3. Self-priming centrifugal pumpSelf-priming pump is a single-stage single-priming centrifugal pump that produces self-priming effect by the special structure of the pump itself, which is called a self-priming centrifugal pump. Compared with ordinary centrifugal pumps, there are significant differences in the structure of the pump body: first, the inlet position of the pump is improved, and sometimes the suction valve is installed; The second is to set up a gas-water separation chamber on the outlet side.The self-priming pump outside the pump is a self-priming device added to the pump, such as a vortex pump, a water ring vacuum pump, a jet pump and a hand pump.Compared with ordinary centrifugal pumps, self-priming pumps have compact structure and simple operation, which not only saves the trouble of filling a large amount of water before starting, but also eliminates the low valve of the inlet pipe, reduces the water inlet resistance, and increases the water output of the pump, but the efficiency of the ordinary centrifugal pump of the same specification is 3%~5% lower. Self-priming pumps are mostly used in light and small sprinkler irrigation units and pipeline irrigation units.Electric submersible pumpMaglev submersible pump It has achieved a major breakthrough in the field of submersible pumps in the world, and effectively solved the various drawbacks of traditional submersible pumps: such as low conversion efficiency, high power consumption, limited head, fragile bearings, frequent maintenance, etc. It is widely used in the fields of water supply and drainage, farmland irrigation and water supply in plateau and mountainous areas of industrial and mining enterprises.Maglev submersible pumpIt has changed the manufacturing process of submersible pump with unique patented technology, and the conversion efficiency has reached a shocking new level, creating huge energy saving and consumption reduction benefits.The magnetic levitation submersible pump solves the axial force problem that restricts the development of the world's submersible pump, and the head of the submersible pump has been breakthrough improved, filling the market gap of ultra-high lift (single lift design to thousands of meters) and ultra-large flow (high load) submersible pump; The head and flow curves tend to be flattened. Its conversion efficiency and the highest head of a single machine are among the world's leading positions.