Frequently Asked Questions
1. What is High Frequency Welding?
2. What material can be welded by High Frequency?
3. What is Ultrasonic Welding?
4. Is a mold/die required for HF Welding?
5. What are the advantages of HF over other straight heat technologies?
6. Why arcing occurs in HF Welding?
7. Why insulation/barrier/buffer material should be used in HF Welding?
8. What insulation material should be chosen for different applications?
9. What plastics can be welded to give best results in ultrasonic welding?
What is High Frequency Welding?
High Frequency Welding is the process of fusing materials together by applying high frequency energy to the area to be joined.The energy produces localized heating of the materials, causing them to soften and melt, thus allowing their molecules to intermingle.After a period of cooling, the materials become joined together at the point of the weld.The resulting weld can be as strong as the original workpiece materials.
What material can be welded by High Frequency?
Suitability of a plastic for HF welding is determined by its molecular construction.Material most commonly used is PVC, PU and other PVC compounds
What is Ultrasonic Welding?
Ultrasonic Welding delivers mechanical energy which when transferred to a thermoplastic material under pressure fuses the material.Most of the rigid thermoplastic material can be ultrasonically welded after the workpiece is injection-molded.
Is a mold/die required for HF Welding?
Yes, a mold/die is required.To achieve the weld, the PVC films are placed between the brass/copper die (with raised areas representing the required weld pattern) and the lower electrode (the aluminium worktable) of the HF machine.The press head of the machine comes down and presses on the films.The HF is generated and channeled through the material in the pattern areas only, fusing the materials together at those points.
What are the advantages of HF over other straight heat technologies?
Unlike with a straight heat weld, the material is only heated while HF is being generated.HF-generated heat does not radiate off the die like that on a straight heat machine.This prevents heat-degradation of the material.Once the HF is turned off, the material stops being heated, but remains under pressure to allow it to be cooled under compression.Better welding result and more control over the melt can be achieved.
Why arcing occurs in HF Welding?
An electrical " flash " will occur if the welding machine's electrodes (the upper mold/die & the lower aluminium worktable) come too close together or touch each other. Arcing can damage both the generator and the tooling, therefore most of our standard machines are equipped with the arc suppressing device/circuits to cut