Air-lift reverse circulation drilling technology is often used in geothermal well drilling, but there are many problems along with drilling depth increasing, such as double-wall drill pipe leaking, air-water mixer blo.
[pdf] Reverse circulation is achieved by blowing air down the annulus of the rod, the differential pressure creating air lift of the water and cuttings up the inner tube which is inside each rod. It reaches the deflector.
[pdf] Geotechnical drill rigs are specialized equipment for the rigorous demands of construction and geological projects. These rigs play a key role in geotechnical investigation, providing the capability to assess ground conditions.
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