| Infrared is broken down into three sub-groups, namely short
(near), medium, or long (far) wavelengths. Short
wavelength infrared ranges from 0.76 - 2 microns or 7000°F
- 2150°F.
Medium wavelength infrared ranges from 2-4 microns or 2150°F
- 845°F.
Long wavelength ranges from 4 - 1000 microns or 845°F
- below freezing.
The effective infrared heating range is from 1.17 microns
(4000°F) through 5.4 microns (500°F). Below 500°F
the heat transfer rate is very low and infrared heating becomes
less effective for process applications. Temperatures below
500°F are more commonly convection heating applications.
Wavelength and
temperature are inversely proportional.
As the wavelength goes down, the temperature goes up.
It should be noted that the temperatures discussed above
relate to the heater face temperature, not the process temperature.
The heater face temperature is typically 2-4 times higher
than the required process temperature. |
