Thermoforming, respectively Vacuum Forming, describes a process in which packages such as cups or bowls, technical components such as plastic skins or plastic skin parts and other objects, such as whole bathtubes, are produced. Thermoplastic films or plates of plastic are first heated and then drawn into molds by vacuum or pressed mechanically.
The products remain as long in this mold until the plastic has cooled-down so far that it is not deformed and is stable. The duration of the heating and cooling process can depend on the thickness of the semifinished product.
After removal from the mold, the product is typically removed from its' edge by stamping or milling.
Elstein infrared heaters are used for the heating process in most thermoforming machines. The reason for this is the very good absorption capacity of radiant energy of the heated plastics. Elstein infrared heaters cover the wavelength range of the absorption spectrum of the most used plastic plates and films, this results in an efficient absorption of emitted energy.