in operations of forming lower portion of charge of explosive material in the borehole and in creating air interval above it by means of pneumatic borehole closure in form of a pressure tight ball-shaped chamber out of yielding material, which is introduced into the borehole and fixed at a specified depth. The pneumatic borehole closure is pumped with compressed air to a preset pressure with following sealing. Firing pins are installed in each part of charge of explosive material; further an explosive cord is arranged; an upper part of charge of explosive material is placed over the pneumatic borehole closure. Pumping and sealing are performed before introduction the closure into the borehole. A stop fixes the closure in the borehole at a preset depth; the stop is hung on a rope or is secured to a rod-shaped element. The pneumatic closure is introduced into the borehole under influence of gravitation forces.

EFFECT: invention facilitates reduction of labour intensiveness of method of boreholes charge; also it facilitates reduction of specific consumption of explosive material and its prime cost and improves quality of exploded rock.

5 cl, 1 ex, 2 dwg