What is the working principle and process of horizontal directional drilling?

1. The working principle and process of horizontal directional drilling:

1 Construction principles of horizontal directional drilling and pilot drilling

Pilot drilling is primarily done with jet-assisted cutting bits. If the drill string is fed and rotated at the same time, the ramp loses its directionality and enables a straightened hole; if the drill string is only rotated, the reaction force acting on the ramp causes the bit to change direction. There is a probe or transmitter in the pilot bit.

2 Advantages and disadvantages of horizontal directional drilling

Advantages: little interference to the surface, fast construction speed, controllable pipeline laying direction, and high construction precision. Disadvantages: The construction site requires a lot, it is difficult to construct in non-cohesive soil and gravel layer, and it is generally suitable for various soil layers without large pebbles.

3 Construction process of horizontal directional drilling

Construction preparation→measurement and setting out→equipment installation→drilling rig anchoring→mud preparation→pilot hole construction→hole reaming construction→pipe pullback.

2. Introduction of basic structure and functions of horizontal directional drilling rig:

Horizontal directional drilling rig is composed of power system, drilling rig system, steering system, drilling tool, mud system and auxiliary tools. This machine is used in many projects at present, and its applicable range is particularly wide. The following Here is a brief introduction to their structure and function:

1. The drilling rig system is composed of the main unit of the drilling rig, the turntable, etc. It is the main body of the drilling and pulling back operations through the equipment. The main unit of the horizontal directional drilling rig is placed on the drilling rig frame to complete the drilling and pulling back operations. The turntable installed at the front end of the main unit of the drilling rig is connected to the drill pipe, and the output speed, the turning direction of the turntable, and the size of the torque can be changed to meet the requirements of different working conditions.

2. The power system is composed of a generator and a hydraulic power source. The power source provides high-pressure hydraulic oil for the drilling rig system as the power of the drilling rig, and the generator provides electricity for electrical equipment and lighting on the construction site.

3. The mud system is composed of mud pump, mud mixing tank and mud pipeline to provide suitable mud for the drilling rig system.

4. Auxiliary tools and drilling tools are the tools needed for reaming and drilling of horizontal directional drilling rigs. The drill has drill bits, drill pipes, cutters and reamers suitable for various geology. Auxiliary implements include swivel unions, snap rings, and pull heads for various pipe diameters.

Due to its structural and functional characteristics, horizontal directional drilling rigs can lay various types of underground utilities without digging the ground surface. It is suitable for special ground conditions such as clay and sand, and is suitable for most non-hard Rocky areas, high water tables, and pebble formations.