Redesign and manufacture of a centrifugal pump

Abstract

Pumps, of varying designs, have historically been vital in fluid flow. In Zambia, typical applications could be found in domestic water supplies and industrial applications. Complete pumping units have been designed and manufactured elsewhere. The manufacture of pumps in Zambia has generally involved the production of simpler parts such as volutes and covers while complex parts such as the impeller and diffuser casings are imported. This research work was initiated in the School of Engineering at the University of Zambia (UNZA) to carry out product re-engineering on a widely used pump in Zambia. The objective was to re-design the centrifugal pump, submersible type, which could be produced locally while maintaining its current performance characteristics.Concurrent engineering and CAD-CAM software (MasterCam and SolidWorks) were used'in the design process. The final pump design had fewer parts and the production process has been optimised. The Computer Numerical Control (CNC) technology was used to produce permanent moulds for casting the diffuser casings, impeller and bearing housing.