Detection technology and application of gas extraction drilling trajectory

Gas extraction drilling space position measurement is an important means to avoid gas extraction blank areas to ensure coal mine safety production. Reasonable arrangement of drilling is the key to the use of drilling, while the drilling trajectory is a key factor affecting the effect of pumping drilling holes. At present, the mine trajectory detection technology cannot achieve multi-hole three-dimensional trajectory imaging, and the analysis of drilling trajectory deviation is superficial, which cannot reasonably guide the construction of drilling holes. The handheld mining drilling trajectory instrument is developed based on the technical principle of electronic compass and gyroscope, to realize mine drilling group management, 3D trajectory imaging and drilling deviation analysis. The equipment is applied on site in the drilling hole of the 21210 working face of the Chensilou Mine Area, the results show that the equipment can accurately calculate the vertical offset and horizontal offset, final hole inclination, azimuth angle and hole depth of the drilling hole, and the terminal software of the equipment can image the three-dimensional trajectory of the drilling hole to realize the management of the drilling group, and the drilling deviation analysis shows that the probability of the drilling trajectory offset to the left is greater than the probability of the lower right shift. Due to the influence of drilling pressure and geological conditions of the working face, the azimuth angle and inclination angle of each measurement point of the drilling hole deviated from the design value, and 40% of the drilling trajectory is greatly deviation from the design value. The track deviation after drilling is easy to lead to the extraction of blank zone, which affects the gas extraction efficiency, and the subsequent drilling construction of the working face needs to adjust the construction method according to the deviation trajectory of the drilling to ensure the effectiveness of the drilling scale and improve the gas extraction effect.