What are the differences between different frequencies of ultrasonic welding machines? 

 Ultrasonic welding machine oscillates high frequency signal from transducer to mechanical energy through oscillating circuit. The energy is transmitted to the workpiece through welding head. With hundreds of thousands of vibrations per second and pressure, the workpiece's joint surface melts after severe friction. The transient pressure maintained on the workpiece after vibration solidifies the two weldments as a whole by means of molecular linkage. 

Advantages of ultrasonic welding machine:

1.焊接无火花，环保安全。

1. No spark welding, environmental protection and safety.

2.接近冷态加工、工件不退火、五氧化痕迹。

2. Close to cold processing, no annealing of the workpiece, trace of pentoxide.

3.熔合强度高、焊接材料不熔融，不脆弱金属特性。

3. High fusion strength, non-melting welding materials, non-fragile metal characteristics.

4.超声波焊接快速，每次焊接时间0.01-9.99秒。

4. Ultrasonic welding is fast, each welding time is 0.01-9.99 seconds.

5.对焊接金属表面要求低，氧化或电镀均可焊接。

5. Low requirements for welded metal surface, oxidation or electroplating can be welded.

6.超声强度可承受大的拉力、高压力。

6. Ultrasonic strength can withstand large tension and high pressure.

7.经济，省成本，省人工，不用螺钉、胶水。

7. Economical, cost-saving, labor-saving, no screw, glue.

8.产品品质可达到不漏水、不漏气，可气密等超声波焊接效果。

8. the product quality can achieve no leakage, no gas leakage, gas tightness and other ultrasonic welding effect.

    According to different frequencies, ultrasonic welding can be divided into 40khz, 35khz, 28khz, 20kHz and 15khz. The differences between different frequencies of ultrasonic welding are as follows:

1. Different uses

The higher the frequency, the smaller the amplitude, and the smaller the corresponding power. So the high frequency (40khz/35khz) welding machine is used to weld plastic parts with small size and precision; the 28kHz welding machine is mostly used for hand spot welding machine; the 20khz/15khz ultrasonic welding machine is used to weld large and complex plastic parts.

2. Different sizes of ultrasonic moulds

Semi-wave welding head is the most common type of ultrasonic die. The die sizes of different frequency ultrasonic welding machines are different. 40K die (7cm), 35kHz die (8cm), 28kHz die (10cm), 20kHz die (13cm), 15KHz die (17cm). Measuring the length of the ultrasonic mould is also one of the important indexes to judge the frequency.

3. Different structures

The sound production structure of high frequency welding machine (40 khz, 35 khz, 28 khz) is split (transducer + horn is a single component), desktop ultrasonic welding machine (20 khz, 15 khz) is integrated (transducer + horn is a whole component).