Electronically controlled single-loop water-plugging overburden strata fracture detection method

Abstract

The invention discloses an electronically controlled single-loop water-plugging overburden strata fracture detection method. The method comprises the following steps that: an electronically controlled single-loop water-plugging overburden strata fracture detector is prepared firstly, wherein the detector is provided with an upper hole sealing capsule and a lower hole sealing capsule respectively at the two ends of a connecting tube; an electronically controlled water flow control device is arranged in the lower hole sealing capsule; and when the detector is used, the operation of detection can be performed just by directly connecting a water inlet pipe of the detector to a drill pipe of a drilling machine, pressing the water inlet pipe of the detector into a drilled hole by using the drill pipe, and connecting an injected water observation device to a water inlet pipe of the drill pipe. According to the invention, hole plugging and water injection are implemented by using the same loop and without using an external high-pressure air duct, so that the situation that an effect of effective hole plugging can not be achieved due to the occurrence of fractures caused by that the high-pressure air duct is rubbed and extruded with the wall of a drilled hole is avoided, a detection system is simplified, operation steps are simplified, and the reliability of water plugging is greatly improved.

Description

technical field [0001] The invention relates to a technique for observing the development of cracks in the overlying rock under a mine shaft. Background technique [0002] Coal seam mining has a destructive effect on the surrounding rock mass, and the overlying rock stratum has caving zones, water-conducting fissure zones and curved subsidence zones from bottom to top, among which the caving zones and water-conducting fissure zones are good channels for roof water. When there is a water-rich layer above the coal seam, whether the water-conducting fracture zone penetrates the aquifer directly determines the safety of the working face. Therefore, it is of great significance to correctly determine the development of the water-conducting fracture zone. [0003] The technology related to this application is a Chinese patent (Application No. 90106348.7), which discloses a double-ended water stopper and the use of a double-ended water stopper to inject water into the borehole and d...

AI Technical Summary

Problems solved by technology

The disadvantages of this method are: 1. Use the rubber hose to inject water. When the probe rod goes deep into and pulls out the drill hole, the rubber hose rubs against the borehole wall, and the rubber hose is often worn out and broken, which makes it impossible to continue the test; 2. Use the rubber ring alone The pressure of the sealing capsule is controlled by the valve, and the rubber is prone to fatigue, resulting in a decrease in the pressure of the plugging hole, which cannot effectively plug the hole, and the reliability of the plugging hole is reduced; 3. When injecting water into the drill hole, due to the resistance of the valve rubber ring, the water injection is often slow and takes a long time. Time cannot fill the plugging section of the borehole with water, resulting in inaccurate measurement; especially when the cracks in the plugging section of the borehole are large, it is impossible to fill the plugging section of the borehole with water at all, and it is impossible to obtain the per unit time of drilling. The amount of water leakage, so that the development of borehole fractures cannot be accurately obtained

[0005] However, since the high-pressure air pipe and the drill pipe enter the borehole together, under the harsh conditions underground, the high-pressure air pipe can easily generate friction and extrusion with the wall of the borehole and the drill pipe, destroying the sealing performance of the high-pressure air pipe. It even breaks the high-pressure air pipe; the high-pressure air pipe is used to seal the drill hole, and the sealing pressure is manually adjusted. The sealing pressure will be adjusted to a higher level, thereby reducing the life of the sealing capsule, and even causing the capsule to burst, seriously affecting the normal observation of the water-conducting fracture zone and the accuracy of the observation results

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