DEVICE FOR STIMULATION OF WELL BOTTOM-HOLE ZONE BY DIFFERENTIAL PRESSURE PULSE Russian patent published in 2000 - IPC

FIELD: oil producing industry; devices for increase of production rate of wells operating by means of deep-well sucker-rod pumping plants. SUBSTANCE: device has cylindrical body with side holes and plug in lower end part. Located in body for reciprocation is plunger with valve. Installed on tubing string is branch pipe carrying sealing member. Device body is telescopically installed on tubing string branch pipe for axial motion and engagement with sealing member through movable stop. Sealing member is in form of hollow cylindrical flexible collar with holes made in its middle part. EFFECT: higher efficiency of bottom-hole formation zone due to effect of multiple pulses of differential pressure and creation of cyclic sign- varying pressure gradients in zone of drainage with simultaneous pumping out of fluid from well. 2 dwg