Análise de falha de eixo de bomba centrífuga

Abstract

The present work aims to identify cause(s) of failures that occurred in centrifugal pump shafts used in the pumping of iron ore pulp in a large mining plant. The breaks of this type of pump shaft can damage other components, leading to further performance compromises of the equipment. Thus, in the search for the proposed objective, a careful bibliographic review was performed on centrifugal pumps, types of fracture, fatigue and properties of structural steels used in centrifugal pump shafts (ABNT 1045 and ABNT 4140). Studies related to structural integrity, fatigue, failure modes, types of charges and morphology of fractures have also been done. Regarding the experimental part, a careful analysis of the fractured shafts using, among others, the following techniques: visual inspection, conventional mechanical tests (tensile test, Charpy impact test, hardness testing, rotary flexion fatigue test (S-N), micrographic analysis, SEM microfractography and computer simulation. Based on the studies, it was possible to conclude that the breaks of centrifugal pump shafts were motivated by a combination of fatigue potentiated by stress concentrations and occasional overloads.