Lightweighting of a Centrifugal Pump Casing Through Structural Re-engineering and Simulation

Abstract

In today’s highly competitive market, there is a growing demand for lightweight, cost-effective designs that do not compromise structural integrity or functional performance. In end-suction centrifugal pumps, the casing wall thickness significantly contributes to the overall weight of the product. The study performs design re-engineering of large size pump used for sewage application which add significant value towards product upgradation. This design gives competitive advantage & results into customer satisfaction. In the existing casing design, it is observed that wall thickness is variable which introduces several challenges including uneven weight distribution, potential stress concentration zones, complex manufacturability, difficult quality inspections, and increased material waste, etc. These factors collectively extend the product development cycle and reduce overall efficiency. The study focuses on structural optimization and weight reduction of pump casing and makes it manufacturing friendly design with consistent wall thickness. This is achieved by using simulation driven approach. Simulations / Analysis carried out for pump casing to study the overall stress distribution in the casing region and identify the critical and the non-critical locations. Complementary analytical calculations were also performed to validate and correlate the simulation results, showing strong agreement between both methods.  Based on stress distribution of the existing casing, various design optimization simulations are explored to achieve a uniform wall thickness. Accordingly, design iteration is selected which meets the requirement of stress and factor of safety (FOS) requirements.  This study led to 6% reduction (a saving of over half a ton) in casing weight, achieved consistent wall thickness ensuring structural strength and produce a sustainable, environmentally friendly design by using CAD and simulation/analysis tools. This study also demonstrates the application of meshless technology at the designer level to accelerate the design process as compared to conventional processes.