Before understanding the frequency difference between 28kHz and 40KHz of ultrasonic cleaning machine, let's know what these two parameters mean respectively: 28kHz refers to 28000 vibrations per minute; 40KHz means 40000 vibrations per minute.

频率是选择超声波清洗机的一大因素，频率也决定了清洗力度。一般的来讲，清洗五金、机械、汽摩、压缩机等行业的清洗多采用28KHZ频率的清洗机。光学光电子清洗、线路板清洗等多采用40KHZ的频率。

Frequency is a major factor in choosing ultrasonic cleaning machine, and frequency also determines the cleaning strength. Generally speaking, 28kHz frequency cleaning machine is used for cleaning hardware, machinery, automobile and motorcycle, compressor and other industries. The frequency of 40KHz is mostly used for optical optoelectronic cleaning and circuit board cleaning.

这是一个错误的说法，而结果恰恰相反，频率越低清洗力度反而更强，清洗效果也更好。不过具体还是看清洗物品，对于大部分产品而言40Khz频率即够了。

This is a wrong statement, but the result is just the opposite. The lower the frequency, the stronger the cleaning force and the better the cleaning effect. However, it still depends on the cleaning items. For most products, 40KHz frequency is enough.

在28khz低频情况下，清洗的液体受到压缩与稀疏作用的时间间隔更长，使气泡能生长到更大尺寸，对清洗工件表面作用力更强。

At 28 kHz low frequency, the time interval between compression and thinning of the cleaning liquid is longer, so that the bubbles can grow to a larger size and exert a stronger force on the surface of the cleaned workpiece.

所以一般大型部件表面或者污物与工件表面结合度较高会选择低频超声波清洗机，但是低频比较容易损伤腐蚀工件表面，所以对那些表面要求较高的零件不宜选择较低的频率。

Therefore, generally, the low-frequency ultrasonic cleaning machine will be selected for the surface of large parts or the combination of dirt and workpiece surface is high, but the low-frequency is easy to damage and corrode the workpiece surface, so it is not suitable to select a lower frequency for those parts with high surface requirements.

大家都知道超声波清洗机的基本原理是基于液体的空化效应，事实上空化效应的强度直接跟频率有关，频率越高，空化气泡越小，空化强度越弱。

As we all know, the basic principle of ultrasonic cleaning machine is based on the cavitation effect of liquid. In fact, the intensity of cavitation effect is directly related to the frequency. The higher the frequency, the smaller the cavitation bubble and the weaker the cavitation intensity.

而且高频穿透力强，适合清洗精密零件，比如电子零件、磁性材料、小型轴承加工;那些集成电路芯片、硅片镀膜的则用更高的频率超声波清洗机;像那些机动车辆的发动机、阀门等大工件一般则用低频率超声波清洗机清洗，而市场用的比较适中的频率是40KHZ。

And high-frequency penetration, suitable for cleaning precision parts, such as electronic parts, magnetic materials, small bearing processing; Those with integrated circuit chips and silicon films use higher frequency ultrasonic cleaning machines; Large workpieces such as engines and valves of motor vehicles are generally cleaned by low-frequency ultrasonic cleaning machine, while the relatively moderate frequency used in the market is 40KHz.