All of SealWerks’ seam sealing services render an airtight or fluid proof seam through the fusing of flexible and pliable material types. The process you’ll need depends on a number of factors: the material type used, the size and shape of the product, the volume of work needed, the required appearance and strength of the seam, and the custom applications needed for product functionality.
Factors That Determine The Best Sealing Process
Several factors are considered in selecting a process that best suits the material used and the products utility, including:
- The required internal pressure for air containment, gas containment or fluid containment
- The type of tubes, ports or fixtures that need to be attached to the welded unit
- The width of the weld seam or seam seal
Below are basic descriptions of the processes to help you determine which may work best for your application. Since we offer all of these textile sealing services at SealWerks, we can answer your questions and objectively determine which process will work best for your project.
When To Use Radio Frequency (High Frequency) Welding / Dielectric Sealing
Radio frequency welding, high frequency welding and dielectric sealing use electromagnetic energy at a high frequency to fuse polar molecular materials together. These processes are referred as different terminology but they produce the same welding attributes. The RF welding process is used for small to moderate-sized products that require the melding of the same, or different materials types. Since most people refer to this welding process most often as radio frequency welding, we will use RFW to describe the attributes of all three of these welding terms.
Advantages
An advantage of the RF welding process is that it offers better control when using very thin materials, and constructions with very close dimensional tolerances. RFW is fast and heats the material quickly, is safer to handle, and keeps its shape immediately after sealing. A radio frequency welded seam provides the best quality seal in appearance and bond performance.
Applications
Radio frequency welding/high frequency welding/dielectric sealing* is best utilized for:
- Small to moderate sized products
- Products requiring tube or port welds
- Large quantity production (if size and configurations are within parameters)
- For flexible products which require narrow or tightly configured seams
- When tight dimensional tolerances are required
- When very thin materials are welded or sealed together
*High frequency welding and dielectric sealing are the same manufacturing process as radio frequency welding.
Hot Air Welding Is Used For Over Sized Products
Hot air welding uses a nozzle to channel heated air between two layers of material. A heat seal is used when materials need to be configured into closed chamber/tube type constructions, complex (multiple plane) configurations, or when welding thick material. This process is fast and allows for a ‘continuous’ welding of materials, or to form large curved constructions. Because of these benefits, hot air welding is ideal for sealing seams on large, oversize products.
Hot Wedge Welding Is Used For Close Tolerances
Hot wedge sealing is used when the optimum material for your project is not radio frequency weldable. Hot wedge sealing provides a much better fabrication system for close tolerances and accurately positioned voids in the weld. It also offers better control when using very thin materials and constructions with very close dimensional tolerances. Hot wedge sealing utilizes the same basic equipment as hot air welding, embraces the same parameters, but allows for more process control of thinner materials and tight curves.
Note: Hot air welding and hot wedge welding will bond a much wider range of materials than radio frequency welding.
Solvent Bonding is Chemical Adhesive Binding For Specific Applications
Solvent bonding or solvent sealing is a process in which the surfaces of the materials to be joined are treated with a solvent. The solvent temporarily softens the material and the bond is made by chemical reaction. As the solvent evaporates, the two surfaces render a tight, permanent bond. It is commonly used for securing fill and vent tubes, and to close chamber type constructions.
