Intensive cleaning (28kHz)
28kHz ultrasonic cleaners have strong scrubbing action. These ultrasonic cleaners are used to remove highly-bonded contamination such as burned carbon on an engine cylinder head. These machines remove larger particles more efficiently than higher frequency systems, and tend to remove coatings more effectively. 28kHz ultrasonic cleaners are not suitable for sensitive metals: erosion will tend to etch the surface of certain parts, such as highly-polished or machined aluminum components.