The difference between high-frequency welding and hot air welding

High-frequency welding is suitable for large-area welding of PVC membranes and some PTFE composite membranes. It generates heat by exciting the internal molecular vibrations of the membrane material using high-frequency electromagnetic waves, resulting in high efficiency and uniform heating.

For example, in the construction of membrane structures for sports stadiums, high-frequency welding can achieve welding speeds of hundreds of meters per hour, with the seam light transmittance differing from the base material by less than 5%.

Hot air welding uses PFA (fusible polytetrafluoroethylene) welding rods as the hot melt medium. Heating to 420-450℃ using a hot air gun causes the welding rod and membrane surface to melt simultaneously. This process is highly flexible and suitable for repairing curved or irregularly shaped structures, such as partial repairs of the lining of chemical storage tanks. However, the weld strength is approximately 60% of the base material, and its sealing performance needs to be verified through a steam-water circulation test (500 alternating tests without leakage).