Large-aperture directional blasting method and cartridge bag

Abstract

The invention belongs to the field of directional blasting of quarries, and particularly relates to a large-aperture directional blasting method and a cartridge bag. The large-aperture directional blasting method includes the steps that a cylindrical blast hole is adopted, the oval cylindrical cartridge bag with the oval cross section is placed in the cylindrical blast hole with the circle center of the cross section of the blast hole as the original point, a plurality of slits are formed in the two sides of the cartridge bag from top to bottom along the long axis of the oval cross section, the cross section of the cartridge bag meets an equation (please see the equation in the specification), the eccentricity e is equal to 0.92, the radial direction uncoupling coefficient K of the ratio of the cross section area of the blast hole to the cross section area of the cartridge bag is equal to 3.9, open-air emulsion explosive is arranged in the cartridge bag, and the linear density of the open-air emulsion explosive in the cylindrical blast hole is 8-10 kg / m. Presplitting blasting or smooth blasting can be formed without affecting the direction or the size of initial presplitting cracks, the quality of fracture surfaces is greatly improved, and the large-aperture directional blasting method is safe to use and can be used for open-air steps.

Description

technical field [0001] The invention belongs to the field of directional blasting in quarries, and in particular relates to a directional blasting method and a charge bag applied to large holes. Background technique [0002] The traditional pre-splitting blasting process has been used for nearly forty years. It uses hemp rope to bind the strip charge to two detonating cords, and then hoist it in the blast hole. Usually uncoupling charge is used, the uncoupling coefficient K=3.1~3.3, 2# rock emulsion explosive is used, the charge diameter d=80mm, and the weight is 3kg. Four pairs of double rows (24kg explosives) in the lower part of the blast hole, and single row (24kg explosives) in the upper part. Use hemp rope to bind the charge rolls to the two detonating cords, leaving a gap of about 100mm between the charge rolls. The charge per hole is 48kg. Suspend the powder coil chain vertically in the center of the blast hole, and fix the detonating cord at the detonating end to ...

AI Technical Summary

Problems solved by technology

Second, two boxes of explosives, weighing 48kg, plus a 30m detonating cord, weigh close to 100kg, which is too heavy for one person to construct

Third, there is a major safety hazard, that is, under the action of a weight of 100 catties, there is a lot of friction between the detonating cord and the edge of the blast hole

Its disadvantage is that if the cross-sectional area of ​​the cylinder is close to the area of ​​the blasthole, its linear charge density is too large, and when the linear charge density is moderate, its kerf is too far away from the hole wall, so the concentrated energy generated flow is weakened

[0008] In addition, there is a drug bag with "V" grooves on both sides of the drug bag. This kind of special-shaped material is difficult to manufacture, and it is even more difficult to process it into a drug bag.

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