Adding or removing mass cancels unbalanced forces that cause vibration.
Unbalanced rotating mass m at eccentricity e produces centrifugal force mω²e. Static balance uses one plane, dynamic balance two. Add correction masses at calculated angles. Standards (ISO 1940) grade acceptable residual unbalance.
Car tyres are balanced with small weights on the rim.
Unbalance in rotating machines causes vibration that grows with speed squared, which can damage bearings and foundations if not corrected.
Adding or removing mass cancels unbalanced forces that cause vibration.
Unbalance in rotating machines causes vibration that grows with speed squared, which can damage bearings and foundations if not corrected.
It is a standard measure of residual unbalance for a given rotor type and speed, used to set acceptance limits.
Yes, with portable balancers that measure vibration at bearings and calculate the trial mass needed to correct the imbalance.
Typical applications include balancing a washing machine drum to stop it shaking, correcting the balance of a fan rotor in an air handling unit and reducing the vibration of a turbine rotor after a repair.
Study "Modal analysis" first (topic 80 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Single-plane vs two-plane. Balancing machines. Force grows with ω².
Car tyres are balanced with small weights on the rim.
The next topic is "Critical speed of shafts", which builds directly on this one.
It is classed as Advanced in Engineering Mechanics (topic 81 of 106). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Engineering Mechanics.
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