# Critical speed

Calculation of the bending characteristic vibration frequency of individual shafts, with or without additional masses. The bearing stiffness and the housing rigidity can be taken into account by entering the rigidity values in the graphic shaft editor.

Calculation of any number of critical speeds (up to ten in one calculation procedure)
Any number of line masses
Presentation on the screen and printout of the bend bending vibration lines
For support profiles the critical bending speeds are determined in two main planes.
Gears can automatically be taken into account as masses. In this process KISSsoft takes the mass and moments of inertia of the gear sitting on the shaft into account.
The gyroscope effect of large centrifugal masses is taken into account. The critical bending speeds for standstill (natural frequency), the synchronism and reverse rotation are calculated. In synchronous ganging the unbalanced mass excites the bending vibrations because the angular velocity of the rotating shaft and the angular velocity of the revolving shaft mid point are the same. The synchronous reverse rotation is usually technically irrelevant. The moment of inertia of all shaft elements can also be included in the calculation if desired.
Calculation of the rotary characteristic vibrations of shafts

Calculation of the critical rotary natural frequencies of individual shafts on the basis of a continuous beam model.
Calculation of up to ten rotary natural frequencies in one procedure.
Presentation of the vibration mode on the screen and printer