Ultrasonic Cleaning 101: What Are Ultrasonic Waves and How Do They Clean?

How does ultrasonic cleaning work? Ultrasonic cleaning systems use ultrasonic waves to clean parts, tools, and equipment quickly, thoroughly and effectively. Typical features of the ultrasonic cleaning system include an ultrasonic generator, a transducer, and a cleaning tank.

The ultrasonic generator generates an electric signal at the required ultrasonic frequency, which ranges from 26 kHz to 200 kHz; it may be designed for a single frequency or a frequency range.

The transducer is usually submerged in the cleaning solution. Once it receives the electric signal from the ultrasonic generator, it converts the signal into ultrasonic waves in the cleaning solution. When this happens, the transducer's metal plate vibrates at the ultrasonic frequency and fills the liquid with the ultrasonic waves.  High performance industrial ultrasonic cleaners use plain water to clean but adding a mild detergent and heating the solution can assist with some contaminants.

The cleaning tank holds the items to be cleaned, the cleaning liquid and the transducer. It may include a basket to keep the items from touching the tank's walls and bottom, and may also include a heater to warm the liquid.

While all industrial ultrasonic cleaners work in the same way, the operating frequency will influence what kinds of parts can receive the most effective cleaning. Generally lower frequencies are good for heavy dirt and contamination on harder surfaces while higher frequencies are most effective for delicate cleaning applications on softer surfaces.

The ultrasonic waves effectively and thoroughly remove contaminants from the surface of the being cleaned through the action of the cavitation bubbles. The ultrasonic waves produced by the generator travel in the cleaning solution, the peaks, and troughs becoming areas of high and low pressure. The bubbles form and the collapse under low and high pressure, respectively, creating the scrubbing action that lifts the impurities from the surface.

Low frequencies (26 kHz to 38 kHz) create comparatively large bubbles that provide a more intense and robust cleaning action for certain items like glass and metal tools. High frequencies (100 kHz and higher) gives off a gentler cleaning action -- ideal for cleaning delicate tools and parts such as solar cells and medical equipment. Choosing the correct frequency and other features in the ultrasonic cleaning system is critical to ensure optimal cleaning performance.

For more details read the complete article titled “Ultrasonic Cleaning 101: What are Ultrasonic Waves and How Do They Clean?” If you have questions or would like a free quote, send an email to info@kaijo-shibuya.com or call 408-675-5575.