LABEC FXP16M - Manual (Page 5)

LABORATORY EQUIPMENT PTY LTD
ULTRASONIC CLEANERS
General Information
Ultrasonic is the science of sound waves above the frequency of human audibility. In
general, frequencies above 18,000 cycles per second are considered to be ultrasonic.
In ultrasonic cleaning, high amplitude sound waves are introduced into a liquid
cleaning solution. As these sound waves travel through the liquid areas of alternate
positive and negative pressures are created which correspond to the areas of
compression and rarefaction of a sound wave in air.
Air is relatively elastic and conforms in a continuous fashion as a sound wave passes a
given point.
Liquids, however are not elastic (as can be evidenced by hydraulic principal) and are
literally torn apart when a strong rarefaction or negative pressure point is created.
As the liquid is torn apart a microscopic void is created which is called a cavitation
bubble.
For all practical purposes cavitation bubble is an area of vacuum within the body of
liquid and is therefore very unstable and short lived.
When the bubble collapses or implodes, a phenomenon not unlike that of a
thunderclap only on microscopic scales results.
Minute areas of high pressure are created by these “thunderclaps” which break down
the surface boundary layer and enhance chimerical cleaning action.
The advantages of ultrasonic cleaning are:
1.
Cavitation bubbles are extremely small and can reach into areas that the bristle
of a brush could never reach.
2.
Ultrasonic cleaning is fast, accomplishing a better cleaning job in a small
fraction of the time required by other methods.
3.
Ultrasonic cleaning will not damage even the most delicate parts. Parts that
would be bent by simple picking them up in one’s fingers can be cleaned
safely using the gentle yet powerful force of ultrasonic.