High pressure earth grouting appts. - has head with core and ring nozzles to discharge liq. and gas jets respectively above grout discharge

摘要

A concentric triple-walled pipe rod is fitted at the upper end with a swivel and supply assembly for receiving separately compressed air, pressure liquid and pressurised cement milk. At its lower end the pipe rod has working head comprising a laterally directing and concentrically arranged double jet nozzle, with a core nozzle element and an outer ring nozzle element. The core nozzle element is adapted for injecting a liquid core jet containing no earth-solidifying agent and at a high velocity at lest equal to a half sonic velocity. The outer ring nozzle element is adapted for injecting a ring gas jet enveloping the liquid core jet and the working head has a cement mild discharge device positioned at a lower level than the double jet nozzle.