Page 17 - Vibrations

When listening to a machine, the

fundamental frequency is the

number of revs/minute.

A washing machine will have spin

rate of 1,600 revs/minute.

Same as 26 Hz.

However there will lots of other

sounds as well owing to the design

of the bearings.

The bearing on the left has 8 ball

bearings, each will generate is own

fundamental frequency as the shaft

rotates.

Could be slightly different from the others depending on

the precision of manufacture.

Analysing the sounds from rotating machines is not an

easy task, requires great expertise to separate out

vibrations from different components.

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