A liquid ring vacuum pump gives definitive advantage over other vacuum pumps as there is only a single rotating part, a multi-bladed rotating impeller to produce an enormously high pressure. This impeller keyed to the pump shaft, is mounted eccentrically in a round pump casing. When the shaft spins the impeller, centrifugal force drives the liquid to the outer edges of the chamber and draws the gas molecules inside through a valve. These molecules of gas are ultimately compressed and pushed out through the exhaust valve. A sealant fluid used in the liquid ring pump forms a ring around the inside of the casing. This ring of liquid acts as a seal. Popular liquid that can act as sealant includes water, ethylene glycol, mineral oil and organic solvents.
Liquid ring pump is known for its longer life and low-cost of maintenance as it does not require many vanes or valves. Besides, because the operation of this pumps hardly causes any noise and vibration, it can be easily installed in most locations.
Other advantages of liquid ring pumps are:
- Uncomplicated design compared to other vacuum pumps
- Can be constructed from any castable metal
- The temperature of the discharged gas shows very little rise
- Easy maintenance