Method and device for quickly measuring coal seam gas pressure by upward long-distance drilling

Abstract

The invention relates to a method and a device for fast measuring the coal bed gas pressure through upward remote-distance hole drilling. According to the method, firstly, high-pressure grouting is carried out on each rock stratum under the coal bed to be tested through hole drilling, various cracks are blocked, then, the drilling is carried out into the coal bed, a four-way pipe is inserted, in addition, a capsule hole sealing device provided with a gas pipe, a grouting pipe and a water filling joint is connected to a position near a hole opening of the drilling hole, firstly, a manual pressure test pump is used for filling water into the capsule hole sealing device through a water filling joint so that the capsule hole sealing device is expanded, and the drilling hole is pre-sealed; then, a low-pressure hole sealing pump is connected with the grouting pipe, cement slurry is filled into the drilling hole, after the cement slurry overflows from the gas pipe through the four-way pipe, a pressure meter is connected onto the gas pipe arranged at the hole opening part, and the coal bed gas pressure can be measured. The method and the device can be used for measuring the upward coal bed gas pressure with the distance within 50m, the roadway engineering dug for coal bed gas pressure measurement can be reduced, the measuring equipment is simple, and the operation is simple and convenient.

Description

technical field [0001] The invention relates to a method and a device for quickly measuring the gas pressure of an upward long-distance drilling hole in a coal seam, and is especially suitable for measuring the gas pressure of an upward ultra-distance coal seam under complex geological conditions. Background technique [0002] As we all know, coal and gas outburst is a dynamic phenomenon that occurs in soft coal containing high-pressure gas. Once outburst occurs, it often endangers the lives of coal miners. Identify coal seams within a certain range in advance, and give the conclusion whether coal and gas outburst will occur during the mining process of the coal seam. For determining the type of mine design, take anti-outburst measures in advance, improve coal mine management methods, and avoid outbursts. Hazards play an important role. In the process of identifying coal seam outburst, it is often necessary to measure the gas pressure of the coal seam, which is an important...

AI Technical Summary

Problems solved by technology

Among these hole sealing methods, the mucus hole sealer method has a better effect. Its principle is to place the hole sealer in the drill hole, use two capsules to seal the mucus in the middle, and then use the mucus to seal the gas in the pressure measuring chamber. , to ensure that the gas in the pressure measuring chamber does not leak, the disadvantage is that the distance of sealing is about 10-20 meters

The advantage of cement mortar sealing is that it can seal distant boreholes, but the disadvantage is that the cement mortar solidifies slowly, the gas in the pressure measuring chamber is easy to lose during solidification, and the pressure stabilization time is long

Especially when encountering complex geological conditions, such as the development of cracks in the rock formation, the underground water pressure in the rock formation is easy to communicate with the coal hole, and the coal seam is far above the pressure measurement point, it is difficult to measure the accurate gas pressure value of the coal seam by using the above methods , and a large section of roadway dedicated to pressure measurement must be excavated in advance

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