Sanwa Nakabori (Caisson) Auger Series are system to drive ready made hollow spun pile or steel pile inserting auger flight inside of them to discharge soil continuously and outer spun pile or steel pile is driven by force of hollow drop hammer and or by hydraulic cylinders extension counter balanced with downward wire-dragging force.

Air compressor is used to inject compressed air through swivel and hollow stem to make soil discharge easier. And same or different swivel and hollow stem are used to inject cement slurry at the bottom of pile.

This series and methods are used, for example, when bearing layer exists very deep under soft ground.