EXPLOSIVE COMPOSITION AND A METHOD OF PREPARING BOREHOLE CHARGE Russian patent published in 2003 - IPC

FIELD: explosives. SUBSTANCE: explosive composition intended for use in performing open-cut blasting operations comprises granulated explosive, namely granulite, grammonite, grammonal, granulotol, or their mixture and powdered explosive, namely ammonite, ammonal, diammon, or their mixture. Preparation of borehole charge comprises filling borehole with explosive mixture placed in cylindrical double-layer envelope consisting of inside and outside shells, the inside one being made from waterproof polymer material with diameter superior to borehole diameter and outside shell being made from polymer material or paper with diameter constituting 0.7-0.8 borehole diameter, the two shells having perforation along generating line. Fuse is attached to outer side of envelope and buried under envelope. EFFECT: increased efficiency of blasting operations. 7 cl, 3 dwg, 1 tbl