Balancer for multistage centrifugal pumps

US6568901B2 · kind B2 · utility

Assignee

• KSB Aktiengesellschaft · DE

Inventors

• Bao-Lian Wang · Bischofswerda, DE
• Bernhard Brecht · Hamburg, DE
• Juergen Schill · Bad Dürkheim, DE

Key dates

• Filing date: Dec 14, 2001
• Grant date: May 27, 2003
• Expiry date: Dec 14, 2021

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F04D29/0416
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A balancing arrangement which is used to relieve or take up axial thrust in a multistage centrifugal pump, having a balancing device with at least one axial gap (8) and at least one radial gap (6,7) and in which a balancing flow is conducted through the gaps, and having an axial bearing which receives remaining axial thrust. Associated with the axial bearing is a cardanic ring (10) which serves to offset alignment errors. Highly reliable operation with only low leakage losses is achieved by configuring the balancing device such that a residual thrust in the direction of the suction side of the pump exists in all operating conditons and the cardanic ring is designed such that it is elastically deformed by the residual thrust and has a spring constant such that the axial gap (s) will close from a maximum width position when the pump is at rest to a minimum width position during operation while still avoiding contact between the surfaces which define the axial gap.