A high-pressure hydraulic radial drilling guide device and method under the condition of drilling

Abstract

The invention relates to the technical field of coal seam gas extraction, in particular to a high-pressure hydraulic radial drilling guide device and method under the while-drilling condition. The high-pressure hydraulic radial drilling guide method comprises the following specific steps that firstly, gas extraction drilled holes are constructed in a coal seam, and a self-propelled spraying head connected with a high-pressure hose is mounted in the guide device; then, the guide device and the self-propelled spraying head are overall placed into a drill rod, a high-pressure water pump is started, and the self-propelled spraying head pushes the guide device to enter a limiting drill bit capable of being opened and closed and arranged at the bottom of the drill rod; then, the water outlet pressure of the high-pressure water pump is increased, so that the self-propelled spraying head pushes the guide device to break through a center drill bit body of the limiting drill bit capable of beingopened and closed and a blocking piece mounted in the guide device, and the self-propelled spraying head is guided out from a guide pipe and conducts radial drilling operation on the coal seam; and finally, the guide device conducts repeated drilling operation through drilling rig control and adjustment. The high-pressure hydraulic radial drilling guide device is simple in structure, wide in application surface, and capable of significantly improving the extraction effect of the coal seam.

Description

technical field [0001] The invention relates to the technical field of coal seam gas drainage, in particular to a high-pressure hydraulic radial drilling guide device and method under drilling-while-drilling conditions. Background technique [0002] Underground gas drainage in coal mines is one of the most basic, direct and commonly used methods to prevent and control coal mine gas disasters. However, the gas permeability of coal seams in my country is poor, and the permeability is generally less than 1×10 -3 μm 2 , generally belong to low-permeability coal reservoirs, and gas extraction is difficult. Especially with the increase of coal mining depth in my country, high gas and coal and gas outburst mines are gradually increasing, and deep coal seams are in the geological environment of "three highs" (ie high ground temperature, high ground stress, and high reservoir pressure), and the permeability is getting lower and lower. , seriously affecting the gas extraction effect....

AI Technical Summary

Problems solved by technology

To sum up, the current radial drilling methods all need to implement the drill back process, which greatly increases the radial drilling operation time and also increases the worker's work intensity

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