METHOD OF PREPARING TURPIN CHARGE IN BOREHOLE Russian patent published in 1999 - IPC

FIELD: explosives. SUBSTANCE: liquid petroleum product is poured into hose of elastic film material placed in vertical down-hole, after which into hose successively placed are hollow base-course spheres, structure formed by two perforated mutually parallel discs attached to ends of rods or pipes with lengths at least 1.5 down-hole diameter. Then hollow top spheres, above structure, and base-course spheres are descended to bring base-course spheres into contact with petroleum product and hose end is tightly connected with flexible dinitrogen tetroxide-supply pipe. Dinitrogen tetroxide is poured in and released gas comes out through this pipe into isolated vessel or directed to neutralization zone. Resulting charge is insulated by part of stemming, dinitrogen tetroxide-supply pipe is washed, while wash water is poured off into part of hose separated from the charge. Top part of hose is collapsed and simultaneously withdrawal of gas from hose is completed. Hose end is disconnected from flexible pipes, descended into hole head and stemming is completed. EFFECT: improved safety. 3 dwg