The ZX and ZW series self-priming pumps produced by our factory are energy-saving pump products developed after absorbing, digesting and improving the relevant technical data at home and abroad. The pump is a self-priming centrifugal pump, which has the advantages of compact structure, convenient operation, stable operation, easy maintenance, high efficiency, long life, and strong self-priming ability. There is no need to install a bottom valve in the pipeline. It is only necessary to ensure that there is a quantitative suction liquid stored in the pump body before work; The unique design of the impeller flow path, like a general self-priming clean water pump, does not need to install a bottom valve and irrigation, and can also absorb and discharge liquid containing large particles of solid and long fiber impurities, thus simplifying the pipeline system and improving working conditions.

Working principle and structure description
The pump adopts the pump body structure with axial liquid return. The pump body is composed of a suction chamber, a liquid storage chamber, a scroll chamber, a liquid return hole, and a gas-liquid separation chamber. After the pump is started normally, the liquid stored in the impeller paddle suction chamber and the air in the suction pipeline are inhaled together and completely mixed in the impeller. A white foam belt with a certain thickness and a high-speed rotating liquid ring are formed on the edge. The gas-liquid mixture enters the gas-liquid separation chamber through the diffusion tube. At this time, due to the sudden decrease of the flow rate, the lighter gas is separated from the mixed gas-liquid, and the gas continues to rise and discharge through the outlet of the pump body. The degassed liquid returns to the liquid storage chamber, and enters the impeller again through the return hole, mixes with the gas sucked from the suction pipe inside the impeller again, and flows to the outer edge of the impeller under the action of the high-speed rotating impeller. As this process goes on again and again, the air in the suction line is continuously reduced until the air is exhausted, the self-priming process is completed, and the pump is put into normal operation.
There is also a cooling chamber at the bottom of the bearing body of some pumps. When the temperature of the bearing body exceeds 70°C due to the heating of the bearing, the coolant can be injected into the cooling chamber through any one of the coolant pipe joints and circulated for cooling. The sealing mechanism inside the pump to prevent the liquid from leaking from the high-pressure area to the low-pressure area is the front and rear sealing rings. The front sealing ring is installed on the pump body, and the rear sealing ring is installed on the bearing body. When it affects the efficiency and self-priming performance of the pump, it should be replaced.