FORMATION METHOD OF COMPOUND BLAST Russian patent published in 2009 - IPC F42D1/08 

FIELD: explosive works.

SUBSTANCE: invention relates to mining engineering and can be used for hole loading when carrying out explosive works in mining engineering and construction. Formation method of compound blast provides for forming blast from water-resistant blasting powder in water-cut hole part, placing foamed polystyrene on the mirror of water displaced upward the hole, forming blast from non-water-resistant blasting powder on it and installing stem. Float, made from material with flotation properties and able to stand weight of blast obtained from non-water-resistant blasting powder, is placed on the mirror of water displaced upward the hole. Pieces of rocks or drill cuttings in tissular or polyethylene envelope with diametre not bigger than hole diametre are put onto the float.

EFFECT: reducing cost of explosive works production due to replacing expensive water-resistant blasting powder with cheaper non-water-resistant blasting powder and simplifying water-cut hole loading.

1 ex, 1 dwg