METHOD FOR FORMING WELLS AND EXCAVATIONS IN SEDIMENTARY ROCK LAYERS AND FROZEN SOIL Russian patent published in 2004 - IPC

FIELD: well cutting and excavation forming technology. SUBSTANCE: method includes weakening and destroying rock in the pit-face by means of jets of operation agent under pressure, removing any drilling from boring area and well hollow to well collar while weakening and destroying rock in the pit-face, forming well walls by means of effecting on drilling stream with a jet of operation agent perpendicular to said stream, acoustic oscillations being imposed on said jet, while portion of rock particles from the pit-face is incorporated into well wall and another portion of said particles moving upwards with the drilling stream is effected on with compressed gas, portion of which is supplied by means of co-axial gas-main, inner line of which is connected to compressed gas supply, another portion of said gas being periodically fed into well hollow for forming upward stream directed towards well collar, by means of which stream blow-through of well hollow is performed without combining blow-through and well cutting operations. EFFECT: increased well cleaning reliability and capability for forming well walls in unstable geological structures. 1 dwg