Infra red ovens
Basically, infra red heat energy is emitted by a hot body and transferred in straight lines until it makes contact with another body when the heat is absorbed by the latter causing it to rise in temperature.
Advantage of radiant heating
It produces a rapid rise in object temperature. As the temperature of the heating source is increased, so the proportion of heat transferred by radiation as opposed to convection increases appreciably. The amount of heat energy radiated from any source depends upon its area, its temperature and its emissivity.
Medium temperature radiation offers the most effective source of radiant heat for curing thermosetting powder. Usually the emitter panels are gas-fired giving a panel surface temperature of 850-950oC, or alternatively sheathed electric panels of a surface temperature of 750-850oC. The workpiece is maintained at about 30cm from the emitter panel surface with a minimum distance of 15cm.
The color of the powder is an important consideration light colors can reflect (depending on powder composition) proportionately more infra-red radiation and do not heat up as quickly as the darker colors. This means that each and every powder must be evaluated to determine the optimum curing conditions.
As radiant heat tracks in straight lines, coated articles of intricate design, or having sections shielded from the radiation source cannot be processed using this method. Ideally infra-red radiation is used for simple workpieces such as relatively flat surfaces