Liquid ring vacuum pumps are in class of positive displacement pumps. Using the expansion and reduction principle in the cell of impeller blade, they vacuum the gases with a liquid ring. If the appropriate liquid is selected (generally water) all the gases and vapors are moved.
For a liquid ring vacuum pump the final suction pressure is limited with the liquid ring evaporation pressure. During service liquid temperature is 15 ºC at the pump discharge vacuum pressure reaches 25 mmHg (33 mbar).
Liquid ring vacuum pumps have a wide application area in industry. Because of their working conditions are in liquid, they are useful for applications which include moisture like filtration, drying, refrigeration and distillation
Properties:

Safe and efficient operation
able to pump every kind of gas and vapors,
works quiet and reduced vibration
Minimum maintenance with high efficiency,
Low investment and operating casts.
Inner lubrication is not necessary,
The gases which are pump may be saturated steam,
With suitable liquid there is no cleaning problem,
There is not any disorders because there is only one moving part.
There is no leakage with mechanical seal design pumps
Can be used for different applications with proper selection of construction materials and
service liquid

Rotor: Shafts and impellers that are made balance dynamically.
Bearing: With 2 units of bearings.
Drive: Connected to coupling directly or electric motors connected constantly.
Rotating direction : When looking from motor side, clockwise.
Shaft sealing: Standard mechanical seal or With soft packing flushed with service liquid.

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