Several problems should be paid attention to in ultrasonic cleaning

- Sep 12, 2018-

First, the choice of power. Ultrasonic cleaning is not necessarily proportional to (power × cleaning time), sometimes with low power, and it takes a long time to remove dirt. And if the power reaches a certain value, the dirt is sometimes removed quickly. If the power is too large, the cavitation intensity will be greatly increased, and the cleaning effect will be improved. However, the more precise parts will also have an etch point, which is not worth the loss, and the cavitation at the bottom of the cleaning cylinder is severe.

Water point corrosion also increases. When using organic solvents such as trichloroethylene, there is basically no problem. However, when water or water-soluble cleaning solution is used, it is susceptible to water pitting corrosion. If the surface of the vibrating plate has been scratched, the bottom of the water is strong. Cavitation corrosion is more serious, so the ultrasonic power should be selected according to the actual use.

Second, the choice of frequency. Ultrasonic cleaning frequencies range from ten to 25 kHz to 120 kHz. Physical cleaning forces caused by cavitation when using water or water cleaning agents are clearly advantageous for low frequencies, typically 25 kHz and 28 kHz. For small gaps, slits, deep hole parts cleaning, high frequency (40kHz, 68KHZ and 80KHZ) is better, even 120KHZ.

Third, the use of cleaning cages. When cleaning small parts, the net cage is often used, and special attention should be paid to the ultrasonic attenuation caused by the mesh. It is better to use a mesh of 10 mm or more.

Fourth, the choice of cleaning fluid temperature. The most suitable cleaning temperature for the water cleaning solution is 40-60 ° C, especially if the low temperature cavitation effect of the cleaning solution is slightly affected during cold weather. Therefore, some cleaning machines are equipped with stainless steel heating tubes in the cleaning cylinder for temperature control. When the temperature rises, cavitation is easy to occur, so the cleaning effect is good. When the temperature continues to rise, the gas pressure in the cavitation increases, causing the impact sound pressure to drop, and the ultrasonic cleaning temperature cannot be too high.

Five. The amount of cleaning fluid and the location of the cleaning parts. Generally, the level of the cleaning liquid is higher than the surface of the vibrator

More than 100mm is preferred. Example 300W, 28kHz liquid surface is about 120mm high; 600W, 28kHz liquid surface is about high

150mm. Since the single-frequency cleaning machine is affected by the standing wave field, the amplitude at the node is small, and the amplitude at the amplitude is large, resulting in uneven cleaning. Therefore, the best choice for cleaning items should be placed at the volatility.