Abstract: A rotary pump includes a balance drum connected to a pump shaft between a hydraulic unit and the pump shaft, an axial relief passage between a balance drum and a stationary part stationary relative to a pump housing, and a balancing device arranged between the balance drum and the hydraulic unit, the balancing device including a ring-shaped rotary part connected to the pump shaft, and a ring-shaped non-rotary part movable only in the axial direction, the rotary part having an axial face facing the hydraulic unit, the rotary part and the non-rotary part overlap in a radial direction, which is perpendicular to the axial direction, and the non-rotary part movable in the axial direction such that a radial relief passage is open during operation of the pump, with the radial relief passage extending in the radial direction between the rotary part and the non-rotary part.

Abstract: A rotary pump includes a balance drum connected to a pump shaft between a hydraulic unit and the pump shaft, an axial relief passage between a balance drum and a stationary part stationary relative to a pump housing, and a balancing device arranged between the balance drum and the hydraulic unit, the balancing device including a ring-shaped rotary part connected to the pump shaft, and a ring-shaped non-rotary part movable only in the axial direction, the rotary part having an axial face facing the hydraulic unit, the rotary part and the non-rotary part overlap in a radial direction, which is perpendicular to the axial direction, and the non-rotary part movable in the axial direction such that a radial relief passage is open during operation of the pump, with the radial relief passage extending in the radial direction between the rotary part and the non-rotary part.

Abstract: A method for determining the viscosity of a conveying fluid conveyed by a pump, in which an operating value is detected and is fed to an evaluation unit. The method includes providing a reference fluid, recording a reference performance curve resulting from the reference fluid during test operation of the pump at a predetermined operating parameter of the pump, recording an operating performance curve resulting from the conveying fluid during conveying operation of the pump at the predetermined operating parameter of the pump, determining the viscosity of the conveying fluid from a deviation of the operating performance curve from the reference performance curve by a viscosity correction algorithm stored in the evaluation unit.

Abstract: A method of evaluating an operating state of a flow machine includes measuring, in the operating state of the flow machine, a first force component of a bearing force acting on a rotor axle along a first direction using a first force sensor, the first direction lying perpendicularly to the axial direction, measuring a second force component of the bearing force in a second direction using a second force sensor, the second direction lying perpendicularly to the axial direction and being simultaneously perpendicular to the first direction, a resulting force being formed from the first force component and the second force component, preparing a frequency spectrum of the resulting force using a frequency analysis, comparing the frequency spectrum with a reference spectrum, and evaluating an operating state at a predefined operating state of the flow machine.