Abstract: Multiple stage centrifugal pumps have a plurality of rotors arranged on a drive shaft are shown. At least one rotor is formed as a hollow shaft which is rotatably journalled on the drive shaft and which rotates with a speed of rotation n2 which is different from the speed of rotation n1 of the drive shaft. The hollow shaft is driven by a mechanical converter which takes up mechanical power from the drive shaft in the housing and gives it off at a different speed of rotation n2 to the hollow shaft in such a manner that the speed of rotation of a rotor of the first stage is lower in order to produce a lower NPSHR value for the multiple stage pump.