Profiled for Success
Last week we explored the differences in heat profile between conventional cartridges and
Watt-Flex® cartridge heaters. The uneven profile of the conventional heater is caused by
two or more coils, wired in parallel to the terminal posts. But uneven heating is magnified
if one of the two or three coils opens and fails to heat … a half or a third of the heater fails
to heat. In a sealing bar or heat seal platen application, for example, the bar or the platen
will fail to seal properly in the cold area, presenting massive quality problems for the product.
If the thermocouple is close to one of the areas of the heater that is still working, the
machine operator will have no indication that there is a problem until it is recognized that
a volume of scrap has been produced. The Watt-Flex® cartridge heater, on the other
hand, has one continuous coil, regardless of its length. Therefore, if serves as a giant
resistor, either working or not. There is certainly no doubt that it is fully operational and
full heater profile heat is being provided.