Difference factor one: Firstly, plastic welding works differently to metal welding machines.
As a rule the welding head vibrates in a direction perpendicular to the welding position in ultrasonic plastic welding, whereas in ultrasonic metal welding the welding head vibrates in a direction parallel to the welding position. Of course in some special cases plastic welding can also be done in a parallel direction, for example with thinner plastic parts.
Different factors two: Secondly, due to the application of ultrasonic welding metal, ultrasonic welding technology has put forward higher requirements, compared to ordinary plastic welding, power capacity, power density, stability and automation control and other aspects of the requirements, are not the same level.
Now the domestic ultrasonic plastic welding with generators are basically using self-excited circuit.
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