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UltraSonic Cleaner
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Ultra Sonic cleaners are used for
a variety of purposes such as: Automotive parts, Calligraphic
pens, Chemical mixing, Computer plotter pens, Homogenization's,
Hypodermic needles, Ink jet cartridges, Jewelry, Laboratory glassware
and apparatus, Lenses, Nozzles, Printed circuit boards, Sieves,
Small components, and a variety of other laboratory ware.
The technique is used to accelerate reactions, treat wastes,
ores, and minerals, disperse fine particles and suspend slurries,
disrupt biological cells and tissues, homogenize and emulsify,
and clean surfaces and porous materials. This work entails "blasting"
liquids, usually water, with powerful sound energy, unlike sonar,
imaging, measuring, or non-destructive testing, in which the subject
is not altered by the sound energy. Most such work is done at
very high frequencies, far above human hearing. Processing, on
the other hand, works at frequencies just above human hearing,
20 to 40 kHz (20,000 to 40,000 cycles per second).
A Non-Technical Explanation of "Cold Boiling - "Ultrasonic
Cleaning" means "blasting" liquids, usually water,
with very intense sound at high frequency, producing very good
mixing and powerful chemical and physical reactions. The process,
called "cavitation", is sort of "cold
boiling" and results from the creation and collapse of zillions
of microscopic bubbles in the liquid. "Cavitation" or
"cold boiling". To move water molecules apart,
a gas is required, and the gas is steam of water. A steam bubble
is normally created by heating above the boiling point (212º
F or 100º C). But by fast jiggling, not by
heating, so the water is "cold boiled"!
Now there is a steam bubble wandering around in a cold
liquid, and that just can't be! The steam has to condense (the
way steam from a kettle or hot shower frosts a glass or mirror)
and that leaves an empty space behind, a "void" or "cavity",
where the steam was. The surrounding water molecules rush in to
fill that cavity; when they reach the center of the cavity, they
collide with each other with great force. This is called "cavitation".
That makes the molecules bounce back, creating a "shock wave"
which runs outward from the collapsed bubble just like ripples
in a pond when you throw in a pebble. The shock wave can wear
away metal; like the edges of an outboard motor propeller. Where
shock waves meet each other, they can cause more steam bubbles
to occur and collapse, creating even more cavitation.
