Hofmann EasyBalancer EB 3500 - Unbalance of Rigid Rotors; Static Unbalance

EasyBalancer EB 3500 Vibration testing and balancing device - Setup instructions
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3.7.6 Unbalance of rigid rotors
Static unbalance If a rotor has a single unbalance in the radial plane in which its
centre of gravity lies, this is referred to as a static unbalance .
Static unbalance occurs, for example, when the main axis of in-
ertia of a rotor is shifted parallel to the axis of rotation .
Fig. 3-9: Static unbalance
If the rotor is symmetrically constructed, a static unbalance caus-
es equally high dynamic bearing forces.
Only one correction plane is required to correct a static unbal-
ance . However, if this correction is not done in the plane of
the rotor’s centre of gravity, an additional moment unbalance
will result.
1 Unbalance U
2 Main axis of inertia
3 Axis of rotation
4 Mass compensation
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2
3
U = M * e
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