Static Characteristics Analysis of Shaft Rotor of Vertical Long-Shaft Fire Pump Under the Connection of Different Shaft Lengths

Abstract

In this paper, a vertical long-shaft fire pump XBC18-178-240LC3 was taken as the research object to study the static characteristics of the pump rotor-shaft system under different shaft length connection. To analyse the influence of the length and number of the intermediate shaft section of the pump shaft on the deformation and equivalent stress of the shafting rotor, three shafting rotor models Z4(modified model), Z5(original model) and Z6(modified model) were designed, and then the static characteristics of them were analysed and compared under four operating conditions of 0.65Q d(0.65 times design flow),1.0Q d, 1.2Q d and 1.4Q d by numerical simulation. The results suggested that the changed rules of the three models' deformation and equivalent stress were basically the same. After the rated operating condition, the maximum deformation of the impeller of Z5 model was smaller than that of the Z4 and Z6 models. Under the four operating conditions, the maximum equivalent stress of the impeller of Z5 model was the smallest. This showed that the length and number of the intermediate shaft section affected the deformation and equivalent stress of the shaft rotor. Therefore, Z5 model was selected as the best rotor structure design scheme.