The invention relates to a method for operating a compressor (100), wherein an ionic liquid (a) is used as an operating liquid, and wherein two different materials (c, d) of the compressor (100) are brought in contact with the ionic liquid (b) and form an electrochemical element. In order to partially balance a voltage (U) of the electrochemical element at the compressor (110), a counter voltage (U.sub.G) is applied. The invention further relates to such a compressor (100).

Protecting a hydrocarbon pump from excessive flow rates in a hydrocarbon fluid system comprising an electrical motor for driving the pump. For each of a plurality of gas volume fraction values of the hydrocarbon fluid, establishing a maximum torque limit for the pump by mapping the maximum allowable torque of the pump as a function of the differential pressure, thereby creating a plurality of maximum torque curves, each representing the maximum torque limit for a unique gas volume fraction value. Establishing a master maximum torque curve which represents the maximum torque limit for all gas volume fraction values. Monitoring the torque of the pump and the differential pressure across the pump. Based on the monitored differential pressure and using the master maximum torque curve, establishing a maximum allowable torque for the pump. Taking action if the monitored torque exceeds the established maximum allowable torque.

A pump for conveying a fluid includes a casing with a casing inner wall, a pump interior, an inlet opening, an outlet opening, a displacement assembly, and a radial protective element arranged in the pump interior in order to line at least one radial section of the pump interior, the radial protective element bearing against a radial section of the casing inner wall. A fastening element is provided which can be arranged in a fastening position in which the fastening element bears against an edge of the radial protective element and in the process fastens the radial protective element in the pump interior, wherein the fastening element has a longitudinal extent which extends from a first axial end of the pump interior along a recess arranged in the casing inner wall.

The pump includes a pumping chamber within a sealed internal chamber, a pump inlet connected to the pumping chamber, a pump outlet connected to the pumping chamber, and a rotational pumping element configured to pump the corrosive fluid from the pump inlet to the pump outlet. The rotational pumping element is within the pumping chamber. The pump includes a drive shaft for driving the rotational pumping element. The drive shaft is completely within the sealed internal chamber. The drive shaft is configured for magnetically coupling to an external motor. A pump housing forms the sealed internal chamber. The rotational element, the pumping chamber, and the pump housing are formed from any one a conductive plastic, a non-conducting plastic with conducting particles, a semi-conducing ceramic, and combinations thereof. The drive shaft is formed from the semi-conducting ceramic.

The pump includes a pumping chamber within a sealed internal chamber, a pump inlet connected to the pumping chamber, a pump outlet connected to the pumping chamber, and a rotational pumping element configured to pump the corrosive fluid from the pump inlet to the pump outlet. The rotational pumping element is within the pumping chamber. The pump includes a drive shaft for driving the rotational pumping element. The drive shaft is completely within the sealed internal chamber. The drive shaft is configured for magnetically coupling to an external motor. A pump housing forms the sealed internal chamber. The rotational element, the pumping chamber, and the pump housing are formed from any one a conductive plastic, a non-conducting plastic with conducting particles, a semi-conducing ceramic, and combinations thereof. The drive shaft is formed from the semi-conducting ceramic.

A method of protecting a hydrocarbon pump (6) from excessive flow rates in a system for pumping a hydrocarbon fluid, which system comprises said pump and an electrical motor (10) for driving the pump. The method comprises the steps of: for each of a plurality of gas volume fraction values of the hydrocarbon fluid, establishing a maximum torque limit for the pump by mapping the maximum allowable torque of the pump as a function of the differential pressure across the pump, thereby creating a plurality of maximum torque curves (4), each representing the maximum torque limit for a unique gas volume fraction value; from the plurality of maximum torque curves (4), establishing a master maximum torque curve (5) which represents the maximum torque limit for all gas volume fraction values; monitoring the torque of the pump and the differential pressure across the pump; based on the monitored differential pressure (DP) and using the master maximum torque curve, establishing a maximum allowable torque (T) for the pump; and taking a predetermined action if the monitored torque exceeds the established maximum allowable torque (T), e.g. raising an alarm and/or shutting down the system.