High Frequency welding, or HF welding, is a method of joining plastic materials together using an electromagnetic field coupled with pressure to create a tight seal.
In the HF welding process, electrical energy causes the molecules within the material to move around, generating heat and softening the PVC and PU material so that it begins to fuse together – similarly to the regular lamination process. Once cooled, the HF-welded surfaces become completely fused together, creating an extremely strong join.
This secure bonding creates an airtight environment, providing low permeation of other gases into the bag, and enabling the sample to remain uncontaminated.
At Adtech, we use HF welding to produce PVC and Polyurethane (PU) air sampling and liquid bags for clients on a regular basis, which are vital for protecting critical environments from contamination.
PVC and PU general-purpose sampling bags are quick and easy to produce, extremely durable, and widely used for non-critical testing as a cheaper alternative to more expensive materials, such as FEP, Tedlar® and PVDF.
In producing secure testing bags, we work with PVC and Polyurethane of various thicknesses to produce bags suitable for single or multiple use. All our sample bags a can be supplied with inlet and outlet connectors or ports. So the products that HF welding makes possible are extremely varied.
It is not just bags that we produce with HF welding. Because the process of HF welding enables the plastic to be flexible, we can also create 3D shapes of every possible size and shape which are both reusable and easily cleanable.
This means that we can use HF welding for many innovative use cases – and this is no better exemplified than through our work for a local company that produce custom fit racing seats.
The iNDi-Seat is a well-known brand within the motor sports industry. Their team worked with racing driver Nicolas Hamilton to create a custom-shaped iNDi racing seat. Nicholas was provided with a moulded seat insert that took on his profile, giving him two channels for his legs to sit securely into. This helped him to fit into the base of the shell much more effectively, giving him a higher level of comfort and confidence during his races.
The custom-size bag for the inside of the seat was made from HF weldable materials, formed using HF welding equipment complete with a filling port. This component needed to be capable of withstanding considerable stresses whilst the seat was fitted. Because the driver sat in the seat during the fitting so that the fit could be adjusted to the perfect racing position for his body, putting extra pressure on the inflated materials, it was extremely important that the bond holding everything in place would remain true. With HF Welding, the join proved extremely secure.