Through test

the variable mutual relationship among inlet temperature of working water

flow rate of leaked air into negative pressure vaccum system

performance of condenser

and flow rate of extracted air by the water-ring vacuum pump equiped for home-made 300 MW uint has been obtained.Study shows that the inlet temperature of working water has decisive effect upon the flow rate of extracted air by the water-ring pump under condition of constant flow rate of the leaked in air

decrease of inlet temperature for the working water can efficiently improve the problem of lower extracting capability in using water-ring pump and poor vacuum in operation of the unit during summer season.The said method has reference significance for enhancing air-extracting capability of other type air-extracting equipments.