An underground self-advancing high-pressure abrasive gas jet drilling repair device and method

Abstract

The invention relates to an underground self-propelled type high-pressure grinding air jet drilling repairing device and a method. The device comprises a high pressure air part, a drill bit and a hose, wherein the drill bit comprises a shell, an air inlet, a jetting nozzle, a mixing chamber, a rotator and a prepositioned nozzle; a rotating chamber is arranged in the rotator; the high pressure air part is communicated with the air inlet through the hose; a post-positioned nozzle is arranged at the head end of the shell; a suction channel is penetrated through a side wall of the shell; an impeller is arranged in the rotating chamber. The method comprises the following steps: 1) preparing high pressure air; 2) inputting the high pressure air to the air inlet of the drill bit; 3) spraying the high pressure air from the jetting nozzle; 4) causing the high pressure air and the coal dust act on the impeller; 5) utilizing the high pressure air to drive the coal dust to discharge from the impeller and then spraying the coal dust from the prepositioned nozzle; 6) completing the operation. According to the device and the method provided by the invention, the repairing for collapsed hole and blocked hole can be realized; higher coal breaking impact force can be acquired; the repairing for the drilling hole is benefited; the use efficiency of the drilling hole is increased.

Description

technical field [0001] The invention belongs to the technical field of borehole repairing used for coal mine gas extraction, and in particular relates to an underground self-feeding type high-pressure abrasive gas jet borehole repairing device and method. Background technique [0002] In recent years, with the increase of the mining depth of the mine, the gas extraction conditions tend to be more complicated. For example, when the gas extraction is performed in the high ground stress, surrounding rock fissure development zone and soft coal seam, due to the disturbance of ground stress and external force, the drilling often occurs in the hole. The phenomenon of hole collapse and plugging occurred, which led to the blockage of the gas drainage channel, which greatly reduced the gas drainage flow and concentration. To solve this problem, the commonly used method is to use a drilling rig to re-drill according to the original drilling parameters. This method is not only time-con...

AI Technical Summary

Problems solved by technology

Moreover, the post-intrusion of water will advance the termination time of gas desorption

For the down hole, the water at the bottom of the hole is likely to cause muddying of the coal body and block the gas drainage channel

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