Barbco Inc. recently unveiled the Flexbor method to the trenchless community. Flexbor is designed to virtually eliminate inadvertent returns (frac-outs) that are often associated with horizontal directional drilling (HDD).
It reduces costs in most cases, by requiring one tool to create the needed hole diameter. It reduces the length of the crossing as it can be pitted in place. This gets the machines centerline on, or close to the elevation of the proposed bore.
Similar to a traditional auger boring method, the spoil and downhole pressures are contained in the drive casing. The spoils are carried to the surface with compressed air. Small amounts of water can be added to assist in the removal of the spoils.
Larger tools use an auger within the system which mechanically mixes and breaks down the soil. With traditional trenchless installation, there are often problems and concerns related to the environmental disruptions caused during drilling.