Hydraulic mining nozzle-air lift device

A hydraulic nozzle for setting a hollow piling in a subsurface soil formation comprising:

• a. a cutting envelope formed by a sheath of generally circular cross section open at its front end and partially closed at its rear end by an annular partition;
• b. an evacuation conduit extending rearwardly of said annular partition and providing fluid communication from the interior of said cutting envelope through said annular partition;
• c. first hydraulic jet means adapted to project hydraulic fluid toward the front opening of said sheath;
• d. first hydraulic fluid conduit means for supplying hydraulic fluid to said first hydraulic jet means;
• e. reverse hydraulic jet means projecting rearwardly from said nozzle and adapted to remove soil from above and maintain clearance behind said nozzle;
• and
• f. secondary hydraulic fluid supply means for providing hydraulic fluid to said reverse hydraulic jet means.