Condensed steam (condensate) that forms inside a heated corrugator roll may be lying on the bottom of the roll (puddling), tumbling around inside the roll (cascading), or spinning with the shell (rimming).  The condensate behavior inside the roll significantly affects the rate and uniformity of heat transfer to the outside of the roll. Many heat transfer problems encountered by corrugator rolls relate to the condensate behavior which in turn depends on the rotational speed of the rolls.  This is similar to the way condensate behaves inside steam-heated paper dryers, except the corrugator roll diameters are much smaller.

Technologies related to steam and condensate systems similar to those used in paper dryers can be used to provide uniform, stable, and high heat transfer rates in corrugating rolls, even at high corrugating machine speeds.  Modern steam and condensate systems control differential steam pressure and blow-through across each roll to achieve the highest possible heat transfer and temperature uniformity, with higher efficiency and less maintenance than any conventional steam trap system. This system addresses the heat transfer problems that Kadant Johnson has found to be plaguing modern corrugators.