Abstract: A multiphase pump includes a housing having a flow inlet and a flow outlet which are fluidly connected to each other via a flowpath, a rotor arranged in the flow path which propels a fluid from the flow inlet to the flow outlet via the flow path, the rotor has a longitudinal axis which extends for a length of the rotor and a multiphase impeller arrangement, at least one leak path which permits a reverse flow of the fluid from the flow outlet to the flow inlet, and at least one channel which is arranged within the housing, the at least one channel directs a liquid from a liquid source to one of the at least one leak path in the multiphase pump.

Abstract: A method for preventing damage to a multiphase pump includes measuring a differential pressure of a fluid across the pump and an axial position of a rotor of the pump over a time period, calculating a pressure fluctuation by measuring a difference between a maximum and a minimum value of the measured differential pressure over the time period, calculating a dynamic axial position by measuring a difference between a maximum and a minimum value of the measured axial position of the rotor over the time period, comparing the calculated pressure fluctuation with an expected pressure fluctuation value, comparing the calculated dynamic axial position with an expected dynamic axial position value, and selecting an operating condition of the pump based on the comparison of the calculated pressure fluctuation with the expected pressure fluctuation value and of the calculated dynamic axial position with the expected dynamic axial position value.

Abstract: A method for preventing damage to a multiphase pump includes measuring a differential pressure of a fluid across the pump and an axial position of a rotor of the pump over a time period, calculating a pressure fluctuation by measuring a difference between a maximum and a minimum value of the measured differential pressure over the time period, calculating a dynamic axial position by measuring a difference between a maximum and a minimum value of the measured axial position of the rotor over the time period, comparing the calculated pressure fluctuation with an expected pressure fluctuation value, comparing the calculated dynamic axial position with an expected dynamic axial position value, and selecting an operating condition of the pump based on the comparison of the calculated pressure fluctuation with the expected pressure fluctuation value and of the calculated dynamic axial position with the expected dynamic axial position value.

Abstract: The invention provides a centrifugal pressure booster, for pressure boosting liquids, multiphase fluid or gas, the pres sure booster comprising a liquid filled electric motor with a stator and a rotor, with a rotor stator gap between the rotor and stator, a pressure boosting part in the form of a pump or compressor operatively coupled to the rotor, and at least one housing, one fluid inlet and one fluid outlet. The pressure booster is distinctive in that it comprises a rotor stator gap coolant inlet pump, for enhancing the coolant flow through the rotor stator gap. The invention also provides a related method and use of a rotor stator gap coolant inlet pump.

Abstract: Turbomachine for increasing the pressure of a fluid or mixture of fluids, comprising an inlet and an outlet, a casing, a rotatable shaft arranged in the casing, diffusers or similar operatively arranged in the turbomachine, and a means for rotation operatively connected to the shaft. The turbomachine is distinguished in that it comprises: at least one impeller of a mixed flow type arranged on the shaft, the impeller having an inlet and an outlet, the inlet is closer to an axis of rotation than the outlet; and at least one further impeller arranged on a common or operatively connected shaft, chosen from the group consisting of axial impellers arranged upstream of the mixed flow type impeller and radial impellers arranged downstream of the mixed flow type impeller.