SU1640515A1 - Method for breaking ore - Google Patents

Abstract

The invention relates to mining and can be used in underground mining of mineral deposits. The purpose of the invention is to increase the sustainability of the workings at the bottom of the block by reducing the seismic effect of the explosion of explosives charges on them. At the bottom of the block are transitions of auxiliary workings. Drilling fans are drilled from the excavation in the bottom of the block. In each well, two independent explosive charges are formed. The latter are separated by an inert baffle. All charges B are blown in one step in the following sequence: first all charges of explosives from the bottom of the block in the direction away from the compensation space are blown up, then in the same sequence blown charges of explosives after an inert gap. The time of slowing down the blasting of downhole charges of explosives with respect to the wellhead is chosen not less than the value, according to the difference of the expression 21 10. w. q / yJ C, where w is the line of least resistance, m; P - specific consumption of explosives for blasting, kg / m, p - mass density, kg / m; c is the velocity of the longitudinal wave, m / s 2 or

Description

The invention relates to mining and can be used in underground mining of mineral deposits.

The purpose of the invention is to increase the sustainability of the workings of the bottom of the block by reducing the seismic effect of the explosion of explosive charges on them.

Figure 1 shows a part of the block, a vertical projection; figure 2 - section aa in figure 1.

The method is carried out as follows.

From the scraper mine 1, niches 2, ducts 3, drilling chamber 4 are passed. The ore massif is drilled from the drilling chamber with 4 fans I – VI deep boreholes 5 in one step. Initially, in layers, with a millisecond slowdown, starting with fan 1., i.e. from collapse, and ending with fan VI, they explode charges 6, which are closer to the bottom of the block, thus forming a hook or screening gap between

the bottom of the block and the remaining unbroken ore massif, which is then in the same order (layer by layer, with a millisecond slowdown, starting with fan 1 and ending with fan VI), are charged with charges 7 located on the other side of the inverse intervals 8

The time of slowing down the blasting of downhole charges of explosives relative to the wellhead is chosen not less than the value determined from the expression

g 27 10

,four. w q

p with

where 27.10 is a constant coefficient obtained experimentally;

w is the line of least resistance, m;

Q - specific consumption of explosives for blasting, kg / m-5;

p is the density of the array, kg / m3;

c is the velocity of the longitudinal wave in the array, m / s.

Claims (1)

Invention Formula The method of ore blasting, which includes the formation of a compensation space, the excavation of workings in the bottom of the block, I- 0 five 0 drilling downhole fans, charging them with explosives and sequentially blasting downhole fans into the compensation space, so that, in order to increase the stability of the workings in the bottom of the block by reducing the seismic effect explosions of explosives in them, in each well, the charges are divided into two charges separated from each other by an inert gap, and first of all in each fan the charges explode from the bottom of the block, then from the bottom of their faces separated from first inert spacing, and the interval of deceleration of blasting of charges from the bottom of wells in each fan relative to charges from the bottom of the blocks is chosen not less than the value determined from the expression g 27 10 A w; q (p with 25 where w is the line of least resistance, m, q is the specific consumption of explosives for blasting, kg / m, p is the density of the array, kg / m3 c is the velocity of the longitudinal wave, m / s / ь Phage 1 Phage. 2