METHOD OF CONTROLLING OPERATION OF A COMBINED SET CONSISTING OF CENTRIFUGAL PUMN AND VACUUM PUMP AS GAS SEPARATING CENTRIFUGAL PUMP

摘要

The method uses a centrifugal pump impeller (14) and a vacuum pump rotor (44) placed on the same shaft (49). The gas separated in the centrifugal pump from the material to be pumped is discharged from the centrifugal pump. The discharge uses the vacuum pump and a gas outlet duct (26) located between the two pumps. The gas flow in the gas outlet duct between the two pumps is controlled by changing the cross sectional flow area of the gas outlet duct.