Using different exchangeable fittings, various drilling methods can be applied in RTG machines, such as:
- FoW(Fron of Wall) method or drilling with double drilling head. When using this method, a casing and auger rotate in opposite directions thus allowing performing holes very close to the buildings.
- A Continuous Flight Auger (CFA) drilling method.When performing piles under this method, an auger drills in to ground and when extracting the auger concrete pumping in free place through tube in auger.
- Kelly drilling method,used to perform big-diameter and high-depth drillings. The so-called Kelly bars and Kelly winch with working tools – auger or bucket – are used to employ this method.
- A Full Displacement Process (FDP) method, i.e. performing drilling while at the same time compacting the ground, is used in for average diameter piles production, when special equipment is screwed in the ground and thus the ground is compacted without displacing it to the surface. Upon reaching a desired depth, concrete is pumped to the hollow to fill the cavity.