Strength calculation of the pump shaft with a worn impeller

Introduction. This paper presents the study of the impeller wear influence on stress-strain state of a centrifugal pump shaft. In agro-industrial sector, centrifugal pumps are used for watering various agricultural crops. During pumping water, a centrifugal pump impeller is usually a subject to influence of various irreversible physical-and-mechanical and physical-and-chemical processes that can result in a certain reduction in its mass. Materials and Methods. We used a comprehensive approach including the analysis of a sufficient number domestic and foreign publications on the research topic and parametric studies conducted on a laboratory-pumping unit. We had modern vibration-based diagnostic equipment, the mathematical models of loading a pump shaft and a finite-element modeling in APM Win Machine software (Beam module). Results. The comparison of the maximum equivalent dynamic stresses obtained according to the proposed method with existing methods for carrying out the checking strength calculation of a centrifugal pump shaft showed that account of the impeller wear significantly changes picture of stress-strain state shaft. Discussion and Conclusions. The amendments proposed by the author in checking strength calculation of a centrifugal pump shaft will allow estimating its stress-strain state in certain production situations.