A fluid is used to assist the cutting bit operating easily. The bit blending the ground with fluid without excavation does cutting. Using the cutting bit requires a low volume and pressure fluid to have a Safe, Clean, Fast and Reliable drilling. ( Other systems use fluid pressure foe blowing the whole open, which may weaken the stability of the surrounding ground. This also requires high fluid volume and pressure which is not safe nor clean).
Controlled steering with cutting bit ( steering is not using fluid pressure)
Since the cutting bit is the method of actual cutting (not the fluid) . the standard Directional Boring Machine is capable of drilling through rock, as ground conditions may be vary, so the bores can be completed in a reliable, safe manner.
Directional Boring unites available for working in solid rock conditions with steering capabilities, with safety , using a very low volume of fluid (only 30 liters per minute require clean , safe, reliable, proven technology.
The fluid is mixed with natural bentonite (which is pure clay ) safe for environment.
The Directional Boring technology proved its success and has been approved worldwide since several years.