In cases with high proportions of vapor on the suction side condensing in the pump
during compression it may happen that the pump lacks in sufficient inert gases,
and towards the end of compression there is not enough compressible media. Then,
cavitation on the pressure side occurs. As is known, cavitation on the suction side
occurs when the liquid ring vacuum pump is operated at a suction pressure close to
the boiling temperature of the operating liquid belonging to this pressure.
To avoid cavitation on the pressure side, the pump must always deliver as much
gas – mainly inert gases – as corresponds to the suction capacity of the pump at the
lowest suction pressure