Working principle of liquid ring vacuum pump
The liquid ring vacuum pump is equipped with an eccentric rotor with fixed blades. It is a rotary variable volume vacuum pump that throws the liquid to the stator wall, forms a liquid ring concentric with the stator, and the liquid ring and the rotor blades form a variable volume.
Liquid ring vacuum pump was initially used as a self-priming pump, and then gradually used in many industrial sectors such as petroleum, chemical industry, machinery, mining, light industry, medicine and food.
Liquid ring vacuum pump is widely used in many processes of industrial production, such as vacuum filtration, vacuum feeding, vacuum evaporation, vacuum concentration, vacuum moisture regain and vacuum degassing.
Due to the rapid development of vacuum application technology, liquid ring vacuum pump has been paid attention to in obtaining coarse vacuum.
Since the gas compression in the liquid ring vacuum pump is isothermal, it can extract flammable and explosive gases, as well as dust and water containing gases. Therefore, the application of liquid ring vacuum pump is increasing day by day. When the impeller rotates clockwise in the indicated direction, the liquid is thrown around by the impeller. Due to the action of centrifugal force, the liquid forms a closed ring of approximately equal thickness determined by the shape of the pump cavity.
The inner surface of the upper part of the liquid ring is just tangent to the impeller hub, and the inner surface of the lower part of the liquid ring is just in contact with the top of the blade. At this time, a crescent space is formed between the impeller hub and the liquid ring, and this space is divided into several small cavities with the same number of blades by the impeller.
If the upper 0 °of the impeller is taken as the starting point, when the impeller rotates 180 °, the volume of the small cavity becomes larger from small, and is connected with the suction port on the end face. At this time, the gas is sucked in, and when the suction ends, the small cavity is isolated from the suction port; When the impeller continues to rotate, the small cavity changes from large to small, so that the gas is compressed; When the small cavity is communicated with the exhaust port, the gas is discharged out of the pump.
To sum up, liquid ring vacuum pump realizes suction, compression and exhaust by changing the volume of pump chamber, so it belongs to variable volume vacuum pump.