Rim angle excavation method by blasting for natural side hill

Abstract

A method for blasting natural hillside corner belongs to the field of opencast iron ore mining and is designed aiming at the problem that a drilling machine is unable to punch, so that the formed irregular triangular sloping surfaces can not be treated when the slight pitch natural hillside is mined in an opencast way. Vertical holes are drilled at the juncture of the natural hillside and production steps, the pitch-row is reduced by 2-3 m compared with the normal operation, and the hole depth is deepen by 2-5 m compared with the normal operation. The bottom of the deep hole is provided with explosive having high density and power, and the blasting energy is utilized to blast the part close to the steps. After cleaning up, a down-the-hole drill is used for drilling 2-3 lines of horizontal holes on the crushing surface after being blasted, wherein the pitch-row is 1-2 m, and the hole depth is 6-11 m; the hillside corner is blasted by adopting the simultaneous blasting technology. The method has the characteristics of thorough blasting treatment, effective ore recovery and the like, and can be applied to the corner blasting of various slight pitch hillside surface mines.

Description

technical field [0001] The invention belongs to the field of open-pit iron ore mining, and mainly relates to a natural hillside corner blasting method applied to gently inclined natural hillsides in open-pit mining operations. Background technique [0002] In the production of open-pit mines, the blasting of open-pit mines uses roller cone drills to drill vertical deep holes on the upper part of the steps, and the drilling steps have high flatness to facilitate the drilling of roller cone drills. Since the natural hillside is an irregular slope surface with unequal slope, the roller cone drilling machine cannot drill holes in this part, so the part of the natural hillside will form an irregular triangular slope surface due to no blasting in the later stage, which is difficult to deal with. In the past, small-diameter rock drills were generally used to drill shallow holes in the upper part of the slope, and the blasting treatment was carried out several times. Due to the narr...

AI Technical Summary

Problems solved by technology

Since the natural hillside is an irregular slope surface with different slopes, the roller cone drilling machine cannot drill holes in this part, so the part of the natural hillside will form an irregular triangular slope surface in the later stage due to no blasting, which is difficult to deal with

In the past, small-diameter rock drills were generally used to drill shallow holes in the upper part of the slope, and the blasting treatment was carried out several times. Due to the narrow local space and narrow working face, the treatment cycle was long and the efficiency was low, which seriously affected the mining operation level.

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