Coal mine underground acoustic wave transmission device and method

Abstract

The invention relates to a sound wave transmission device and method, which belong to the field of mining drilling instruments, and in particular to a coal mine underground sound wave transmission device and method. The invention converts the measurement data while drilling into fixed-frequency mechanical percussion through encoding, and the acoustic signal generated by the percussion will propagate along the drill pipe to the hole, and the sensor installed at the end of the drill pipe at the hole receives the sound wave signal and Upload to the computer for decoding, and then the measurement data while drilling can be obtained. The invention can be applied to track-while-drilling measurement of conventional drilling, and is simple, practical, convenient and reliable.

Description

technical field [0001] The invention relates to a sound wave transmission device and method, which belong to the field of mining drilling instruments, and in particular to a coal mine underground sound wave transmission device and method. Background technique [0002] At present, the transmission method of hole bottom data in the field of underground coal mine drilling is mainly wired transmission, which has high stability, fast transmission rate and wide application range, but special drill pipes must be used, and the use cost is high; therefore, in recent years, underground coal mines have begun to introduce The mud pulse and electromagnetic wave wireless transmission methods are relatively mature in the field of oil drilling, but due to the differences in working conditions and other aspects, such products are still in the promotion stage. [0003] There are two main technical difficulties in the study of acoustic wave transmission data in oil: transmission distance and s...

AI Technical Summary

Problems solved by technology

In the magnetostrictive principle sound wave generator in the prior art, the diameter of the rod and the coil is more than 80mm, and the frequency is about 500HZ. If you want to reduce the frequency to 30HZ, its diameter is difficult to meet the requirements of the underground working conditions of the coal mine, because the coal mine The common drill pipe in the well is directly about 63-73mm, and the diameter of the instrument in the hole is generally not greater than 50mm

If it is made with a small diameter and meets the size requirements, the signal frequency will be high and the signal strength will be small, which will increase the difficulty of demodulating the orifice signal, and the possibility of realization is small

[0006] Second, it is difficult to meet power consumption requirements

, in the existing acoustic wave transmission communication, since the frequency of the signal sent by the acoustic wave generator using the magnetostrictive principle is relatively high, it is impossible to accurately control the acoustic wave generator to only tap once as the signal 1, so it is transmitted by carrier wave or frequency conversion In this case, the carrier signal must be sent continuously, that is, the sound wave generator is constantly performing actions, and the battery energy consumption is relatively large

Moreover, the driving voltage of the sound wave signal generator based on the principle of magnetostriction requires hundreds of volts. When powered by the battery at the bottom of the hole, it needs to be boosted and other processing. The power consumption is large, and the battery is very large. Drilling, where the number of measurements is intensive

[0007] Finally, the commonly used drill pipes for underground drilling in coal mines must have pressure water flowing through them to cool down the drill bit (there is gas in the drill hole, flushing with water can reduce the temperature of the drill bit during drilling to prevent ignition of gas) and slagging (output from the orifice mud pump) After the pressure water passes through the drill pipe and the drill bit, it will carry the coal slag at the bottom of the hole and discharge along the annular space between the drill pipe and the drill hole). Due to the need to reserve a flow channel, the existing acoustic wave generator is difficult to apply to underground coal mines

[0008] Based on the above problems, it is difficult to apply the existing magnetostrictive acoustic wave generator underground in coal mines. In the prior art, there is no data transmission in underground coal mines by means of acoustic wave transmission.

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