Entry inspection of Tapered Bit:

      (1) Check whether the screw drill bypass valve piston is flexible;

      (2) Turn on the pump. Start with a small displacement, and then gradually increase to the normal displacement. Check whether the bypass valve is closed, the brand of the screw drill disassembly rack, and whether the mandrel rotates flexibly.

      (3) Lift up the drilling tool and check the bypass valve closing condition. Only after everything is normal, can the drilling be carried out.

      (4) During the drilling process, it is necessary to operate smoothly and control the lowering speed. The screw drilling tool disassembly frame is generally suitable for investment, generally 10m/min, to prevent the drill bit and the screw drilling tool from being blocked by the stolen material. During the drilling process, the water hole on the top of the pump can be properly opened, and the Drill pipe disassembly frame should be added, but the time should not be too long, or the clean well flushing fluid should be poured into the drill string every 500 meters.