Description: Rotor resonant frequency calculated assuming that the rotor is supported only in the bearings and that the bearings have infinite stiffness; Name: crit speed (dry)
Description: Rotor resonant frequency calculated considering the additional support and damping produced by the action of the pumped fluid within rotor  ; Name: Wet critical speed
Description: norm describing the material. The material number is taken from this norm. Type and number of the norm with issue year and issue month must be given; Name: Reference norm material of the travel wheel