PROCESS AND GEAR FOR DEVELOPMENT AND CLEARING OF FACE ZONE OF WELLS BY PULSE DRAINAGE Russian patent published in 2000 - IPC

FIELD: oil industry. SUBSTANCE: invention is related to methods of development and clearing of face zones of production wells in oil fields. Wells are treated for 15-45 cycles. Each cycle includes 6-30 depression- repression drainage pulses created by formation of positive pressure in well that exceeds seam pressure by pumping of fluid into well clearance. Ground interrupter opens well abruptly and fluid flows out over tubing string into ground collection tank. When flow reaches highest rate well is shut off abruptly and damping standing wave is formed which during 2.0-2.5 s reaches sump of well and returns to well-head. Face zone of seam is subjected to pulse bumps. Vibrations are controlled by well-head manometer and are interrupted at start of period of return of wave back to well-head enhancing depression carry-away of contaminants from face zone by cophasal flow of fluid over tubing string into chute vessel. Flow continues for 2.0-4.0 s and then new standing wave is formed. This procedure is repeated till positive pressure in well decreases. Fluid is pumped with constant productivity to control time when specific positive pressure in well is achieved. If time grows then treatment continues, otherwise treatment is stopped. Gear for realization of process includes ground interrupter installed in throw-away line close to collection tank, pressure transducers of well clearance and of space of tubing string. Funnel traditionally installed in production wells is placed in tubing string opposite to perforation interval or above it. Tail part of 3-5 tubes of smaller diameter than tubing string is mounted above funnel while complex wells are treated. Contaminants of well treatment go from face zone into space of tubing string and are lifted into collection tank. EFFECT: enhanced efficiency and expanded application range of process. 2 cl, 3 dwg, 1 tbl