Horizontal directional drilling rig is a kind of drilling equipment used for drilling horizontally or oblique holes underground, to lay a variety of underground utilities, such as pipelines, cables, etc. without excavating the surface. This technology is usually used to lay pipelines, cables, or other facilities underground without affecting the surface topography or causing damage to underground facilities. The working principle of horizontal directional drilling is to set up a drilling rig on the surface and gradually expand and extend the borehole to the target location by rotating the drill bit and advancing the pipe. This method can cross between underground obstacles or geological layers to achieve higher accuracy and less ground interference. Horizontal directional drilling is widely used in urban construction, water resource exploration, environmental protection and infrastructure construction, and is favored by many industries. It is fast, efficient, flexible, and cost-saving, so it is widely adopted. It is widely used in the laying of flexible pipelines such as water supply, electricity, telecommunications, natural gas, coal gas, and oil, and is particularly suitable for sandy soil, clay, and other ground conditions.
1. Drilling with drill bit and drill rod: After fixing the horizontal directional drilling rig, the drill bit drives the drill rod to rotate and move forward according to the set angle under the action of the power head, and drilling according to the depth and length required by the construction under the control of the guide instrument, and passes through the ground obstacles and then out of the ground. During the drilling process, in order to prevent the drill rod from being clamped and locked by the soil layer, the mud pump needs to pump out the expanded cement or mud through the drill rod and drill bit, and it also plays a role in solidifying the channel and preventing the pipeline from collapsing.
2. Back-expansion head back-expansion: After the drill bit and the drill rod pass through the ground, remove the drill bit, install and fix the back-expansion head on the drill rod, drag the power head back, and the drill rod drags the back-expansion head in the reverse direction to expand the diameter of the pipeline.
3. Pipeline back-dragging: While the back-expansion head is back-dragging, the pipeline is fixed behind the back-expansion head, the power head drags the drill rod, and the back-expansion head and the pipeline are dragged back in the reverse direction at the same time until the pipeline is dragged out of the ground to complete the pipeline laying construction.
Non-excavation construction: Horizontal directional drilling technology avoids the damage to the surface environment caused by traditional excavation construction, and reduces the interference and adverse effects of construction on traffic, environment, and surrounding building foundations.
High precision: The equipment has high precision, and it is easy to adjust the laying direction and burial depth. The pipeline has a long arc laying distance, which can meet the design requirements of the burial depth, and can make the pipeline bypass underground obstacles.
Environmental protection: When using horizontal directional drilling rigs for crossing construction, there is no water or underwater operation, which does not affect the navigation of rivers, does not damage the embankments and riverbed structures on both sides of the river, and does not damage the landform and environment.
Economic and efficient: Compared with other construction methods, horizontal directional drilling technology has a fast speed in and out of the site, the construction site can be flexibly adjusted, the construction area is small, and the construction speed is fast.
Working principle of Horizontal Directional Drilling Rig
Drilling device: Horizontal directional drilling machine usually consists of a drilling rig, a drill bit, and a guide tool. The drilling rig is used to provide sufficient power to rotate the drill bit, while the guide tool is used to guide the drill bit to move in the horizontal direction.
Guidance system: The guidance system of the HDD machine can determine the direction and inclination of the downhole drill bit so that the drill bit can accurately drill into the target layer.
Drilling process: During the horizontal directional drilling process, the drill bit first drills into the ground at a vertical or inclined angle, and then the guide system gradually turns the drill bit and drills into the horizontal direction of the target layer.
Drill bit rotation and advancement: Once the drill bit reaches the horizontal position of the target layer, the drill will continue to rotate the drill bit and complete the drilling work by advancing forward.
Completion of drilling: Once the drill bit reaches the predetermined horizontal length or target position, the drill will stop working and withdraw.
