IMMERSIBLE SUCKER ROD PUMP Russian patent published in 1999 - IPC

FIELD: oil production industry. SUBSTANCE: this pump can be used in recovery of well fluid especially when it is necessary to restore bed output in badly contaminated wells or when non-drillable wells have to be brought in production. Pump has double-stage cylinder and double-stage hollow plunger. Made between wall of cylinder stage of larger diameter in its lower part and wall of plunger stage of smaller diameter is chamber which communicates with external space through system of radial passages in cylinder stage of larger diameter. Space of cylinder stage of smaller diameter in its upper part is opened to external space. Application of aforesaid embodiment of immersible sucker rod pump allows for oil recovery from bed simultaneously with effective cleaning of bottom-hole zone of bed together with restoring well output and acceleration of cleaning process. EFFECT: higher efficiency. 2 dwg