DOWNHOLE VALVE DEVICE Russian patent published in 1998 - IPC

FIELD: equipment for oil production, in particular, oil-well sucker-rod pumping units used in oil-gas producing industry, in mechanized oil production and also in the field of manufacture of hydraulic machinery. SUBSTANCE: downhole valve device has hollow body installed eccentric to tubing string and made with two holes for communication of its own hollow with hollow of tubing string and one hole for communication of its own hollow with annular space. Gate is installed for closing the hole communicating the hollow with annular space. Gate is used in the form of two-position plunger with collar seals which fix plunger in its upper position due to material flexibility and ensuring overlapping by plunger of hole communicating body hollow with annular space owing to creation of rarefaction in body hollow under plunger. With pressure differential built-up between annular space and tubing hollow (for instance, killing) plunger moves upward up to stop and fluid runs over to tubing hollow bypassing the sucker-rod pump. To close the valve, fluid is supplied to tubing hollow. EFFECT: higher operating reliability and simplified design. 1 dwg