No matter how good ultrasonic waves are applied to hydrocarbon solvents, if thelarge amount of dissolved gases contained in the liquid are not sufficiently removed, countless visible air bubbles will be generated from the diaphragm surface and will eliminate the ultrasonic waves.
Visible bubbles do not constitute ultrasonic cleaning, but only ultrasonic bubbling.
This is not even 1/10th of the true capability of hydrocarbon-based ultrasonic cleaning. Of course, vacuum degassing in a vacuum container is useless if ultrasonic waves are applied under vacuum depressurization.
The true value of the cavities (microvacuum nuclei) generated by ultrasonic waves is demonstrated
under atmospheric pressure. Atmospheric pressure also plays a role in cleaning power.
Therefore, ultrasonic cleaning should be done under atmospheric pressure except for special purposes. In this case, air immediately enters and dissolves from the surface of the liquid.
In other words, in a proper hydrocarbon ultrasonic cleaner, the basic technology for degassing the liquid in the ultrasonic tank is to understand the air that enters and dissolves from the liquid surface and to control the amount of dissolved gas to an appropriate level.
If this cannot be done, the first basic of precision (rapid degreasing and removal of minute foreign matter)
ultrasonic cleaning using hydrocarbon volume agents has not been achieved.
Anyway, no more foamy ultrasonic cleaning.