Intake device for a vertical pump (86, 136) being an axial pump or a semi-axial pump, comprising: - a fluid inlet, - a fluid outlet which is aligned perpendicular to the fluid inlet and - a flow channel which connects the fluid inlet with the fluid outlet and which comprises a first section and a second section wherein the first section directly follows the fluid inlet and wherein the second section in which the direction of the flow channel changes to the fluid outlet by forming a bend, wherein the cross section of the flow channel in the area of its first section changes from a circular cross section at the fluid inlet to an elliptical cross section, wherein the cross section of the flow channel in the area of its second section changes from an elliptical cross section to a circular cross section at the fluid outlet and wherein the diameter of the fluid outlet is smaller than the diameter of the fluid inlet, wherein the intake device comprises a mounting flange radially surrounding the fluid outlet and configured for a loose installation of an axial pump on top of the mounting flange, wherein means for positive form locking are arranged on the mounting flange and protrude in the axial direction of the fluid outlet for preventing the axial pump from rotating around its middle axis, or wherein the intake device comprises a bearing flange being flange-mounted to the fluid outlet for supporting a semi-axial pump, wherein the bearing flange on its side which directly points away from the intake device comprises a ring flange, such that the semi-axial pump is installed loose on top of the ring flange, wherein means for positive form locking are arranged on said ring flange which protrude in the axial direction of the bearing flange for preventing the semi-axial pump from rotating around its middle axis. - a fluid inlet, - a fluid outlet which is aligned perpendicular to the fluid inlet and - a flow channel which connects the fluid inlet with the fluid outlet and which comprises a first section and a second section wherein the first section directly follows the fluid inlet and wherein the second section in which the direction of the flow channel changes to the fluid outlet by forming a bend, wherein the cross section of the flow channel in the area of its first section changes from a circular cross section at the fluid inlet to an elliptical cross section, wherein the cross section of the flow channel in the area of its second section changes from an elliptical cross section to a circular cross section at the fluid outlet and wherein the diameter of the fluid outlet is smaller than the diameter of the fluid inlet, wherein the intake device comprises a mounting flange radially surrounding the fluid outlet and configured for a loose installation of an axial pump on top of the mounting flange, wherein means for positive form locking are arranged on the mounting flange and protrude in the axial direction of the fluid outlet for preventing the axial pump from rotating around its middle axis, or wherein the intake device comprises a bearing flange being flange-mounted to the fluid outlet for supporting a semi-axial pump, wherein the bearing flange on its side which directly points away from the intake device comprises a ring flange, such that the semi-axial pump is installed loose on top of the ring flange, wherein means for positive form locking are arranged on said ring flange which protrude in the axial direction of the bearing flange for preventing the semi-axial pump from rotating around its middle axis.