The air-extracting system of dual-pressure condenser is adopting the connection mode with header system

in the case of extracting air from low pressure side of said condenser

the push-out phenomenon appears resulting in deviation of pressure difference between high and low pressrue sides from the designed value

affecting the performance of said dual-pressure condenser.The affecting factors upon said pressure difference have been studied

including the open degree of regulating valve on the air-extracting header of vacuum pump for extracting air and the number of vacuum pumps to be started up etc.

it shows that the regulating valve for extracting air has an optimal open degree which is related to vacuum value in the said condenser.In the event of regulating valve for extracting air is in the optimal open degree

the vacuum pumps adopt operation mode of "two pumps in the operation and one pump in standby" is more economic.