METHOD AND DEVICE FOR COMPLEX PRODUCTIVE BED TREATMENT Russian patent published in 2008 - IPC E21B43/25 E21B28/00 E21B43/16 

FIELD: production industry, particularly to produce fluid from well.

SUBSTANCE: method involves installing and fixing device including cylinder with sucking valve inside cased well, wherein the cylinder receives stepped piston with delivery valve so that stepped piston may slide in axial direction; performing periodic piston reciprocation to apply periodic depression action to reservoir and to pump-out liquid by pressure change in piston underside cavity; providing simultaneous wave bed treatment. Liquid pumping-out and depression and wave bed treatment are carried out in single piston reciprocation cycle. Device additionally has case installed on cylinder to create sealed annular chamber in-between and packer carried by case. Additional valve is installed in lower cylinder part to establish periodical communication of piston underside cavity with productive bed under the action of piston movement. Side cylinder wall has openings, which periodically communicate sealed annular chamber with hole annuity.

EFFECT: increased reservoir recovery by complex productive bed treatment.

3 cl, 2 dwg