METHOD FOR CLEANING CENTRIFUGAL PUMP OF OIL WELL FROM PRECIPITATION Russian patent published in 2020 - IPC E21B37/06 

FIELD: oil industry.

SUBSTANCE: invention can be used to remove various types of precipitation from the cavity of electric-centrifugal pumps, as well as paraffin deposits from the walls of the upper part of the tubing string. Method includes shutdown of well, supply of current to valve electric motor with withdrawable stem of shutoff member, washing the cavity of the electric submersible pump with liquid from the tubing string under pressure, supplying the reversed polarity current to the electric motor and closing the valve with further start of the pump. Current supply to the valve electric motor for extension of the shutoff rod stock is performed with the pump running before it is stopped for cleaning, then pump is stopped and to column of tubing string from wellhead is pumped design volumes of chemical solvent precipitate and displacement fluid, and then reverse polarity current is fed to the electric motor to return the retractable rod to the extreme lower position and to seat the valve into the seat, after which the estimated dissolution time is maintained.

EFFECT: simplified technology of cleaning the pump of precipitation, higher reliability and efficiency of cleaning.

1 cl, 3 dwg