Can cavitation in pumps and compressors be detected using ultrasound?

Yes. Cavitation can generate ultrasonic signals that can be detected and evaluated using the SONAPHONE.

For the inspection, structure-borne sound signals are recorded at a suitable measurement point on the machine. The BS20 or BS40 structure-borne sound sensors can be used for this purpose.

How is the measurement performed?

The sensor is coupled to a suitable point on the machine housing. The SONAPHONE detects the resulting structure-borne sound signals and displays them, for example, as:

• ultrasonic level,
• level curve,
• spectrogram.

The ultrasonic signal can also be made audible.

Changes in the signal may indicate a change in the machine or process condition.

How is cavitation assessed?

For condition assessment, it is particularly useful to compare measurements taken under comparable operating conditions.

Wherever possible, use:

• the same measurement point,
• the same sensor,
• the same coupling method, and
• comparable operating conditions.

This makes it possible to identify changes in the ultrasonic signal over time and use them for condition monitoring.

Ultrasonic inspection provides indications of cavitation or changes in machine condition. A definitive determination of the cause should always take the machine's operating parameters into account and, where necessary, be supplemented by additional diagnostic methods.