Drying chambers are needed for the rapid curing of coatings. Drying chambers are most often used in serial production, where protection against corrosion with paint coatings is applied.
Drying chambers can be divided into two main types: thermoradiation and convection.
Thermoradiation drying chambers
Drying of paints and varnishes in thermoradiative drying chambers is realized by means of radiant heaters which transfer their heat to the articles. Temperature of heaters used in thermo-radiation drying chambers is about 300 - 400 °?. The higher the temperature of the emitter itself (i.e. heater), the more temperature is transferred to the product by radiation. In thermo-radiation drying chambers, as in all others, there are always exhaust shafts above the opening, where the product passes, which draw the air contaminated with solvent vapors out of the chamber. Exhaust ventilation is necessary to maintain the concentration of solvent vapors at an acceptable level.
Thermo-radiation drying chambers look like a long tunnel with open ends, through which the parts, arranged in one row, move. There are heaters on both sides (on both walls of the tunnel). If the part to be dried has a fairly simple shape, or during the drying process rotates, it is heated evenly. For the drying of a product with a complex configuration it is necessary to blow it additionally with hot air for an even curing of the paint material. The air for the supplementary blowing can be taken from the hotter part of the drying chamber and blown into the part with a lower temperature. The air can also be heated in remote heaters. Drying chambers with additional blowing are called thermo-radiation convection drying chambers. In these chambers, the effect of drying by thermal radiation is somewhat reduced, but the inner cavities, which cannot be heated uniformly by radiation alone, are well heated.
Thermo-radiation drying chambers are powered by gas or electricity. The source of thermal radiation can be heaters, incandescent lamps or panel heaters.