Long spiral applies to high-speed rail construction, civil construction, rotary excavation in relatively large diameter foundation construction, such as bridge foundation construction is more common.
The basic construction and working principle of rotary drilling rigThe mechanical device of rotary drilling rig mainly includes luffing mechanism, mast, main and auxiliary winch, power head, follow-up frame, pressurizing device, drill pipe, drilling tool, etc.. The parallelogram luffing mechanism, self lifting folding mast; automatic detection control of engine power, rotary positioning and safety protection: automatic detection and adjustment of verticality of drill pipe: the new technology of drilling depth preset and monitoring. Color screen display working state parameters, the control adopts pilot control, load sensing, maximize the convenience of operation, sensitivity and safety and comfort, the full realization of human, machine, liquid, electrical integration.
The auger drills, such as short auger bit, ordinary drill bit, sand drill bit, core and so on, can be drilled into different layers of clay, gravel, pebble and medium weathered mudstone.
Drilling technology and principle of rotary drilling rig. The first is through the rotary drilling rig's own walking function and mast luffing mechanism makes the drill can quickly reach the pile position, the mast guide barrel drill will lower the drill pipes with valve at the bottom of the hole are arranged on the power head device for drill rig, provide torque, pressure device through the pressure head will add pressure to the way drill pipe, drill bits, rotary rock and soil, and directly in the drill rig, and then by the lifting device and the telescopic rod will be made drill hole dumping, such cycles, constantly borrow, dumping, straight to the drilling depth to the design. For the good cohesive rock soil, dry or clear water drilling can be adopted. But in the loose and easy to collapse formation, the static mud wall drilling must be adopted.
The basic difference between drilling technology of rotary drilling rig and reverse circulation drilling technology is that the former is to use the drill to remove the broken rock and soil directly from the hole, while the latter is to eliminate drilling slag by slurry circulation to the hole.