Plastic Ultrasonic Welding Process

April 27, 2023
Latest company news about Plastic Ultrasonic Welding Process

In modern industry, we can see ultrasonic welding machines everywhere. For example: product packaging, cutting, riveting, embossing, punching and other industries all need ultrasonic welding machines, so there are all kinds of ultrasonic welding with various functions. The application fields are different, the usage methods and equipment requirements very different.

latest company news about Plastic Ultrasonic Welding Process  0


The thermal resistance must reach the melting point of the workpiece
After the ultrasonic transducer converts electrical energy into machinery, it is transmitted through the material molecules of the workpiece. The acoustic resistance of ultrasonic sound waves in solids is much smaller than that in air. When the sound waves pass through the joints of the workpieces, the acoustic resistance in the gaps is large. , the heat energy generated is quite large. The temperature first reaches the melting point of the workpiece, and a certain pressure is added to weld the seam. The other parts of the workpiece will not be welded due to their small thermal resistance and low temperature.


Two kinds of workpieces must be weldable
Some of different materials can be welded better, some can basically melt, and some can't melt. The melting point of the same material is the same, and it can be welded in principle, but when the melting point of the workpiece to be welded is greater than 350°C, it is no longer suitable for ultrasonic welding. Because the ultrasonic is to melt the workpiece molecules in an instant, the judgment is based on the fact that within 3 seconds, if it cannot be welded well, other welding processes should be selected. Such as hot plate welding, etc. - Generally speaking, ABS material is the easiest to weld, and nylon or PP material is the most difficult to weld.


The seam area has certain requirements
When the instantaneous energy is generated, the larger the seam area, the more serious the energy dispersion, the worse the welding effect, or even impossible to weld. In addition, ultrasonic waves are transmitted longitudinally, and the energy loss is proportional to the distance. Long-distance welding should be controlled within 6 cm. The welding line should be controlled between 30--80 wires, and the arm thickness of the workpiece should not be less than 2 mm, otherwise it will not be well welded, especially for products that require airtightness.


The output power of Hebo welding machine should be balanced
The output power of the ultrasonic welding machine is determined by the diameter, thickness, material, and design process of the piezoelectric ceramic sheet. Once the ultrasonic transducer is finalized, the maximum power will also be finalized. Measuring the output energy is a complex process. , it is not that the larger the ultrasonic transducer is, the more ultrasonic power tubes are used in the circuit, the greater the output energy, it requires a rather complicated amplitude measuring instrument to accurately measure its amplitude,