PP.PA.ABS Plastic Packing Tape Welder

In ultrasonic welding, the determination of the optimal pressure is essential for good welding. The welding pressure provides the static force required for the coupling of the welding horn to the part in order for vibration to pass into the part. During the packing phase of the welding cycle, when the molten material at the joint solidifies, the same static load ensures that the parts are joined together. If the pressure is too low, it will cause poor or insufficient melt flow with poor energy transfer, resulting in a long welding cycle. Increasing the welding pressure reduces the welding time required for the same displacement. If the pressure is too high, it will cause molecular orientation along the flow direction and reduce the strength of the weld, resulting in part indentation. In extreme cases, if the pressure is too high relative to the amplitude at the end of the sonotrode, it may overload and stop the sonote. In ultrasonic welding, high amplitude requires low pressure, and low amplitude requires high pressure. As the amplitude increases, the acceptable pressure range narrows. Therefore, the most important thing for high amplitudes is to find the optimal pressure。

Most Plastic Ultrasonic Welding Machine is carried out under constant pressure or constant force. For some devices, the force can be changed during the cycle, i.e. the force classification (Nreeprofi-ling), the welding force is reduced during the application of ultrasonic energy to the part. The decreasing weld pressure or force late in the welding cycle reduces the amount of material extruded from the joint, prolongs the intermolecular diffusion time, reduces the molecular orientation and increases the strength of the weld. For polyamide-like materials with lower melt viscosities, this can greatly improve weld strength. Different materials determine the amount of static pressure required at the time of welding, and choosing a pressure value of the right size has a very important impact on the welding result. The unit of pressure of Ultrasonic Welding Machine is generally used: kg/cm2 (KG/CM2) or MPa MPa.

Therefore, it is necessary to select a suitable pressure value, so that the contact area is in the maximum range, the connection area is the largest, and the strength of the final joint is maximized. As with the choice of amplitude, within the appropriate range, the greater the value of the pressure, the shorter the welding time required during welding, and at the same time, the strength of the solder joint can be guaranteed, so it is recommended that you choose a higher pressure value in actual operation.

For general small products, we adjust the pressure to 0.3---0.4MPa, and for some products with harder materials and thicker wall thickness, the general pressure is adjusted to 0.5--0.6MPa. The specific values are based on the results of the on-site commissioning, and there is no strict and uniform standard. Because the effect of 20K Ultrasonic Plastic Welder is not only related to the welding pressure, but also has a very close relationship with the ultrasonic amplitude, the frequency of the ultrasonic wave, the pressure of the ultrasonic pre-trigger, the material of the product, and the welding requirements.