DOWNHOLE VALVE DEVICE FOR FLUSHING OF TUBING TO REMOVE ASPHALT-RESIN-PARAFFIN ACCUMULATIONS Russian patent published in 1997 - IPC

FIELD: oil producing industry, in particular, downhole valve devices applicable, mainly, in tubing flushing to remove asphalt-resin-paraffin accumulations. SUBSTANCE: device has branch pipe with through channel communicating with tubing. Valve body has lower and upper holes and radial channel. There is hollow rod with radial channels, fishing head and shank. Shank accommodates spring-loaded gate. Rod is installed tightly in valve body openings and in valve body hollow. Downhole valve device is installed as component of tubing about 50 m below the accumulation interval. Working agent is injected to well annular space to pass through radial channels of valve body, to its hollow, through rod radial channels, spring-loaded gate and shank, through channel of branch pipe to tubing. EFFECT: reduced volume of used working agent and pressure of flushing and provision of emergency killing of well. 2 dwg