A liquid band vacuum pump is easy to operate and is utilized in several applications across various Liquid-Ring Vacuum Pump china industries. A liquid band pump works together with a sealant needed in its operation. This liquid could be water, oil or any various other solvent which is usually rotated by an impeller within the casing of the pump.
As the shaft turns, a liquid ring is created by 
the centrifugal force produced by the rotating impeller. This power holds the liquid band against the inner wall of the pumping chamber. Since the impeller is situated eccentric to the pumping chamber, the depth of access of the blades in to the liquid ring decreases and raises as the impeller rotates. This creates increasing cellular volume on the inlet slot side, creating vacuum.
On the discharge slot side, the impeller cell volume decreases as the blades move further into the liquid band. This increases the pressure until discharge takes place through the discharge port.
A continuous flow of clean sealing liquid comes to the pump via the sealing-liquid inlet.
Regarding the two-stage liquid ring pump, the discharge from the initial stage will not discharge to atmosphere. Rather, the first stage discharges through the manifold leading to the second stage in addition to through a discharge slot positioned in the intermediate plate between your first- and second-stage impellers.