In recent decades, with the rapid construction of crude oil pipelines and urban pipelines, horizontal directional drilling has developed rapidly in China and has become an important way of pipeline laying.
Reaming method: after the pilot hole is drilled to the receiving pit, remove the drill bit, replace the reaming drill bit, and start the drill to pull back for reaming.
5.
Since then, a new horizontal directional drilling technology has been formed.
China first introduced horizontal directional drilling technology in the 1980s.
If conditions do not permit, offset the drilling axis as a whole, or replace the rock bit.
When horizontal directional drilling has not been invented, to lay pipelines through rivers or obstacles, it needs to be completed by digging pits and sinking pipes, which is not only inefficient but also costly.
First, seal the pipe head with a seal sleeve, then install a reamer between the pipe head and the drill pipe, and start the pipe drawing construction until the pipe drawing is completed…
4.
When drilling the pilot hole, a bit slightly larger than the outer diameter of the drill pipe shall be installed at the head of the drill tool.
The drilling of guide hole is similar to that of overhead line.
Site layout: at the crossing part of horizontal directional drilling, a working pit is set at the starting point of the pipeline, a receiving pit is set at the key point of the pipeline, and the mud production system and pipeline sending system are arranged at the sending end of the pipeline.
2.
The directional drilling technology in the oil industry later invented the re reaming technology, which also made it possible to lay large-diameter pipelines.
In order to monitor the underground drilling in real time, there is usually a steering tool at the end of the drill pipe of horizontal directional drilling, In the process of opening the drill forward, the steering tool will transmit the drilling data to the ground in real time, and the personnel on the ground will adjust the angle and direction of the drill pipe according to the.
Judge whether there are changes in hard objects or layers according to the resistance to determine the feed water pressure and feed water volume of the water injection machine.
When it is impossible to drill in case of hard obstacles, record the length of drill pipe and determine the position of obstacles.
Because the pipeline jacking path is often changed in oil exploitation, in the 1960s, an American engineer combined the drilling technology used in oil exploitation with pipeline laying technology and invented horizontal directional drilling technology.
Keep the thrust uniform and uniform during drilling.
Common reamer rock reamer starts to pull back the rock reamer for reaming.
If ground conditions permit, exploratory holes can be excavated manually.
Common drill bit common drill bit out of hole rock drill bit rock drill bit out of hole how to turn underground: the drill pipe of horizontal directional drilling is actually slightly bent.
Reasons for reaming: when the diameter of the crossing pipeline is greater than 250mm or the geological soil layer is medium sand, coarse sand and gravel soil, multi-stage reaming should be carried out; The reaming procedure shall be reasonably selected according to the formation conditions and drilling rig capacity.
Flexible pipes with strong longitudinal tensile properties along the pipeline should be used for horizontal directional drilling of pullback pipe.
This process is mainly to pull out the soil in the hole of reaming debris to form a smooth and round pipe installation channel.
3.
After hole cleaning and reaming, replace the mud pan at one end of the drill pipe for mud pulling and hole forming.
The complete construction animation of Part 2 construction process is as follows: the step-by-step process of horizontal directional drilling construction animation is introduced as follows: 1.
The larger the pipe diameter, the more times of reaming and the smaller the drilling rig capacity, the more times of reaming shall also be increased.
At the same time, the water injection machine continuously injects an appropriate amount of water and makes mud by mixing the soil in the hole through the drilling tool, so as to protect the hole wall, maintain the stability of the surrounding rock and play the role of lubrication at the same time.
Drilling rig mobilization: horizontal directional drilling rig is the main equipment, which generally integrates drilling rig system, power system, direction control system and mud system.
Incident pit and receiving pit layout incident working pit 2.
Construction preparation 1.
This design is not only to make it easier for the drill pipe to move underground, but also to control the turning.
Horizontal directional drilling is also to drill the pilot hole first, and then ream the hole with the reamer.
First put the guide rope, and then the traction rope.
