Double-volute centrifugal pump

The invention provides a double-volute centrifugal pump. The double-volute centrifugal pump is characterized in that an outlet end of a partition is located in the range between the middle section of a diffusion pipe and the horizontal sections of volutes. By optimizing the position of the outlet end of the partition in the volutes, while radial force of an impeller is effectively balanced, a characteristic curve of the double-volute centrifugal pump is improved, in other words, the lift of small flow points is reduced, the lift of large flow points is increased, the characteristic curve becomes mild from steep, and hydraulic efficiency is improved. According to the preferred scheme, the overflowing sectional area of a partition outer passageway is further increased, the characteristic curve of the double-volute centrifugal pump is milder, the casting difficulty of the volutes is lowered, the casting quality of the surface of the passageway can be improved, and hydraulic efficiency is further improved; and th