Condensed steam (“condensate”) that forms inside a heated corrugator roll may be laying 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 of the 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 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. Kadant Johnson has been developing these technologies specifically for application to corrugator rolls.