METHOD FOR BLASTING OF BEHCHES UNDER SHELTER AND MECHANICAL DEVICE FOR ITS REALIZATION Russian patent published in 2007 - IPC F42D1/08 F42D3/04 F42D5/05 

FIELD: mining industry, in particular, mining of hard rocks in hindered conditions when it is necessary to prevent scattering of the blasted rock mass.

SUBSTANCE: the mechanical device for long-term locking of detonation products has a cylinder with an axial cavity and a tapered expansion. The tapered expansions are made on both-ends of the cylinder and at least three slots are made in each of them. A spacer cone is inserted in the lower tapered expansion, it is coupled to a thick-walled tube freely passing through the axial duct of the tapered plug inserted in the upper tapered expansion. The tapered plug is additionally provided with a recess closed with a hinged cover and with an installation loop with a flexible coupling. The method for blasting of benches under a shelter consists in drilling of blast holes, their charging, tamping, sheltering of the bulk to be blasted, blasting of the rocks and removal of the shelter. Tamping of the holes is made by installation of mechanical devices for a long-term locking of the detonation products and their preliminary wedging in the hole. The mechanical devices for a long-term locking of the detonation products are lowered in the hole down to the required lever and installed their. The initiating pulse conductor is placed in the recess in the tapered plug of the mechanical devices and closed with the cover. After that the shelter in the form of a mat composed of inter connected automobile tires is placed on the high wall and the bench surface, and fastened by the anchors installed in shallow holes with the aid of ropes and thin chains. Part of the mat (1-2 types) should remain on the bench bottom. After that the mechanical devices for a long-term locking of the detonation products are connected to the shelter by a flexible coupling, the conductors of the initiating pulse are extracted from them, the blasting network is installed above the shelter, and the sheltered bench is blasted. After the blast the shelter is removed with the aid of a bulldozer for the ropes or chains removed from the anchors, the mechanical devices for complete locking of the detonation products are removed at the same time.

EFFECT: provided breaking of rocks without scattering of pieces to the high wall slope with a long-term locking of the detonation products in the charge cavity.

5 cl, 4 dwg