Ultrasonic Welding Process

Ultrasonic welding is a widely used technique in plastic manufacturing for joining two or more plastic parts together. This process uses high-frequency ultrasonic acoustic vibrations to create a solid-state weld. It is known for its speed, efficiency, and ability to produce strong, reliable bonds without the need for adhesives or fasteners.

OUR PROCESS

1

Preparation

• Design & Material Selection: The parts to be welded must be designed with ultrasonic welding in mind, including features like energy directors to facilitate efficient welding. Thermoplastic materials are commonly used due to their ability to soften and re-harden.
• Fixture Setup: The parts are placed in a fixture that holds them in precise alignment during the welding process.

2

Welding

• Horn & Anvil Positioning: The ultrasonic horn (sonotrode) and anvil are positioned on either side of the parts to be welded. The horn delivers ultrasonic vibrations while the anvil provides support.
• Application of Pressure & Vibrations: The ultrasonic welding machine applies pressure and delivers high-frequency vibrations (typically in the range of 15 kHz to 20 kHz) through the horn to the interface of the parts.
• Heat Generation & Melting: The ultrasonic vibrations create frictional heat at the contact points, causing the plastic material to melt and fuse together.
• Cooling & Solidification: Once the vibrations stop, the pressure is maintained for a short time to allow the melted plastic to cool and solidify, forming a strong bond.

3

Post-Welding

• Inspection: The welded parts are inspected for quality and strength, ensuring that the bond meets the required specifications.
• Trimming & Finishing: Any excess material or flash resulting from the welding process may be trimmed or finished as needed.