Last month we discussed what aqueous cleaning is, and this month we are going to delve a little deeper into a specific cleaning option by explaining what ultrasonic cleaning is and what it involves.
Ultrasonic cleaning uses ultrasound and a cleaning solvent to clean a specific item. People are most familiar with ultrasonic cleaning in a couple of its uses: jewelry and dental instrumentation. In both of these cases there are delicate items or precision instruments involved and often parts with small crevices that must be cleaned. These items are immersed in a liquid that is flooded with high frequency sound waves, and both act in concert to remove dirt and debris. Ultrasonic cleaning does not use scrubbers or brushes because the sound waves themselves act as brushes.
How do sound waves act as brushes? Well, that’s interesting. Ultrasonic energy enters the cleaning tank the parts are immersed in and causes minute bubbles to form and collapse very quickly. This process is called cavitation and involves the creation of positive and negative pressure waves. These waves create bubbles that grow larger and larger and eventually implode, aiming heat, pressure, and velocity of the energy released at whatever hard surface is nearby. This energy acts as a tiny jet, or brush, and is excellent at dislodging whatever dirt may be on the item being cleaned.
How large and how powerful the bubbles will be depends on the frequency of the ultrasonic waves, and those are determined by which kind of transducer the parts cleaner utilizes. A transducer is a device that converts one form of energy into another. With ultrasonic cleaning the transducers convert electricity into pressure: those positive and negative waves mentioned above. The size and effectiveness of the bubbles created is determined by the frequency of the transducer, and most often with parts cleaners this falls within the range of 20 to 80 kHz.
AEC’s ultrasonic parts washers are designed with various stages of cleaning for best performance. These include ultrasonic washing, ultrasonic rinsing, and regen drying. With this kind of parts cleaner it is possible to get deep and probing cleaning that will remove a variety of contaminants including dust, dirt, oil, grease, mold release agents, blood, and even fingerprints from materials like glass, metal, plastic, and rubber without the use of harsh solvents.
If your company is in need of an effective, efficient, and environmentally friendly parts cleaning solution, we at AEC Systems would love to discuss your options – including ultrasonic cleaning – with you.