High Frequency Welding, otherwise known as dielectric or radio frequency welding, is a process used to bind plastics. High frequency welding falls under several other umbrella terms, such as heat sealing and plastic welding. The technology behind high frequency welding has been around for quite a while, from the 1940's actually, so it is a proven and reliable technique used in product manufacturing. By applying radio frequency energy to certain receptive materials, it allows them to be bonded, and many times the weld can be just as strong as one uniform piece of material. This makes it a popular choice where leak proof seals are needed. High frequency welding relies on manipulating specific properties of a material. By utilizing a high frequency (13-100 MHz) electromagnetic field, HF welding generates the heat necessary for a heat seal bond. The area to be welded is pressed between two metal bars which act as both the conduits for the energy field and the pressure applicators for heating and cooling. When the frequency is applied, it causes the molecules of polar thermoplastics, such as PVC, to spin. The molecules spin fast enough to generate a strong heat which makes the material malleable and capable of being altered to the shape of the die. The pressure keeps the surfaces tightly together so that when the high frequency is turned off and it cools, it makes a leak proof weld. An RF weld (yet another name for high frequency welding) is very fast and quite consistent in producing a strong leak proof seal. This makes it quite popular for a variety of industries needing a proper heat seal when using the right materials for bonding. Many of the common materials that can have an RF Welder are plastics that contain chemical dipoles. Materials such as PVC, polyamides and acetates, are all receptive to the electromagnetic waves used for high frequency welding. PVC and polyurethanes are some of the most common materials for this sort of heat sealing.
