Tube Well Boring Services
Tube well boring by reverse rotary/ direct rotary is the standard technique used to install large diameter gravel-packed water supply wells in unconsolidated formations. The reverse-rotary techniques is similar to the standard mud-rotary technique in that a rotary-driven drill bit and recalculated drilling fluid are used to advance and stabilize the boreholes. However, in reverse rotary, the drilling fluid is gravity fed down the annular space of the borehole and the drill string and the return fluid containing the drill-cutting load is pumped upward through the drill stem. This reversal in fluid flow allows for the installation of larger boreholes compared with direct rotary, since the constant diameter of the drill string allows for consistent fluid velocity, regardless of the borehole diameter.
The relatively lower velocity of the drilling fluid in the annular space of the drill string and the boreholes reduces the risk of a formation. To maintain satisfactory fluid velocity and consistency, reverse-rotary drill use larger pumps, drill rods, compressors and drilling reservoirs mud pits than direct-rotary drills.
Hitech Drilling Engineer's fleet of reverse-rotary drills is fully stocked with the tooling and support equipment to handle your most demanding projects. With our truck, trailer mounted reverse rotary equipment, we can complete boreholes and under-reams from 36 inch diameter to 1,500 feet deep in locations ranging from open fields to inside existing well