High levels of cleanliness, process stability, fast cleaning times and environmental friendliness do not have to be mutually exclusive. Ultrasonic cleaning makes it possible to achieve excellent levels of cleanliness within a short time, even for geometrically complex components and assemblies. The process is efficient, reliable, extremely gentle on materials and uses minimal amounts of chemicals and energy.
The cleaning effect of ultrasound is based on the physical principle of cavitation. Here, the ultrasonic generator emits electrical signals at a certain frequency, which are then transferred to the liquid as waves of ultrasound via a rod-style or plate transducer. The sonic pressure is characterized by an interplay of positive and negative pressure (vacuum). As a result of the high intensity, microscopic bubbles form in the vacuum phases, which then implode in the subsequent overpressure phase, releasing local shock waves with considerable energy densities. This also triggers microflows in the liquid, which separate and clean away films and particulate matter from the components to be cleaned.
The ultrasonic frequency employed is a key factor in securing the required cleanliness of components. When it comes to ultrasonic cleaning, the rule of thumb is: the lower the frequency, the higher the energy released by the ultrasonic waves. If the frequency is too low, this can damage sensitive cleaning objects, while an excessive frequency leads to a substandard cleaning result.
Lower frequencies (25 kHz to 40 kHz) are generally used for more coarse soiling, while higher frequencies (80 kHz to 120 kHz) are more effective for fine soiling and cleaning parts with very fine structures.
In the high-frequency range, frequencies of around 60 kHz to 200 kHz are used. The ultrasonic frequency of 500 kHz (hypersonic) to 1 MHz (megasonic) is used for non-destructive cleaning of extremely fine structures and highly sensitive microstructures to ensure that these do not suffer any damage.
3 kW ultrasonic generator
The innovative plug-and-play device is fully digital and impresses not only through its maximum process stability and power output, but also its exemplary ease-of-use.
Weber Ultrasonics America
P.O. Box 840
Clarkston, MI 48347-0840
Tel. 001 248 620 5142
Fax 001 248 620 5143