What Does Frequency Mean in Ultrasonic Cleaning?
In ultrasonic cleaning systems, transducers convert electrical energy into high-frequency mechanical vibrations. These vibrations create large numbers of microscopic cavitation bubbles within the cleaning liquid.
The formation and collapse of these bubbles generate energy that helps remove oil, metal chips, production residues and other contaminants from the surfaces of parts. Ultrasonic frequency is one of the main parameters that influences the characteristics of cavitation.
What Is 28 kHz Ultrasonic Cleaning?
28 kHz is one of the ultrasonic frequencies that can be preferred in industrial applications where a stronger mechanical cleaning effect is required.
At lower ultrasonic frequencies, cavitation bubbles can generally generate a stronger mechanical effect. For this reason, 28 kHz can be considered for cleaning heavy contamination, oil, grease and production residues from durable metal parts.
Where Can 28 kHz Be Used?
- Parts contaminated with heavy oil and grease
- Removal of metal chips and production residues
- Durable metal components
- Molds and heavy industrial parts
- Applications requiring a stronger mechanical cleaning effect
However, if the surface of the part is sensitive, the selection should not be based only on cleaning strength. The material and surface characteristics of the part must also be considered.
What Is 40 kHz Ultrasonic Cleaning?
40 kHz is one of the ultrasonic frequencies that can be selected for applications requiring a more controlled and sensitive cleaning process.
It may be particularly suitable for cleaning parts with complex geometries, recessed areas or more sensitive surfaces.
Where Can 40 kHz Be Used?
- Sensitive components
- Parts with delicate surface structures
- Small channels and complex geometries
- Applications requiring more controlled cleaning
- Precision-manufactured components
Frequency alone does not determine the final cleaning result. Ultrasonic power, cleaning chemistry, liquid temperature, transducer placement and the position of the parts inside the tank also affect process performance.
What Is the Difference Between 28 kHz and 40 kHz?
| Feature |
28 kHz |
40 kHz |
| Cavitation effect |
Stronger mechanical effect |
More controlled and sensitive effect |
| Heavy contamination and oil |
Can be advantageous |
Depends on the process |
| Sensitive surfaces |
Should be evaluated carefully |
May be more suitable |
| Complex geometries |
Application-dependent |
Can provide advantages |
This comparison provides a general overview. The final frequency selection should always be based on the technical requirements of the part and cleaning process.
How Is the Right Ultrasonic Frequency Selected?
1. Type of Contamination
Oil, grease, polishing residues, metal chips and other production-related contaminants do not behave in the same way during cleaning. The type and intensity of contamination can influence the required cavitation characteristics.
2. Part Material and Surface Structure
Durable metal parts and components with sensitive surfaces should not necessarily be processed using the same ultrasonic parameters. The suitability of the material for the ultrasonic cleaning process should be evaluated when selecting the frequency.
3. Part Geometry
Holes, channels, blind areas and complex geometries can directly affect the cleaning process. Therefore, not only frequency but also transducer placement and the position of the parts inside the tank should be considered.
4. Ultrasonic Power
Two systems operating at the same frequency may not provide the same cleaning performance. Ultrasonic power relative to tank volume, number of transducers and overall system design also play an important role.
5. Cleaning Temperature
The temperature of the cleaning liquid can affect both the performance of the cleaning chemical and the overall process. Temperature and ultrasonic frequency should therefore not be considered completely independent parameters.
6. Cleaning Chemical
Choosing the correct cleaning chemical is another important part of ultrasonic cleaning performance. If the chemical is not suitable for the part material or contamination type, changing the frequency alone may not be sufficient.
Is a Higher Frequency Always Better?
No. In ultrasonic cleaning, it is not correct to say that a higher or lower frequency is always better.
A stronger mechanical cavitation effect may be required for durable metal parts with heavy oil and production residues. On the other hand, a different frequency may be more appropriate for components with sensitive surfaces or applications requiring more controlled cleaning.
Therefore, the main question should not be “Which frequency is stronger?” but rather “Which frequency is more suitable for this cleaning process?”
Is Transducer Placement as Important as Frequency?
Yes. How ultrasonic energy is transferred into the cleaning tank is one of the important factors affecting system performance.
In addition to the number of transducers, their position on the bottom, side walls or opposing surfaces of the tank can influence the distribution of ultrasonic energy.
For this reason, frequency, ultrasonic power, tank geometry and transducer placement should be evaluated together when designing a professional ultrasonic cleaning system.
Should You Choose 28 kHz or 40 kHz?
For heavy contamination, oil, grease and durable industrial parts, 28 kHz can be considered where a stronger mechanical cavitation effect is required.
For more sensitive surfaces, complex geometries and applications requiring controlled cleaning, 40 kHz may be an appropriate option.
The final selection should consider ultrasonic frequency together with ultrasonic power, transducer placement, temperature, cleaning chemistry, tank geometry and the characteristics of the part.
Frequency Selection in Plussonic Ultrasonic Cleaning Systems
In Plussonic ultrasonic cleaning systems, operating frequency is selected according to the characteristics of the parts being cleaned and the requirements of the process. Depending on the application, 28 kHz and 40 kHz options can be evaluated to create an appropriate ultrasonic cleaning solution.
For selecting the appropriate frequency, power and system configuration for your ultrasonic cleaning process, you can contact Plussonic.
Frequently Asked Questions
What is the main difference between 28 kHz and 40 kHz?
The main difference is the character of cavitation. 28 kHz can be evaluated for applications requiring a stronger mechanical cavitation effect, while 40 kHz can be suitable for more controlled and sensitive cleaning processes.
Is 28 kHz suitable for heavily oiled parts?
28 kHz can be one of the suitable options for durable parts with heavy oil and contamination. However, cleaning chemistry, temperature, ultrasonic power and part structure should also be evaluated together.
Is 40 kHz suitable for sensitive parts?
40 kHz can be preferred in many applications requiring a more controlled ultrasonic effect. The final selection should depend on the material, surface structure and process requirements of the part.
Does frequency alone determine ultrasonic cleaning performance?
No. Ultrasonic power, transducer placement, tank geometry, temperature, cleaning chemistry, part positioning and process time also affect the cleaning result.