Casing for borehole gas drainage

Abstract

The invention discloses a casing for drilling gas extraction, and relates to the field of coal mine underground drilling. The casing includes inserting pipes, each inserting pipe includes a pipe bodyand an inserting joint, and the pipe bodies are provided with a plurality of flow holes; the pipe bodies and the inserting joints are of an integral structure, one ends of the inserting joints are connected with one ends of the pipe bodies, a plurality of gaps are formed in the pipe walls of the inserting joints, the multiple inserting joints are connected end to end, and the inserting joint of the latter inserting pipe is inserted into the end of the pipe body of the former inserting pipe; and the front half part of each inserting joint is inserted into the corresponding pipe body, the secondhalf part of the inserting joint is exposed, and the gap of the inserting joint extends to the second half part and is exposed with the second half part. The casing for drilling gas extraction has the advantages that the phenomenon of casing blockage during gas extraction is avoided, and a gas extraction passage is maintained to be smooth.

Description

technical field [0001] The invention relates to the field of underground drilling in coal mines, in particular to a casing used for drilling gas drainage. Background technique [0002] After the drilling of the roof of the coal mine working face is completed, the casing needs to be installed to protect the hole, and the gas drainage is carried out through the casing. In the prior art, the casing used for drilling gas drainage uses core pipes throughout the whole process. The casing is lowered by a drilling rig and protected with a palm rope or pipe clip. When using this casing, when the working face pushes through the drill After the hole is drilled, the broken rock in the hole will enter the casing, forming a blockage phenomenon, resulting in a large amount of pressure relief gas without drainage channels, and the single-hole drainage rate decreases rapidly, making it impossible to realize the continuity and maximum of gas drainage, reducing the Work efficiency and safety ...

AI Technical Summary

Problems solved by technology

In the prior art, the casing used for drilling gas drainage uses core pipes throughout the whole process, and the casing is lowered by a drilling rig, and protected with a palm rope or a pipe clip. When using this casing, when the working face pushes through the drill After the hole, the broken rock in the hole will enter the casing, forming a blockage phenomenon, resulting in a large amount of pressure relief gas without drainage channels, and the single hole drainage rate decreases rapidly, which cannot realize the continuity and maximum of gas drainage, reducing the Work efficiency and safety, increase the sealing time, seriously affect the drilling progress

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