In the production of face masks made from thermoplastic materials, processing with ultrasound scores highly in terms of efficiency, flexibility, and quality. Excellent system reliability, perfectly hygienic tools, and long-lasting material bonds are the prerequisite for producing high-grade products. Ultrasonics provides the cleanest, fastest, and most efficient method for assembling non-woven materials.
Ultrasonic welding is a process used to join two plastic parts together to form a strong, finished assembly. The process relies on high-frequency (ultrasonic) vibrations being generated and applied to the parts via a horn. Welding occurs as the vibrations are absorbed in the interface between the two parts, generating friction and causing the plastic to melt. The ultrasonic vibrations are generated by a series of components, including the power supply, converter, booster, and horn, ultimately delivering the mechanical vibration to the parts.
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How does the ultrasonic welding work
The ultrasound converter converts the electrical signal from the generator into mechanical vibrations. They, in turn, are directed to the workpiece to be welded via the booster and the sonotrode under specific pressure.
The mechanical vibrations generate frictional heat at the workpiece’s defined joints, which causes the material to melt and bonds the parts together.
During a brief cooling phase, a clamping force is applied to fuse the plasticized material. The pieces welded together with ultrasonic energy are immediately available for further processing.
Depending on the application, the sonotrodes can weld vertically, horizontally, and continuously.
Advantages of ultrasonic welding
- Does not need an external heat source: Ultrasonic welding’s primary advantage is that it doesn’t need an external heat source. The heat is self-generated between the materials.
- Fast: Since vibrations’ frequency is very high, ultrasonic welding is one of the quickest welding methods available in the industry.
- Possibility of automation: Ultrasonic welding being uncomplicated in many ways, is easy to automate. The ultrasonic machine comes with sensors that constantly monitor the temperatures.
- Clean and robust joint: The contact surfaces melt/fuse upon welding, and it produces a very clean and robust joint.
Ultrasonic welding has many advantages when compared to traditional welding technologies. Many industries use ultrasonic welding due to these specific combinations of merits.
Ultrasonic face mask welding
Which kinds of non-woven fabrics can be welded
Ultrasonic sewing is the best way to assemble nonwoven fabrics for single-use products. With the rapid development of the economy, ultrasonic welding technology is more and more widely used, such as disposable facemasks, disposable protective clothing, surgical gown(operating coat ), diaper, non-woven pockets, gloves, etc.
Ultrasonic welding tips
Ultrasonic welding is very effective at sealing or welding plastics. However, you cannot weld all types of plastics. Nike metals, plastics also have different styles. And it is essential to ensure that the plastics to be welded are chemically compatible. If you try soldering polyethylene and polypropylene, they may melt together, but there will be no chemical bond. A chemical bond is essential for creating strong weld joints. Another factor to keep in mind while welding any material through ultrasonic welding is maintaining a uniform contact area.