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: internal volume of a compartment, including the volume of nozzles to the first connection (flange, coupling, screwed connection, weld seam) but excluding the volume of internal structures (e. g. baffles, agitators); Name: Filling volume of the equipment