Development of rescue truck-mounted drilling rig in ground emergency

Ground drilling is an effective means to rescue the person trapped underground in case of accident in a mine. The rescue truck-mounted drilling rig is an ideal model for mine accident rescue due to its adaptability to a variety of drilling technologies and the advantages of wide formation adaptability, high mobility and strong accident handling capacity. In view of the shortcomings of domestic truck-mounted drilling rig in the construction of life support hole and large-diameter relief well, ZMK5550TZJF50/120 truck-mounted drilling rig was developed. Specifically, the large capacity power head adaptable to various technologies was developed, adopting the design of installation interfaces for large hole spindle, large diameter punching pipe, and gas lift reverse circulation pipe. In such case, the speed torque could be adjusted in a wide range, a variety of drilling technologies could be adapted, the measured maximum torque is 51 350 N·m, and hence the construction of large diameter drilling and accident handling capacity could be realized. Meanwhile, a telescopic mast feeding device of oil cylinder and steel wire rope was designed, which could achieve a long working stroke of 14 m, a short transport size of 13.6 m and a measured maximum pulling force of 1 205 kN, and has the capability of strong unsticking in the hole accident. Besides, the power and electro-hydraulic control system was integrated into the power pump station to provide power and control sources for the truck-mounted drilling rig, drill pipe conveying system and wellhead platform. In addition, the split layout resolved the contradiction between the improvement of drilling capacity and the weight and size of the whole machine, satisfied the requirements of road transportation, and gave full play to the high mobility of the drilling rig. In order to improve the efficiency of tripping and the degree of mechanization, reduce the number of workers and mitigate the labor intensity, the automatic loading/unloading system of drilling rig was developed, realizing the tripping efficiency less than 3 min/rig with the joint operation of HG2-01 rod changing device, hydraulic lifting device and automatic unscrewing device. The drilling rig completed the construction of a relief well with a diameter of 830 mm and a depth of 624.1 m in Ningxia Meihuajing Mine, with an average mechanical drilling speed of 3.1 m/h and a depth of 654.1 m. It is verified with a drilling and rescue capability within a depth of 600 m, which provides equipment support for the accident rescue of mine in China.