Hello,

this is a rotary drilling rig inspired by the Liebherr LB 44 rotary drilling rig "Mr. Torque". This kind of drilling rig is used for making deep pile foundations. It can drill holes with a diameter of up to 3 meters.

The version I made shows the LB 44 in the process of Kelly drilling. Kelly drilling is one of many ways to make pile foundations. First, the rig drills a metal tube into the ground. Then, it uses an auger drill to clear the tube's inside from dirt. After that, the rig grabs another metal tube which gets connected to the first one (already in the ground) and the rig continues drilling the tubes into the ground. This is followed by clearing the inside from dirt again using the auger drill. This process is repeated so long until the desired depth is reached. A metal cage gets pulled up by the rig's crane and gets lowered into the hole before it is filled with concrete. Finally, the rig connects to the metal tubes again and drills them out, one after the other. When all of them are out the rig's job is done. It has successfully made a new pile foundation.

Pile foundations are needed when the ground itself would not be able to support a building. If this is the case, concrete piles reaching down to solid rock (or other material stable enough) are built. These are the pile foundations the building will be sitting on.
This has the effect that the building's weight is distributed directly to a solid base (the rock) and does not squeeze the softer ground above. If you construct buildings on soft ground the building might tip after a while because it sank into the ground. To prevent buildings from tipping or even falling over pile foundations are needed which are made using rotary drilling rigs like this one.

Enjoy!