METHOD FOR SELECTIVE ISOLATION OF WATER INFLOWS IN OIL WELLS Russian patent published in 1999 - IPC

FIELD: oil production industry. SUBSTANCE: method can be used at late stage of developing deposit. At high flooding of recovered product that is when it reaches 95%, wells are stopped. Undertaken is temporary isolation of water inflows by injection of viscous-resilient compound. Then wells are started for operation. Output and flooding are assessed. Separated are wells in which flooding is reduced by more than 3%. In case of increased flooding, they are subjected to selective isolation proper. For this purpose, initially injected is viscous-resilient compound, then cement slurry is injected. After drilling through hardened cement stone, undertaken is final shooting of perforation holes in oil part of bed. Bottom-hole of sump is remained by 5 m lower than final perforation holes. Well is completed and brought in operation. Application of aforesaid method improves reliability of isolation of water inflows and reduces flooding of products. EFFECT: higher efficiency. 5 cl