METHOD OF HYDRODYNAMIC ACTION ON BOTTOM-HOLE FORMATION ZONE Russian patent published in 2013 - IPC E21B43/18 

FIELD: oil and gas industry.

SUBSTANCE: method involves lowering to a well of a housing with a jet pump, isolation of an inter-tube space from internal volume of a tubing string above the roof of a productive formation, periodic change of direction of a working fluid flow in a well for creation of cycles of depression with repression, determination of volumes of the pumped-out fluid at depression and creation of hydraulic pulse on the productive formation at repression. According to the invention, direction of the working fluid flow in the well is changed at controlled movement of a jet pump in the housing and value of maximum depression is controlled. Period of repression action is determined as per the value of volume of the fluid pumped to the formation. Periods of action of depression and repression are implemented at equal values of volumes of influx and the fluid pumped to the formation in one cycle. The above volumes in every subsequent cycle are increased. Cycles are continued till the growth of fluid volume values is stopped. Then, chemicals are pumped to the formation. If necessary, the cycles are repeated. Action on the bottom-hole formation zone is ended at depression.

EFFECT: increasing efficiency and operating reliability of the action method, enlarging technological capabilities and conditions of applicability to different types of wells at increase in intensity of hydrodynamic action.

15 cl, 1 ex