High pressure resistant drilled hole sealing method

Abstract

The invention relates to a high pressure resistant drilled hole sealing method. The method comprises the following steps of: inserting a first grouting pipe into a constructed drilled hole; pouring a high pressure resistant sealing material I with a grouting thickness L3 into a position which is 27 to 29m away from the top of the drilled hole by using the first grouting pipe, and after pouring, closing a ball valve; inserting a second grouting pipe with the depth of 1 to 2m, a third grouting pipe with the depth of 5 to 6m, and a return pipe which is positioned at the top of the drilled hole and has the depth of 2 to 3m into the dilled hole respectively; pouring a high pressure resistant sealing material II with a grouting thickness of L1 into the hole mouth of the drilled hole by using the second grouting pipe and sealing the hole, and after pouring, closing the ball valve; and after the high pressure resistant sealing materials at the front and rear sections in the drilled hole are solidificated, pouring compound polyurethane into an interlayer formed by blocking of the two sections of high-intensity sealing materials by using the third grouting pipe until the interlayer with the thickness L2 is filled, and closing a third ball valve and a fourth ball valve. The method is simple, and easy to operate, and has a good effect.

Description

technical field [0001] The invention relates to a high-pressure-resistant drilling sealing method, which is especially suitable for high-pressure sealing of drilling and blasting holes in coal mines, drilling high-pressure hydraulic fracturing sealing, blasting drilling, pressure measuring drilling, gas drainage drilling, coal seam drilling, etc. Water injection drilling and sealing of boreholes such as tunneling, underground and underwater pouring systems. technical background [0002] The geological conditions of my country's coal mines are complex, high-gas coal seams account for 50%-70%, and high-gas low-permeability coal seams account for about 70% of them. In order to improve the air permeability of low-permeability coal seams, technologies such as underground coal seam high-pressure hydraulic fracturing and deep hole loosening blasting are often used to relieve pressure and increase permeability of coal bodies. These technologies require drilling in coal seams, inject...

AI Technical Summary

Problems solved by technology

At present, cement mortar, hole sealer, foam polyurethane and other materials are widely used in China to seal boreholes. However, during the implementation process, there are often phenomena that the borehole seal is not tight, or the strength of the sealant material is not strong enough, resulting in high-pressure water leakage or high-energy gas. The energy is released along the axial direction of the borehole, it is difficult to loosen the coal around the borehole to effectively relieve pressure, and the gas permeability of the coal does not change much

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