Process Engineering Equipment Handbook
This is an illustrated guide to the major equipment found in chemical process plants, for engineers charged with operating, specifying and performing basic troubleshooting on the equipment in their environment.
TABLE OF CONTENTS Process Engineering Equipment Handbook
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Ultrasonic Cleaning [*]
The material presented in this section features models of ultrasonic cleaners that are unique to this manufacturer. Other sources' equivalent models' features should be considered for relevant applications.
Theory of Ultrasonic Cleaning
Everything that makes a sound vibrates, and everything that vibrates makes a sound; however, not all sounds are audible. Ultrasound literally means beyond sound sound beyond the audible spectrum. Considering 18,000 Hz (cycles per second) as an approximate limit of human hearing, ultrasonics refers to sound above 18,000 Hz.
The ultrasonic power supply (generator) converts 50/60 Hz voltage to high frequency 20 or 40 kHz (20,000/40,000 cycles per second) electrical energy. This electrical energy is transmitted to the piezoelectric transducer within the converter, where it is changed to high-frequency mechanical vibration. The vibrations from the converter are amplified by the probe (horn), creating pressure waves in the liquid. This action forms millions of microscopic bubbles (cavities) that expand during the negative pressure excursion and implode violently during the positive excursion. It is this phenomenon, referred to as cavitation, that produces the powerful shearing action at the probe tip, and causes the molecules in the liquid to become intensely agitated.
Detailed description
Power supply Depending on the model, the power supply transforms conventional 50/60 Hz electrical power into high-frequency electrical power at 20,000 or 40,000 Hz. Power supplies are typically rated in watts of output power. It should be noted that using a power supply with a higher wattage rating does not mean that more power...
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