SealWerks specializes in custom RF welding services to create durable and airtight seals for shaped inflatable containment products. Our radio frequency welding services ensure a hermetic bond, essential for health and safety in containment devices. Whether you need to contain liquids, gases, or gels, our custom RF sealing services offer the ideal flexible solution.
Our team of expert engineers is ready to help you determine if RF welding is the perfect fit for your project. Contact us to discover how our custom RF welded products can meet your specific needs with precision and reliability.
RF welding, or high-frequency welding, is a process for joining plastics by applying a high‑frequency electromagnetic field between electrodes to heat the material from within. The oscillating field makes dipolar molecules in compatible thermoplastics vibrate and generate heat; under clamp pressure, the molten layers fuse and then solidify into strong, uniform, often airtight or watertight seams. It works on polar plastics such as PVC and polyurethane (not on non‑polar polymers like polyethylene) and is widely used for items like medical bags, inflatables, and protective covers.
Dielectric Welding, also known as RF Sealing or heat sealing, is a high-frequency process that joins thermoplastics by placing them between shaped electrodes and applying a radio-frequency electromagnetic field to heat the material from within. Pressure then fuses the layers into uniform seams. The process is more commonly referred to as radio frequency (RF) welding. Unlike conventional hot‑bar heat sealing, the heat is generated inside polar plastics (commonly PVC and polyurethane) as their dipolar molecules oscillate in the field, producing strong, repeatable seals for flexible containment products and custom soft goods.
Combining high-frequency welding with our ISO Certified Manufacturing process, you get consistent results whether you need 100 pieces or 100,000.
Medical equipment like bellows and rebreather system bladders benefit from its clean process that does not employ any adhesives or solvents.
Choose RF welding when you need:
Here are some examples of products constructed using Radio Frequency technology:
Radio Frequency welding creates strong seams using no additional bonding agents. It can be used to fuse a range of flexible materials, including:
Industries that benefit from the Radio Frequency bonding process:
RF welding and RF sealing work best with polar thermoplastics. Their molecules have strong dipole moments and high dielectric loss factors that convert RF energy into heat at the seam. Top performers include PVC, polyurethane (PU), and thermoplastic polyurethane (TPU); their polarity (and, for PVC, common plasticizers) enables fast, uniform heating for clean, hermetic bonds. TPU‑coated nylon or polyester fabrics weld through the TPU layer to create reinforced airtight seams. Certain copolyesters like PETG and some PET grades, as well as EVA films with sufficient vinyl acetate content, also respond well to RF energy. Select TPE films with polar segments can be RF sealed effectively as well.
In contrast, low‑polarity materials such as polyolefins (e.g., polyethylene and polypropylene) absorb RF energy poorly and typically require RF‑reactive coatings, tie layers, or compatible laminates to seal—otherwise they are better suited to heat sealing methods. Beyond base resin, formulation and design choices impact results: plasticizer level in PVC, moisture content, pigments and fillers, fabric weave, and film thickness all influence weld speed and seam strength. For airtight inflatables, containment devices, and medical components, choosing the right grade and thickness of PVC, PU/TPU, PETG, or EVA—and validating frequency, power, pressure, and dwell ensures repeatable, high‑strength RF welded seams.
The best sealing process for any application is determined by the materials, product size, and configuration. When you need to use materials or components that are not RF sensitive, heat sealing services or solvent bonding can be alternative options.
Thermal impulse welding or heat sealing bonds a wider range of plastic films and plastic-coated fabrics than RF and HF welding. The results and applications are very similar.
SealWerks combines engineering know‑how with dependable project management to deliver custom RF welding services and custom RF sealing services that meet your performance, budget, and timeline goals. From material selection and DFM to tooling, sampling, and production, our radio frequency welding services (also called dielectric welding services) are built around clean manufacturing, repeatable seams, and responsive support for applications like airtight inflatables, fluid containment, and protective soft goods.