Multistage pump is a pump with two or more than two impeller. Usually the structure has the spiral case type multistage pump and the sectional type multistage pump.
The spiral case type multistage pump is generally used in the open type structure to facilitate the maintenance, and is advantageous for the symmetrical arrangement of the impeller, and reduces the axial force on the rotor. But the structure of technology and less: Series increasing, the shape of the pump body and cover more complex, pump dimensions is large, especially level and need to configure some level between channel, the pump complex shape. And when the series more, head higher, the opening of the sealing surface is more difficult. Based on these factors, the wide application of this structure is limited.
Segmented multi-stage pump compact structure, is conducive to improve the degree of standardization, generalization. Because of the structure of the pump head depends on the pump series, so the head of the pump range is wider.
