High-velocity jet digging method
AssigneesChemical Grout Company, Ltd., Kajima Corporation
InventorsTeruo Yahiro, Hiroshi Yoshida
Life of this patent
Estimating the term…
Abstract
The method of digging by piercing soil and rock with a jet of liquid discharged at high velocity from a nozzle together with high-velocity air jets discharged from another nozzle arranged concentrically around the liquid nozzle, characterized by the velocity of the air jets being at least half the velocity of sound.
Claims4
A method of digging in the earth comprising the steps of moving a nozzle along a subterranean longitudinal path while directing a high velocity jet of liquid from the nozzle in a direction which is transverse to said path, surrounding the jet of liquid with a gaseous jet directed substantially parallel to the jet of liquid, reducing increases in the cross section of the jet of liquid and increasing and making more uniform its effective length by maintaining the velocity of the jet of gas at least about one-half the velocity of sound in the gas.
Dependencies are inferred from the claim text.