Infrared welding is a process in which plastic workpieces are heated by a non-contact heating method, and bonded together after being pressed and cooled.

The infrared welding process includes two stages: the heating stage and the actual welding.

The more suitable the wavelength radiated by the infrared lamp tube is to the absorption capacity of the polymer material, the higher the efficiency.

Using infrared technology for welding, infrared radiation with a spectrum of short wave (0.78-1.4um) and fast medium wave (1.4-2.0um) can be used. This depends on the absorption wavelength range of the polymer material. Short-wave heating can achieve more penetration and inner layer heating, while medium-wave heating is more concentrated on the surface.

The closer the radiation source is to the point to be heated, the better the focus of the light and the faster the material will heat up.

Since the distance between the heated material and the lamp tube has a great influence on the melting result, a lot of adjustments must be made (so most infrared welding machines are equipped with servo motors). The distance depends on the geometry of the part, the material and its absorption characteristics, and the wavelength of the heating lamp.

In addition, in order to avoid infrared radiation to those areas that do not require heating, you can change the path of infrared radiation by adjusting the position of the lamp coating and using the so-called "barrier plate" to ensure that the infrared beam is only reflected on the welding surface. Deformation or damage of these visible areas.