Water ring pump operation, to continue to fill the water to maintain the pump liquid seal, but also from the role of cooling, but the pump can cause the degree of vacuum by the pump water temperature limit.
The liquid ring vacuum pump allows the extracted gas to not come into direct contact with the pump housing, so that the impeller is made of corrosion-resistant material when the corrosive gas is aspirated. The pump must be injected into the liquid must not react with the gas from the chemical reaction. For example, when the water can be used to smoke, nitrogen can be used when pumping concentrated sulfuric acid. It should also be noted that the liquid used should not contain solid particles, otherwise, will make the impeller and the shell often wear and reduce the pumping capacity.
Single-stage steam jet pump can only get 90% of the vacuum, if you want to get more than 95% of the vacuum, you can use several steam jet pump in series to use, you can get a greater degree of vacuum.