| Similar technologies at home and abroad | Directional drilling equipment in underground coal mine | Compared |
Directional drilling equipment | The power of the directional drilling rig is not more than 90kW, and the rated torque is less than 6000Nm; The pump pressure of the mud pump is lower than 9MPa, and the flow rate is lower than 320L/min;The torsional strength of the drill pipe measured while drilling is lower than 19000Nm, and the impact energy of the non-magnetic drill pipe is about 50J. | The power of drilling equipment is greater than 240kW, and the maximum torque reaches 23000Nm;The maximum output pressure of the mud pump truck is 13MPa, and the maximum output flow is 800L/min;The torsional strength of the drill pipe measured while drilling reached 34000 Nm, and the impact energy of the non-magnetic drill pipe reached 220J. | Xi'an Research Institute International Leading |
Measurement while drilling technology and instruments | Wired method is adopted to transmit the measurement while drilling data, which relies on the special cable drill pipe;As the length of the borehole increases, the stability of signal transmission decreases;It cannot meet the needs of high-efficiency composite directional drilling for near-horizontal holes. | Based on limited transmission measurement while drilling, a wireless transmission measurement while drilling system has been developed, which can be used with various types of drill pipes.;The transmission depth exceeds 2000m, long-distance signal transmission is stable, and the failure rate is low;It can Meet the needs of highly efficient composite directional drilling for near-horizontal holes. | Xi'an Research Institute International Leading |
Supporting process system | Using sliding directional drilling technology for drilling construction, the drilling efficiency is low, and the smoothness of the trajectory is poor. The diameter of the final hole is 96mm, and it is difficult to form holes in the complex and broken coal rock. | Using the composite directional drilling technology system for drilling construction, the comprehensive drilling efficiency is increased by more than 40%, and the smoothness of the trajectory is increased by more than 60%. The maximum diameter of the final hole is 220mm. It can be used to form holes in complex broken coal and rock formations. | Xi'an Research Institute International Leading |
Overall technology and application effects | It is suitable for directional drilling in medium-hard and stable coal seams within 1000m. The maximum drilling depth in the coal seam is 1212m, the maximum depth of the large-diameter drilling hole in the roof rock layer is 500m, and the maximum drilling depth of the floor rock layer water damage prevention and control drilling hole is 610m. It is mainly used for pre-mining gas pre-drainage and water hazard prevention. | It can meet the requirements of directional drilling above 3000m. The depth of coal seam gas drainage drilling has been increased to 3353m, the depth of large-diameter drilling in the roof rock layer has been increased to 1026m, and the drilling depth of water damage prevention and control drilling in the floor rock layer has been increased to 1227m. It has realized regional pre-mining gas pre-drainage, high-efficiency mining pressure relief gas drainage and advanced water hazard prevention and control. It is also promoted to be used in mine fire prevention, dust control, accident rescue and other fields. | Xi'an Research Institute International Leading |