SU1205643A1 - Blasting method for overburden operations at opencast mining of seam deposits of useful minerals - Google Patents

Description

one

The invention relates to the mining industry, in particular to methods for blasting operations in the open pit mining of mineral deposits.

The aim of the invention is to increase the volume of discharge of rocks into the generated space due to the redistribution of the explosion energy in the discharged block.

The drawing shows schematically a discharged block with the location of wells, with the combination of development, ala of rocks after exploding, where 1 is the boundary of the dumps before the Explosion; 2 - boundary of dumps after vzrysh in a block pulling; 3 - boundary of I and P zones 4 - lines of drilling direction.

The method is carried out as follows.

From the condition of equality of volume V

“Rocks, the zone of the constant divergence zone and volume V,

being in

fishing, determined by the width of the first zone

taking into account the coefficient of loosening,

which varies within i, 2b5.

The volume of the first zone is equal to

A, -t- B,

I

HL;

V. - -

H L;

V, (A, H + J H) -L,

where A is the width of the Gth zone;

H is the height of the block being exploded; C - horizontal distance

the slope of the ledge; L is the block length; B - width of the 1st zone at the bottom.

205641. 2

The volume of rock located in the zone of constant dumps is equal to Ah,

V

TO

L

where a h.

-Work width;

- average camber height in the zone of a constant dump;

K - coefficient of loosening of rocks.

CA, H + o, 5c-H) -L,

from here

A ,, 5C.

An example. Cut conditions: the width of the first zone is 20-23 m with the parameters m; h 23 m; H ZOM; With 6m.

The first row of wells I and zones are drilled off a ledge at a distance of 10 m, which is for wells with a diameter of 220 mm 46D. The second row is at a distance of 2.5 m from the first. The third row of wells of the 1st zone is drilled at a distance of 7.5 m from the second row. In all three rows of the T-zone, the distance between the wells is 3 m, which is 0.5 between the wells in the second zone.

The first row of wells of zone II is drilled at a distance of 6 m from the last row of the 1st zone with a distance between wells of 6 m. The remaining rows of wells are drilled along a grid of m.

The explosion of the block is carried out in the order of the blasting pattern, with the first and second rows of the T-th zone being instantly exploded, and the third row - with a deceleration of 75 ms in relation to them. The rest of the rows are boiled up with an equal delay of 25 ms.

Compiled by A. Gnuskin Editor A. Klyukina Tehred I.Popovich Proofreader 0. Lugova

Order 6974/2 Circulation 432 Subscription

VNIIPI State Committee. the USSR

for inventions and discoveries I 3035, Moscow, Zh-35, - Raushsk nab. 4/5

Production and printing company, Uzhgorod, st. Design,

Claims (1)

EXPLOSIVE METHOD FOR EXPLOSION WORKS DURING OPEN DEVELOPMENT OF LAYOUTS OF USEFUL FOSSILS, including drilling wells in an explosive block with their arrangement in parallel rows, loading wells with explosive material, their short-lived ignition, which is slow-burning and excreted in mined space. in order to increase the volume of rock discharge into the worked out space due to the redistribution of the energy of the explosion, the blasting unit is divided into two eons, the width of A of the first zone is determined by the formula A - ήώ. ₀ , ₅ s, where A is the width of the entry; h ₍ = average camber height in the permanent dump area; H is the height of the blasted block; K is the coefficient of loosening of rocks; C is the horizontal position of the ledge. The distance between the wells in the rows of the first zone is taken equal to 0, ΙΟ, 6 the distance between the wells in the rows of the second zone, while the rows of wells of the first zone are placed from the edge of the ledge at a distance of 30-60 well diameters, and the first two rows explode instantly. >