Longitudinal ultrasonic welding process
The process is based on a pulsating, very fast, change in length of the sonotrode in the range of 15 to 60 µm. The ultrasonic energy is thus introduced into the component at a 90° angle to the sonotrode contact surface. The energy then focuses in the optimally designed welding plane and causes the thermoplastic material to melt. After the melt cools, a solid joint is then formed.
Most commonly used process in the field of ultrasonic welding of thermoplastics.
Torsional ultrasonic welding process
Also in this process, the sonotrode is placed on the component at a 90° angle. The process is based on a pulsating, very fast rotational movement in the range of 15 to 60 µm. As a result, the parts to be joined make a relative movement to each other. In the correspondingly designed welding plane, the material is made to melt. After the melt has cooled, a solid joint is then formed.
The advantage of this technique is the lower stress on the parts due to the rotational energy input. The process is therefore suitable for sensitive joining parts, films and membranes.