Knowledge | 2022-02-17

How does ultrasonic cleaning work?


As we all know, ultrasonic cleaning advantage is obvious, so how is ultrasonic cleaning work in the end? Ultrasonic cleaning is the direct and indirect action of the cavitation, acceleration, and direct inflow of the ultrasonic wave on the liquid.  So the dirt layer will disperse, emulsify and peel off to achieve the cleaning purpose. At present, the ultrasonic cleaning machine we used, has more application of cavitation and direct flow.

(1) cavitation: cavitation is the transmission of ultrasonic waves to liquids in the form of high-frequency transformations of compressibility and depressurization at a rate of more than 20,000 times per second. When the pressure is reduced, the phenomenon of vacuum nuclear group bubbles appears in the liquid. When the compression force is applied, the vacuum nuclear group bubbles are crushed under the pressure, resulting in a strong impact force, thus stripping the dirt on the surface of the cleaned object, in order to achieve precision cleaning purposes. In the process of ultrasonic cleaning, the bubbles visible to the naked eye are not vacuumed cluster bubbles, but air bubbles, which inhibit cavitation and reduce the cleaning efficiency. Only when the air bubbles in the liquid are completely removed, the cavitation vacuum cluster bubbles can achieve the best effect.

(2) direct inflow: the phenomenon of ultrasonic waves flowing in the liquid along the direction of sound propagation is called direct inflow. When the intensity of the sound wave is 0.5 w/cm2, the flow velocity is about 10 cm/s. Through this direct flow, the micro-oil dirt on the surface of the cleaned material is stirred, and the cleaning liquid on the surface of the cleaned material also generates convection. The dissolving solution of the dissolved dirt is mixed with the new liquid, thus speeding up the dissolving speed, it plays an important role in the transportation of sewage.

(3) acceleration: the acceleration produced by the propulsion of a liquid particle. For the high-frequency ultrasonic cleaning machine, cavitation is not significant, at this time the cleaning mainly depends on the liquid particles ultrasonic acceleration impact particles for ultra-precision cleaning dirt.