water ring vacuum pump working principle:
The water-ring vacuum pump is a kind of coarse vacuum pump. The limit vacuum it can obtain is 2000-4000 Pa. The series air ejector can reach 270-670 Pa. Water ring pump can also be used as compressor, called water ring compressor, is a low-pressure compressor, its pressure range is 1-2X105 Pa meter pressure.
Water-ring vacuum pumps were originally used as self-suction pumps, and then gradually used in petroleum, chemical, mechanical, mining, light industry, medicine and food and many other industrial sectors. In many industrial processes, such as vacuum filtration, vacuum water diversion, vacuum feeding, vacuum evaporation, vacuum concentration, vacuum moisture regain and vacuum degassing, water ring pump has been widely used. Due to the rapid development of vacuum application technology, water ring pump has been paid much attention in obtaining coarse vacuum. Because the gas compression in the water ring pump is isothermal, it can extract flammable and explosive gases, in addition, it can also extract dust, water-bearing gases, so the application of water ring pump is increasing.
The pump body contains proper amount of water as working fluid. When the impeller rotates clockwise in the diagram, the water is thrown around by the impeller. Due to the centrifugal force, the water forms a closed ring which is approximately equal to the thickness of the pump cavity. The inner surface of the lower part of the water ring is exactly tangent to the hub of the impeller, and the upper inner surface of the water ring is just at the tip of the blade (in fact, the blade has a certain insertion depth in the water ring). At this time, a crescent space is formed between the hub and the water ring of the impeller, which is divided into several small cavities equal to the number of blades. If the lower zero of the impeller is taken as the starting point, the area of the small cavity increases from small to large when the impeller rotates 180 degrees, and is connected with the suction port on the end face. At this time, the gas is sucked in, and the small cavity is isolated from the suction port when the suction is finished. When the mouth is connected, the gas is discharged out of the pump.
In summary, the water ring pump is to achieve suction, compression and exhaust by changing the volume of the pump chamber, so it belongs to variable volume vacuum pump.