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Runout
Runout is a core engineering term. Definition, usage notes, and a practical example.
Definition
Runout is the wobble of a rotating surface relative to a reference axis.
Why it matters
It affects vibration and wear in shafts, bearing seats, gears, and pulleys.
How it is used
In a design check, first define the relevant load, dimension, material, or flow condition. Then interpret this term by its role in the formula and compare it with limits.
Example
Total runout at a shaft end can be checked with a dial indicator after turning.
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Formulas
No formulas added for this term.