DEVICE FOR PULSE-DRAWDOWN STIMULATION OF BOTTOM-HOLE FORMATION ZONE Russian patent published in 2001 - IPC

FIELD: oil-producing industry, particularly, devices for stimulation of bottom-hole formation zone by drawdown pulse to increase production rate of wells operated by sucker-rod pumping units. SUBSTANCE: device has a body with side opening and with plug in lower end part accommodating reciprocating plunger with valve. The body upper part has a bushing located in branch pipe for axial motion. Installed on branch pipe is sealing member. Cylindrical body is concentrically arranged in perforated case rigidly connected to branch pipe. Perforated case thrusts artificial well bottom-hole with its lower plugged end. Bushing is connected with movable stop of sealing member with the help of pins passing through longitudinal windows made on branch pipe. EFFECT: higher reliability of sealing member of device and provided lowering into inclined wells without complications, prevented contamination of bottom-hole in the course of stimulation due to accumulation of mechanical impurities in perforated case with their subsequent removal during device lifting to surface. 1 dwg