METHOD OF WELL COMPLETION Russian patent published in 2003 - IPC

FIELD: oil and gas producing industry, particularly, completion of wells with open bottomholes including those provided with packer. SUBSTANCE: method includes lowering into well of tubing with packer, replacement of clay drilling mud with light-weight drilling mud, setting of packer and product inflow stimulation. Tubing string with packer is lowered down to roof of producing formation. Drilling mud in interval of lowering of tubing string with packer is replaced with light-weight fluid and maintenance of reservoir back pressure. Packer is set. Flexible pipe of coil-tubing unit is lowered into well to bottomhole through tubing string and set packer. Remaining on bottomhole clay drilling mud is replaced with light-weight drilling mud with maintaining reservoir back pressure. Well zone of formation is stimulated by method of varying pressure with aqueous solutions of calcium chloride or with inorganic surfactants during 20 cycles. Well is washed with maintenance of back pressure for, at least, two cycles to wash-out of bottomhole pack. Formation fluid inflow is stimulated. Flexible pipes are withdrawn and well is treated for free flow. Clay drilling mud is replaced with light-weight fluid in interval of lowering of tubing string with packer and on bottomhole. For this purpose, clay drilling mud of high density found in well is replaced stepwise with clay drilling mud with densities lower by 10-20% than that of replaced mud. Displacement fluid is injected in form of process water with carboxymethyl cellulose in amount equaling volume of cavities of tubing pipes, and then, aqueous solution of calcium chloride with obligatory washing of well at each step during, at least, two cycles and with maintaining of reservoir and with maintaining of reservoir back pressure. Value of reservoir back pressure is selected from analytical expressions. EFFECT: higher reliability and efficiency of well completion. 1 dwg