Large diameter bedding drill hole drainage goaf along roof and upper corner gas technology

Abstract

The invention relates to a large diameter bedding drill hole drainage goaf along a roof and upper corner gas technology. The large diameter bedding drill hole drainage goaf along the roof and upper corner gas technology is characterized by comprising that steps that a high level coal seam drilling field is constructed in a return airway; (1), a crawler-type electric drilling machine is used for constructing a long-distance large-diameter drill hole in a drilling field in the mining direction separately forwards and backwards, after a drill tool is exited, a processed borehole protection sleevewith sieve holes of a certain length is pushed into the large-diameter drill hole to seal the large-diameter drill hole; (2), in the main roadway or up a hill, the borehole protection sleeve with thesieve holes and the corresponding extraction pipeline are connected to extract gas in a goaf and upper corner. The amount of drilling construction is nearly 50% less than that of fan-shaped arrangement in a high level drilling field, the cost is low, the large-diameter drill hole is constructed in a coal seam, the construction speed is faster than rock stratum holes, part of the coal is extractedduring the construction to save the cost of coal mining, gas extraction flow rate is large, the borehole protection sleeve is arranged in the large-diameter drill hole, holes are not prone to collapsing, the gas extraction effect is better, and the overlimit function of gas in roadways is effectively eliminated.

Description

technical field [0001] The invention relates to a gas technology for drilling a goaf and an upper corner, in particular to a gas technology for drilling a goaf and an upper corner along the roof with a large diameter along the bed. Background technique [0002] Gas is the main hazard source in coal mine production process. With the improvement of the production capacity of the coal mining face and the acceleration of the advancing speed of the working face, the gas emission will inevitably increase. Due to its long drainage time and simple drainage system, the fan-shaped drilling drilling technology in high-level drilling sites has become the main method to solve the problem of gas exceeding the limit in high-gas, spontaneously combustible and extra-thick coal seams. For high-gas working faces, the fan-shaped arrangement of drilling holes in high-level drilling sites is not only an effective way to solve the gas gushing out of gobs and adjacent layers, but also a feasible m...

AI Technical Summary

Problems solved by technology

However, the disadvantages of fan-shaped drilling drilling technology in high-level drilling sites are as follows: high-level drilling sites generally need to be constructed from the return airway of the coal seam to the roof, the construction slope is steep, and the cost of rock drilling sites is high; fan-shaped layout in high-level drilling sites The borehole diameter is generally 94mm-133mm. The borehole diameter is small, the flow rate is small, the drainage effect is not ideal, and there is a phenomenon of hole collapse, which will seriously affect the drainage effect; the high-level drilling site is generally 50-100 meters long. The number of drilling sites is large and the cost is high; the drainage pipeline is laid in the return airway to connect with the drainage boreholes in the drilling site, and the cost of pipeline laying is high; this method cannot extract the gas in the upper corner

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