Ultrasonic cleaning utilizes soundwaves to generate millions of microscopic bubbles that thoroughly wash away residue and particulates within minutes. Engineers describe this very specialized process using some precise vocabulary. Today, JAYCO Cleaning Technologies explains the terminology behind ultrasonic cleaning.
Cavitation bubbles form when the high-frequency sound moves through a liquid, and they’re the key to how ultrasonic cleaning works. These microscopic bubbles are often just microns wide — the size of human red blood cells. Cavitation bubbles implode when they come in contact with a surface, releasing jets of liquid traveling at high speeds.
These tiny bubbles can cause pressures as high as 300 pounds per square inch. High-energy bursts of liquid are what wash particles from the surfaces of each workpiece. Imagine this process occurring millions of times per second over the entire surface of each part. You have spotless parts in just minutes.
Various frequencies of sound waves create cavitation bubbles. Typical frequencies for ultrasonic cleaning hover around 40 kilohertz (kHz). Humans can hear anywhere from 20 hertz to 20 kHz. This means the sound frequencies are above the level of human hearing. Hence, they are referred to as ultrasound (beyond or above hearing). In general, lower frequencies of ultrasound work best for larger parts because lower-frequency sound waves make more powerful cavitation bubbles. Therefore, higher frequencies work best for delicate parts and smaller items since the bubbles are not as robust.
Kilohertz (abbreviated kHz) refers to thousands of cycles per second. Lower frequencies in ultrasonic cleaning tanks approach 25 kHz, so these tanks often have sound-deadening insulation to protect the hearing of workers. You might also see soundproofing cabinets for benchtop washers. Higher frequencies don’t necessarily need sound-deadening measures.
The wave generator is what creates high-frequency sound waves in ultrasonic cleaning. This specialized piece of equipment causes the diaphragm, or a cone-shaped part similar to what you find on an audio speaker, to vibrate at a specific frequency. Instead of vibrating air to make sound, the wave generator and diaphragm vibrates aqueous molecules.
An aqueous medium describes the liquid into which you place your items that need washing. The most common aqueous medium is deionized water, although specialized cleaning solvents also work for ultrasonic cleaning. You might use a degreaser for automotive parts or a glass cleaner for sensitive laboratory equipment.
Our experts at JAYCO Cleaning Technologies can talk to your engineers about how ultrasonic cleaning can benefit your firm. If you have industrial parts that need regular precision cleaning, we may have a solution for you. Contact us online or give us a call at (513) 737-9600.