Ultrasonic welding is an industrial technique whereby high-frequency ultrasonic acoustic vibrations are locally applied to workpieces being held together under pressure to create a solid-state weld. It is commonly used for plastics, and especially for joining dissimilar materials. In ultrasonic welding, there are no connective bolts, nails, soldering materials, or adhesives necessary to bind the materials together 

All ultrasonic welding systems are composed of the same basic elements:

  • A machine to put the 2 parts to be assembled under pressure
  • A nest or anvil where the parts are placed and allowing the high frequency vibration to be directed to the interfaces
  • An ultrasonic stack composed of a converter or piezoelectric transducer, an optional booster and a sonotrode (US: Horn). All three elements of the stack are specifically tuned to resonate at the same exact ultrasonic frequency (Typically 20, 30, 35 or 40 kHz)
    • Converter: Converts the electrical signal into a mechanical vibration
    • Booster: Modifies the amplitude of the vibration. It is also used in standard systems to clamp the stack in the press.
    • Sonotrode: Applies the mechanical vibration to the parts to be welded.
  • An electronic ultrasonic generator (US: Power supply) delivering a high power AC signal with frequency matching the resonance frequency of the stack.
  • A controller controlling the movement of the press and the delivery of the ultrasonic energy.

Ultra Sonic Welding Diagram

Craftech Corporation specializes in value added services such as Ultrasonic Welding. The Ultrasonic Welding process enables the joining of two or more injection molded plastic components using sonic vibrations which cause friction between the two. The friction causes heat which melts the plastic pieces together. When the process is engineered properly a very clean and potentially hermetic seal can be achieved with this process. To learn more about the process, joint designs and how it works please contact us through this link Sonic Welding.