The invention discloses a molded line design method for a
corrosion-resistant multi-cavity plum pump. The molded line design method comprises the following steps that S1, molded line parameters are designed; s2, designing an outer rotor; and S3, designing an inner rotor. The design method is simple in step, the molded lines of the inner rotor and the outer rotor can be accurately meshed in the whole running process, a suction cavity and a
discharge cavity can be separated through meshing points, stable running and high efficiency of the pump are ensured, the inner rotor and the outer rotor rotate around the centers of the inner rotor and the outer rotor, a
closed cavity is formed through molded line combination, and gas compression is achieved; meanwhile, the molded line overcomes the defects that a traditional circular rotor air cylinder molded line is simple, the area
utilization rate is low, flow fluctuation is too large, and the defect that an asymmetric structure needs
dynamic balance is overcome.