METHOD FOR ISOLATION OF HIGHLY PERMEABLE ROCKS Russian patent published in 1994 - IPC

FIELD: well drilling. SUBSTANCE: method includes running pipe string with hydraulic vibrator in its bottom part to zone of occurrence of highly permeable rocks. Injected in pipe string is fluid with dispersed materials introduced in it. Strength of dispersed materials exceeds strength of highly permeable rocks. Particle sizes of dispersed material are less than sizes of vibration channels. During circulation, well pressure is raised above pore pressure of fluid of isolated rocks. This is effected proportional to reduction of content of dispersed materials in fluid appearing at wellhead. Well pressure is limited by rock hydrofrac pressure. Pressure fluctuations are excited by hydraulic vibrator. Frequency and amplitude of pressure variation excited by hydraulic vibrator are maintained at conditions determined by relations given in invention description. EFFECT: higher efficiency of isolation of highly permeable rocks due to increased radius of isolation effect with rocks simultaneous consolidation and bearing capacity.