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The rotary jet drill is installed in the bottom of the drill pipe, the top of the drill is inlaid with alloy, easy to drill pipe drilling, the drill pipe is equipped with two nozzles on both sides of the barrel, the diameter of the nozzle is 1.6~3.0mm earlier, in the nozzle around the annular nozzle, to ensure coaxial jet slurry. Three single nozzles are installed on the tool body to spray high pressure water. For some soft geological structures to the end, no need to replace the drill, can be slowly lift rotary jet, improve work efficiency.