Abstract: An electrical submersible pump assembly for use in a well, including a well having a high gas-to-liquid ratio has a motor, a hollow, tubular drive shaft which drives the pump, and a liquid-gas separator assembly upstream of the pump intake. The liquid-gas separator has a hollow tubular portion, which communicates with the open, lower end of the drive shaft, openings through its sidewall, and a closed lower end. The sidewall also includes at least one outwardly extending projection shaped for urging liquid contained in a liquid/gas mixture flowing towards the pump outwardly, away from the sidewall openings. Preferably, the outwardly extending projection comprises a helical blade which, using either the well casing or a separate sheath, defines a helical channel through which the oil-gas mixture flows prior to reaching the pump intake.

Abstract: An electrical submersible pump assembly for use in a well, including a well having a high gas-to-liquid ratio has a motor, a hollow, tubular drive shaft which drives the pump, and a liquid-gas separator assembly upstream of the pump intake. The liquid-gas separator has a hollow tubular portion, which communicates with the open, lower end of the drive shaft, openings through its sidewall, and a closed lower end. The sidewall also includes at least one outwardly extending projection shaped for urging liquid contained in a liquid/gas mixture flowing towards the pump outwardly, away from the sidewall openings. Preferably, the outwardly extending projection comprises a helical blade which, using either the well casing or a separate sheath, defines a helical channel through which the oil-gas mixture flows prior to reaching the pump intake.