More Spectra and Sounds

This graph shows excess gear tooth friction in a large 11 RPM bull gear. The gear cracked shortly after these readings were taken.

This graph shows the low level of ultrasound from the motor side bearing of a high-speed overhung cantilever fan. The sound is barely audible.

This trace shows the fan side bearing, approximately one foot away, on the same fan. The excessive ultrasound was due to a bent fan shaft.

Click your browser's back button to return to the previous page.