Directional drilling discussion
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You can discuss some theoretical knowledge about directional drilling, and you can also talk about the on-site issues related to it.
For oil and gas pipelines, the curvature radius of the curved sections should be no less than 1500D, while the length of the straight sections buried in the ground should be at least 20 meters. The angles at which the pipeline enters/leaves the ground should be determined based on the performance of the equipment; typically, the angle of entry into the ground is between 8 and 11 degrees, while the angle of exit is between 5 and 8 degrees. In the horizontal section, small-angle deviation is possible, but the performance of the drilling rig must also be taken into account. The construction site should take into account the requirements for piping layout. I’m not an expert in trenchless technology, so I can only discuss some basic aspects. I welcome those with more expertise to join the discussion!
Additional note: Step 1. The drilling rig is installed on the side of the entry point; starting from there, a curve is drilled along the designed path from the entry point to the exit point； As a guiding curve for pre-drilling and pulling back the pipeline. Step 2: During the drilling of guide holes, the diameter of these holes is often smaller than that of the retraction pipeline; to ensure that the diameter of the drilled holes is at least 1.5 times that of the retraction pipeline ； It is necessary to use an reamer to enlarge the guide hole from the excavation point toward the point where it enters the ground to the desired diameter. Step 3: After the underground hole has been pre-expanded to meet the requirements for retraction, the drill pipe, reamer, retraction joint, and the pipeline to be installed are connected in sequence. Starting from the point where the hole emerges from the ground, the hole is expanded while the pipeline is retracted back to the point where it enters the ground.
Different machinery has different requirements depending on the angle of excavation and the angle of burial; it is necessary to refer to the instructions for the specific equipment
The original poster didn’t specify the exact problem; since all basic issues cannot possibly be discussed here, you should read the relevant materials on your own and come back with questions if any. Reference material: The chapter on trenchless tunneling construction by Huang Chunfang, published by Sinopec Press