Reciprocating compressor valve in good condition
The advantage of ultrasound spectral analysis is that the inspector can hear and see the sound sample as it plays. Here is a typical good compressor valve. Note the distinct “open” “close” of the valve.
Reciprocating compressor valve in leaking condition
This is an example if a leaking reciprocating compressor valve. It does not close as sharply as in the sample of the “Good” reciprocating valve. You will also note the longer “open” segment in the time series.
Cavitation effect in a valve
This is an example of cavitation in a valve. Cavitation is the formation and implosion of cavities in a liquid (similar to bubbles) usually on the low pressure side of a pump or valve. Cavitation is a significant cause of wear (surface fatigue) that can lead to a failure condition. The most common examples of this kind of wear are pump impellers and bends when a sudden change in the direction of liquid occurs.