Radio frequency (RF) welding is one the most reliable methods of sealing polymer materials for the fabrication of leak-proof, airtight inflatable products. Because of the attributes derived from a welded seam on pliable materials, the potential applications include everything from fluid bags for the medical industry to inflatable bladders for flotation devices.
Radio frequency welding or heat sealing are the preferred methods for the construction of most inflatable products as a result of the strong seal that is created when bonding the materials. They are used primarily in the industrial and medical industries because of the need for a durable air tight, leak-proof port and seam seal that allows for proper inflation and containment.
Inflatable products require more than the airtight seam sealing provided by RF welding and heat sealing services–they also need a means to receive pressurized air to become inflated. The RF welding process is used to integrate ports for inflatable devices by joining a flexible, malleable synthetic fabric or vinyl to the plastic nozzle or opening without compromising either one.
Ports or valves are used to Inflate products. When creating passage for fluid or air through an existing panel, a port or valve is used. Ports, valves or nozzles typically have a weldable flange that makes them ideal for installation at a mid point in a panel. Sometimes it is advantageous or necessary to create air or fluid passage through a seam. While it is difficult to position a port or valve on a seam, welding a tube into a seam is a common practice. With a tube welded into a seam, compression type fit valves and fittings can now be attached to the tubes to support a wide range of inflation requirements.
An inflatable item requires an airtight and leak proof seal. A containment item must also be air, vapor or fluid tight. Typically, an airtight product begins with nonporous material and a method of sealing airtight flexible items together, which is achievable using adhesive, electromagnetic welding (RF) or heat sealing processes.
The term ‘inflatable’ usually refers to flexible products. A very high percentage of flexible and fusible materials are some formulation of plastic resin. Most of those plastics resins are fusible and a relative percentage of them are radio frequency sensitive, allowing a fusible bond with RF and HF welding processes.
When welding at the seam, the best methods involve temporarily melting the surfaces to be joined and immediately compressing those melted surfaces together to create a fused seam or area. This is achieved using tooling dies with radio frequency welding, high frequency welding, or dielectric sealing.