Based on a long tradition of ultrasonic processing KLN Ultraschall AG also today develops and builds edge-welding machines for textile back injection molded parts. Here in very complex fixtures the textile overlap is put around the part and fixed by means of special sliding technology. This is a highly complex task and requires sound experience in construction and optimisation of the assembly. Here the important know-how is the tool design and not the machine technology. After “edge folding” the stretched textile overlap is permanently bonded with the plastic by means of ultrasonic technology or permanently heated elements on the back of the plastic part.