Abstract: This essay, by referring to the“ideal liquid”proposes the viscous hydraulic design methods under the conditions of water-moving border of viscous layer of border. The authors deduced viscous distortion equations and transport equations according to water entering conditions of the stamping and welding multilevel centrifugal pumps. This method is applied to the hydraulic design of the multilevel pumps and improved their functions and efficiency.

Key words: Stamping and welding multilevel centrifugal pumps, Theoretical study