The slurry pump guarantees the mixture of solid particles containing dregs and water. But in principle, the slurry pump is a kind of centrifugal pump, which is mainly used in converter dedusting water, blast furnace gas washing water, continuous casting turbid circulating water and rolling turbid circulating water systems. Shaft seal mode. The shaft seal installation plays a sealing role between the pump body and the pump shaft. It can prevent air from entering the pump and a large amount of water from leaking out of the pump. The sealing method of centrifugal slurry pump usually adopts the auxiliary impeller plus packing seal, and the auxiliary impeller plus packing seal is a hydrodynamic seal. The head generated by the auxiliary impeller is used to resist the leakage of liquid at the outlet of the impeller. At the same time, the cover plate of the impeller is used to set the back blade with water sealing ring and packing to avoid the air entering, and the back blade and water sealing ring are used to reduce the pressure at the packing, so as to avoid impurities entering the seal. Function.