The FlexBor aims to be a cost-effective, environmentally safe trenchless method and tooling. The FlexBor is designed to virtually eliminate ‘frac-outs’ / ‘inadvertent returns’ that are often associated with horizontal directional drilling and the use of bentonite.
The Patent Abstract reads: “A cutting assembly and method for drilling an underground borehole. The cutting assembly includes front and rear cutting heads of different diameters mounted on a shaft. An air passage defined through the cutting assembly may be placed in fluid communication with a pressurised remote air source and with a bore of a casing extending rearward from the cutting assembly. Pressurised air flows through the air passage and entrains cuttings produced by the front and rear cutting heads. A housing extends rearward from the larger diameter rear cutting head and an auger provided within the housing aids in directing cuttings into the casing. The auger rotates independently of the rest of the cutting assembly and may be configured to further reduce the size of the cuttings. A collar on the housing seals the borehole cut by the rear cutting assembly and aids in preventing frac-out.”
