Experimental apparatus for softening hard coal seam through water injection, and application method thereof

Abstract

The invention relates to an experimental apparatus for softening a hard coal seam through water injection, and an application method thereof. The experimental apparatus is provided with a double-end plugging and fracturing device; the double-end plugging and fracturing device comprises a packer; and the packer comprises an outer packer and an inner packer arranged along the length direction of the packer at an interval, and the outer packer and the inner packer are in flexible connection, so enclosed space is formed by a packing section located between the outer packer and the inner packer after pressurization of the outer packer and the inner packer. A high-pressure water injection pump is employed for water injection so as to facture a coal body in the packing section, so the frequent technical problem of incapability of maintaining a pressure during high-pressure water injection can be overcome and conditions are created for subsequent low-pressure infiltration of the coal seam; and the experimental apparatus is simple in structure, good in water injection effect and capable of realizing water injection and pressure maintenance so as to ensure low-pressure infiltration, and thus, the coal seam is effectively softened, the consumption of cutting picks is reduced, and problems in mechanical exploitation of hard coal seams are fundamentally overcome.

Description

technical field [0001] The invention relates to the technical field of coal mining, in particular to a hard coal seam water injection weakening experimental device and a use method thereof which are suitable for mine underground engineering. Background technique [0002] According to the hardness, the coal seam is divided into five categories: extremely hard coal seam 5.0>f>4.0, hard coal seam 4.0>f>3.0, medium hard coal seam 3.0>f>1.5, soft coal seam 1.5>f>0.8, and extremely soft coal seam 0.8>f>0.5 , and the coal cutter is generally suitable for the working face with the hardness f≤4 of the coal seam. [0003] In the production of hard coal seams, due to the hard coal body of mechanized coal mining, it is very difficult for the shearer to cut the coal, and usually the phenomenon of not cutting the coal occurs, which not only increases the consumption of picks, but also often causes For mechanical accidents of coal shearers, in production prac...

AI Technical Summary

Problems solved by technology

[0003] In the production of hard coal seams, due to the hard coal body of mechanized coal mining, it is very difficult for the shearer to cut the coal, and usually the phenomenon of not being able to cut the coal occurs, which not only increases the consumption of picks, but also often causes For mechanical accidents of coal shearers, in production practice, the method of vibrating the coal side and the coal wall is usually used to make the coal seam soft, and then the coal is cut by the coal shearer. There are also methods of water injection through shallow holes in the coal body and deep holes The method of water injection, but the water injection effect is not ideal, and the problem of being unable to maintain the pressure often occurs, which cannot fundamentally solve the problem of using mechanized mining in hard coal seams

Images