Self-adaptive deformation gas extraction drilled hole sealing device

Abstract

The invention relates to a self-adaptive deformation gas extraction drilled hole sealing device, and belongs to the technical field of coal mine downhole gas prevention and governance projects. The device comprises a hole sealing unit and two hole sealing pipes; gas inlet ends of the hole sealing pipes are arranged inside a drilled hole; and the gas inlet ends of the hole sealing pipes penetrate through the hole sealing unit. The device can realize self-adaptive deformation to the drilled hole of the hole sealing pipes, the traditional modes of PVC straight pipe inserting or screw thread connection are not required, and disjointing of inserting between pipes or screw thread connection caused by drilled hole deviation and deformation is avoided; the grouting stress bearing capacity of the hole sealing pipes is further improved, and the situation that the hole sealing pipes are flattened under grouting pressure and grout enters the hole sealing pipes is avoided; and the sealing performance between hole sealing pockets and grouting air chambers is ensured, and grouting stress is improved to ensure that the grout can effectively permeate into seams between coal masses.

Description

technical field [0001] The invention belongs to the technical field of underground gas prevention and control engineering in coal mines, and relates to an adaptively deformable gas drainage drilling and sealing device. Background technique [0002] The effective sealing of gas drainage boreholes and coal fissures around the holes is the basic premise to ensure the negative pressure of gas drainage and increase the concentration of gas drainage. The research on the concentration and quantity increase of gas drainage has always been a hot and difficult point in gas drainage; the research on the concentration and quantity improvement through gas drainage drilling can be used for the prevention and control of coal and gas outburst, the standard of coal seam gas drainage and the reduction of gas during mine production. The amount of gush is of great significance. [0003] At present, the more mature and effective sealing method for gas drainage drilling is the two-blocking-one-i...

AI Technical Summary

Problems solved by technology

However, the traditional two-blocking-one-injection sealing method generally adopts flame-retardant and antistatic PVC straight pipes with a length of 3-6m, and the pipes are connected by plugging or threading; the straight pipes cannot be well adapted to the holes. Offset and deformation, resulting in the disconnection of the plug or screw connection between the pipes, resulting in the flattening of the sealing pipe under the grouting pressure during the grouting, and the grout flowing into the sealing pipe along the disjointed position, causing the sealing pipe to be blocked ; Since the predetermined grouting pressure cannot be reached, the grout cannot effectively penetrate into the coal fissures around the hole for sealing

On the other hand, the traditional two-blocking-one-injection sealing method generally uses a flame-retardant antistatic PVC straight pipe with an outer diameter of 50 mm, which cannot realize the flow control of the borehole under different drainage periods and different drainage attenuation characteristics.

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