Drilling process demands an attentive attitude, control and adherence to technological characteristics at every step.
Preparatory works
Before underground communications laying, the landscape and equipment must be prepared:
- Site development for the drilling machine is of universal size, 10х15m.
- If necessary, provide a detour road for the machine.
- Set down the drilling equipment in appropriate place of the pilot boring launch.
- Fix all necessary systems before the operation.
- Adjust all necessary drilling tools.
- Adjust the radio communication between team members.
- If it’s necessary, built an additional lead for bentonite liquid and groundwater.
At the preparation stage, in order to bring any harm to the existing pipelines it is important to calculate the location of them. It is also necessary to have the 10 m distance between the main machine and mud mixing system.
It is also very important to explore the soil of project and choose the appropriate drill bits and reamers before pilot drilling. The whole drilling object must be protected with a yellow warning tape.
Drilling process
After finishing the preparatory work, the next stage is drilling process:
Pilot boring requirements:
- The diameter of pilot boring is 10 cm.
- Adjusting drill bit by 10 – 20 ° relative to the horizon line;
- Pilot boring path is checking every 3 meters’ length.
Backreaming process requirements:
- Expansion of the pilot hole: the drill bit is removed and replaced by an appropriate reamer;
- Full extension of the reamer through the formed channel with constant correction of movement.
It is necessary to use a drilling mud during whole drilling process. The drilling mud must have sufficient gel strength to keep cuttings suspended for transport, to form a filter cake on the borehole wall that contains the water within the drilling fluid, and to provide lubrication between the pipe and the borehole on pullback.
It is important to consider the possibility of soil caving. In order to exclude the violation of the technology, it is necessary to connect all parts of the pipes with each other reliably.