Self-priming pump: it has the advantages of compact structure, convenient operation, stable operation, easy maintenance, high efficiency, long service life and strong self-priming ability. There is no need to install a bottom valve in the pipeline, just ensure that there is a fixed amount of liquid in the pump body to work. Self-priming pumps of different materials can be used for different liquids.
2. Self-priming screw pump: simple structure, easy manufacture, large flow, low head loss, high efficiency and convenient maintenance, but low lift and low rotation speed, so it is necessary to set up a speed change device.
Second, the structural principle is different.
1, self-priming pump:
Before starting the pump, fill the pump housing with water (or the pump housing itself has water). After starting, the impeller rotates at high speed, so that the water in the impeller channel flows to the volute. At this time, a vacuum is formed at the inlet to open the inlet check valve, and the air in the suction pipe enters the pump and reaches the outer edge through the impeller channel.
2. Self-priming screw pump:
A pump that uses the rotation of spiral blades to make water spiral up along the shaft. It consists of a shaft, spiral blades and a shell. When pumping water, the pump is placed obliquely in the water, so that the inclination angle of the main shaft of the pump is smaller than that of the spiral blade, and the lower end of the spiral blade is in contact with the water. When the prime mover drives the screw pump shaft to rotate through the speed change device, water enters the blades and rises along the spiral flow channel until it flows out.
Third, the application is different.
1. Self-priming pump: equipped with rocker nozzle, it can also spray water into the air and disperse it into tiny raindrops. It is a good machine for farms, nurseries, orchards and vegetable gardens.
2. Self-priming screw pump: it is mostly used for irrigation, drainage and lifting sewage and sludge.
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