Coal mine downhole hydraulic jet tree-shaped drill hole guide device and method

Abstract

The invention relates to a coal mine downhole self-propelled hydraulic jet tree-shaped drill hole guide device. The device comprises a drill rod, a guider, a drill bit and a dial. The drill rod is in threaded connection with the front end of the guider. The drill bit is in threaded connection with the tail end of the guider. A self-propelled drill bit connected with a high-pressure hose penetrates through the middle of the drill rod and then passes through the guider, the purpose of vertical guide to horizontal guide of the self-propelled drill bit is achieved, and finally self-propelled horizontal drilling is conducted on a coal seam. Horizontal steering of the guider is achieved by guider rotation driven by rotation of the drill rod, and the rotation angle is controlled by the dial. The dial is fixed to a chuck at the front end of the drill rod and the front end of a drilling rig. The device has the main effects that vertical guide to horizontal guide of the self-propelled drill bit along a guider track within a certain curvature radius is achieved, and then horizontal drilling of the self-propelled drill bit in the coal seam is achieved. The device is simple in structure, convenient to operate and mainly suitable for drilling tree-shaped drill holes in the gas extraction process of the low-air-permeability coal seam.

Description

technical field [0001] The invention relates to an underground drilling guide technology in coal mines, in particular to a guide technology used for self-propelled drilling into tree-shaped boreholes in the gas drainage process of low-permeable coal seams. Background technique [0002] Many coal seams in my country have the characteristics of low permeability, etc., and conventional methods are difficult to effectively extract gas from coal seams with low permeability. How to increase the air permeability of coal seams is the key to solving the problem of gas drainage in low permeability coal seams. [0003] As an effective reservoir permeability enhancement technology, hydraulic technology provides a feasible method to solve the problem of low permeability of coal seam, and is an effective way to increase the permeability of coal seam. Hydraulic technology uses high-pressure water as the driving force to expand and extend the original cracks in the reservoir or artificially...

AI Technical Summary

Problems solved by technology

[0005] ①The "Radial Horizontal Well Steering Device" announced by CN203285334U has only one curvature, and it is difficult to turn the high-pressure hose;

[0006] ② None of the above technologies have studied and defined the width of the steering guide track, resulting in that the high-pressure hose drill bit cannot be stuck when the guide hole is too small, and the actual restraint cannot be played if it is too large;

[0007] ③ The annular space of the guide described in the above technologies is small, and the slag discharge is inconvenient, which affects the smooth advancement of the drill bit;

[0008] ④The guiding devices of the above technologies are all independent. There is no tool for drilling or reaming at the front end of the steering device. In the case of small or collapsed female holes, it is difficult to lower the steering device to the female hole. reserved location;

[0009] ⑤ The operation of the guide device to achieve precise steering is complicated or the problem of how to turn is not considered

[0010] Due to the above problems of the guide device, it is not conducive to the development of self-propelled radial drilling, and also limits the application of radial horizontal wells in coal mine gas drainage

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