Horizontal directional drilling machine rock guiding drilling tool

Compared with the relatively single soil layer guiding drill, the horizontal directional drill can have a variety of choices in the guiding construction of rock stratum. Now the commonly used rock stratum guiding drill has the following three kinds.

Cone bit + mud motor

This is the current directional drilling in the rock construction when the use of multiple guided drilling tools. The rotary bit is supplied with reverse power by the screw drill, and the drilling pressure is applied by the power head of the drill through the drill pipe to break the rock formation. This process does not have high requirements for the main machine, but it has certain requirements for the pressure and flow of the mud system. Small directional drilling rigs generally need to be equipped with high-power mud pumps to use this drilling tool effectively.

Cone bit + double drill pipe

When the horizontal directional drilling rig cone bit cooperates with double drill pipes (the drill pipes are of double-layer structure, and the inner and outer drill pipes can rotate independently), the torque and pressure required by the cone bit to break the rock are supplied by the drill power head through the drill pipe, and there is no need to use the mud motor and large displacement mud pump. Although the drilling tool system has the advantages of less supporting equipment and less mud consumption, the drilling rig structure and construction operation are relatively complex.

DTH hammer + air compressor

DTH hammers are generally driven by high-pressure air to impact, and rotate under the drive of drill pipes to break hard rock layers by reversing the impact method. The broken drill cuttings are blown out of the hole through air (the residual gas of driving DTH hammer operation). Horizontal directional drilling machines have very high construction power in hard rock construction. However, this process is generally only applicable to hard rock formations without groundwater, and air compressors are required to supply high-pressure air, so the construction cost is high.