Reasons why ultrasonic welding is not firm
Foreign ultrasonic welding models mostly use 15KZ/20KHZ. In fact, foreign 15KZ/20KHZ can basically meet the welding needs. Domestic ultrasonic welding equipment generally adopts 15KZ/20KHZ/28KHZ35KHZ models. In theory, the larger the amplitude, the better the welding effect. Is it possible to directly choose the ultrasonic welding model with large amplitude?
Let’s talk about the principle of ultrasonic welding first: the high-frequency electric energy converted by the ultrasonic generator is converted into mechanical motion energy of the same frequency again through the transducer, and the mechanical motion energy is transmitted to the ultrasonic welding head through the amplitude modulator device. The mass point vibrates rapidly, and the molecules rub violently during the vibration process, generating a lot of heat. Due to the poor thermal conductivity of plastics, the heat generated by the molecular vibration process is not easy to dissipate at the welding place, so as to realize the welding between plastics.
In the process of ultrasonic welding energy conversion, the larger the amplitude is, the higher the requirements for electronic components, such as the 35K model, the manufacturing cost of using a high-power ultrasonic generator will greatly increase. models to meet the welding needs of the product.
15k 2600W-4000WR models are suitable for large area welding products. The size and length of the single horn mold can reach 900mm (without width), the 20k1800W-2600WR model is suitable for small area welding products such as chargers, the size and length of the single horn mold can reach 500mm (without width), and the 35k model is suitable for Welding miniature products, the size and length of the single horn mould can reach 100mm (without width), except for the multi-horn sharing welding head.
However, for some products with special requirements, such as ultrasonic welding, strict requirements on sealing performance, welding strength, appearance, traditional models are difficult to solve welding problems, ultrasonic mechanical parameters are more stringent, and models are selected according to product characteristics. The loopholes in model parameters will greatly reduce the welding effect. Or affect the welding success rate.