Impeller for centrifugal pumps

US4208169A · kind A · utility

Assignee

• Klein, Schanzlin & Becker Aktiengesellschaft · DE

Inventors

• Karl H. Becker · Riverview, US
• Hans-Dieter Knopfel
• Alexander Nicklas · Dirmstein, DE
• Peter Hergt · Ludwigshafen, DE
• Engin Diler · Bischofswerda, DE

Key dates

• Filing date: May 10, 1977
• Grant date: Jun 17, 1980
• Expiry date: May 10, 1997

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F04D29/245
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A radial or semiaxial impeller for centrifugal pumps has an annulus of vanes whose inlet edges are disposed at the periphery of a circle and are bounded by convex transition surfaces having small radii of curvature. The inner portions of the suction sides of vanes are bounded by flat or slightly curved surfaces which merge gradually into concave surfaces bounding the outer portions of the respective suction sides. The length of each flat or slightly curved surface is between 3 millimeters and the vane pitch. The ratio of the radii of curvature of transition surfaces at the inlet edges of the vanes to the vane pitch is between 0.0035 and 0.04 and/or the ratio of these radii to the average thickness of the inlet portion of a conventional vane is between 0.04 and 0.50. Such construction of the vanes reduces the likelihood of excessive erosion as a result of cavitation.