Radio Frequency (RF) welding is a process that uses electromagnetic energy to bond materials. Also known as High Frequency (HF) welding, this process creates an oscillating electric field that shifts and moves polar molecules within the materials between a tool and the platen. The movement of these molecules releases energy in heat form. When enough energy is applied, the molecules begin to melt and bond. Pressure is then applied to the bonded area completing the weld.
One of the most important aspects of RF welding is creating a seal that is strong and of consistent quality. The most important factors when creating a seal include:
- Tooling Design
- Weld Thickness
- Machine Control
To ensure you have the best RF welds, use machines that control the power, pressure and time throughout the welding cycle. It is important to note that all RF welds require some adjustment, usually in the pressure level, power level, or in the time needed for the weld and cooling settings.
The History of RF Welding
In addition to HF welding, RF welding can also be referred to as dielectric welding and has been around for over 50 years. RF welding began in Europe as a result of theoretical knowledge of the first radar systems and post-war experience of heating materials. Today there are only a handful of U.S. based manufacturers like JTE leading the way in providing advanced controls for all of its RF machines, specializing in automation and the conversion of existing sewing operations.
Why Use RF Welding?
The appeal of RF welding lies in the complete weld that it provides. RF welding also yields robust hermetic seals that are very airtight and pass peel, leak, and optical tests. RF welding can also be performed on most common materials, such as:
RF welding and heat sealing are often used interchangeably, with some RF machine manufacturers going so far as to refer to some of their machines as “heat sealers.” In reality, this is incorrect, as heat sealing is the process of sealing one thermoplastic to another similar thermoplastic using a combination of external heat, and pressure. Although both involve heating up molecules within materials, RF welding doesn’t require an external heat source. Thus allowing the material to be more evenly heated and allowing better consistency in addition to being able to weld thicker materials together.
If you would like to learn more about the types of products that can be made using RF Welders, click on the link below to download our eBook The Top 20 Products Made With RF Welders.