| 摘要 |
PCT No. PCT/EP88/00823 Sec. 371 Date May 17, 1990 Sec. 102(e) Date May 17, 1990 PCT Filed Sep. 9, 1988 PCT Pub. No. WO89/02538 PCT Pub. Date Mar. 23, 1989.An impeller for a centrifugal pump has a hub which is designed to be affixed to the pump shaft. The hub carries a first cover plate which is located at the pressure side of the impeller and supports a series of vanes defining flow channels. The first cover plate is secured to the bases of the vanes and a second cover plate situated at the suction side of the impeller abuts the tops of the vanes and overlies the flow channels. A suction port constituting an individually manufactured component is disposed at the inlet of the impeller and has a section of constant diameter which faces away from the vanes as well as a section of variable diameter which confronts the vanes. The section of variable diameter is connected to the tops of the vanes by a weld seam. The second cover plate overlies that end portion of the suction port having the greatest diameter and is secured to the tops of the vanes in an area between the suction port and the impeller outlet. The cover plates and the suction port are all made of sheet material. |
