Spiral Flush Design
Flushing channels are crosswise to the drilling direction.
Back flush creates vacuum to the pilot bit face area.
Air channels are above the ring bit cutting edge.
Sprial Flush design results in no pressure to the ground, no air leakages, and no over drilling so no threat to surrounding structures!
Conventional DTH Drilling
Conventional DTH Drilling has two problem areas:
Pressurised air over drills material. Over drilling removes more material than anticipated changing the ground’s original characteristics threatening nearby structures.
Air that is blown forward travels long distances in loose ground or soft clay. This can cause severe damages to nearby buildings & structures.
As a result, the use of conventional DTH drilling is limited already in several city centers, shorelines and other sensitive areas around the world.