When welding with ultrasound with cycles, one or more thermoplastic materials are joined by an internal friction in the area of ​​union with each other. It is used everywhere where thermoplastic plastics are used and high quality is required to the joining technique. In relation to other welding procedures, ultrasonic welding is especially suitable when rapid process times are required at high process safety or if no additional materials or diluents are used. Additionally, ultrasonic welding is characterized by the quality, strength and exact reproducibility of welding seams.