METHOD OF SHUTOFF OF WATER INFLOW OVER CEMENTING ANNULAR SPACE IN OPERATION OF OIL AND GAS WELLS Russian patent published in 2003 - IPC

FIELD: oil producing industry; applicable in repairs of oil and gas wells. SUBSTANCE: method includes isolation of overflow channels by cutting out of casing string within interval below and above roof of water-bearing bed, creation of cavern in said interval and filling of cavern with plugging mortar at pressure equalling pressure of hydrostatic column of plugging mortar, which after hardening creates impermeable isolation bridging plug. Casing is cutout 2-3 m below and 5-7 m above roof of water-bearing bed, and cavern is formed by reaming of wellbore in said interval. Claimed method may be realized in operation of wells from underlaying pressure horizons, within interval of fissured and liable to hydraulic fracturing connectors between oil producing and water-bearing beds. EFFECT: higher efficiency of method due to creation of solid ring from plugging material in annular space between oil producing and water-bearing beds. 4 cl