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: PN (nominal pressure) is an alphanumeric variable for reference purposes, relating to a combination of mechanical and measurement properties of a pipe component. It comprises the letters PN followed by a dimensionless number (according to EN 1333/96.08); Name: Nominal pressure of the muffs, A1