SU891915A1 - Method of explosion-breaking of rock - Google Patents

Description

(54) METHOD FOR EXPLOSIVE SEAL OF ROCKS

I

The invention relates to blasting and can be used in the mining, construction and other industries.

Methods for blasting rock are known, which consist in the fact that axial cavities are created in the charging chamber along the length of the charge and the explosive is placed between the cavities and the walls of the well. Cavities are usually enclosed in shells made of various materials 1.

There is a method in which the axial cavity is arranged symmetrically to the axis of rotation for the entire charge length. The explosive is placed in such a way that the charge in the cross section has the shape of a ring. The axial cavity is separated from the explosive by the shell 2-.

The disadvantage of this method is the low efficiency of using explosive energy for crushing rocks and the effect of an explosion on the emission.

The purpose of the invention is to increase the explosive energy utilization rate.

This goal is achieved by the fact that the charge is created with the ratio of the diameter of the shell to the outer diameter of the layer of explosive in the range of 0.3-0.6 when crushing rocks of 0.5-0.75 during outburst, and the time of dynamic stability of the shell after blasting is determined from the ratio.

t 1,57-,

D

ev

where dj.g is the outer diameter of the ring charge;

 - detonation speed of explosive.

FIG. 1 is a dependency graph; in fig. 2 - section of charge of explosives of continuous construction; in fig. 3 is a section of the charge of explosives of a ring structure without a shell; in fig. 4 - the same with the shell.

FIG. 2-4 marked: BB 1, detonating cord 2, cavity 3, the inner sheath 4.

The breaking of rocks is carried out as follows.

Depending on the geological conditions, an annular charge is prepared by grinding or ejection. For this, a hollow shell is placed in the drilled hole (hole or hole).

Then the space between the shell of the axial cavity and the borehole wall (hole

or development) fall asleep explosives. The gunman is prepared before or after the formation of a ring-shaped charge in the well. Well blasting is done in the usual way.

The technical and economic efficiency of the proposed method is based on the fact that at certain ratios of the inner and outer diameters of the explosive ring and the presence of a shell of a certain strength, it is possible to control the fractional part in the process of breaking stress waves and gaseous explosion products that enhance blasting (crushing) or piston action BB

Claims (2)

1. Physics of the explosion. M., "Science, 1975, 236237 2. The patent of France No. 2042801, cl. F 42 D 1/00, 1974 (prototype). Phage.1 FIG. 2 Fi.Z