IMPULSE DRYER ROLL WITH SHELL OF HIGH THERMAL DIFFUSIVITY WITH HIGH TEMPERATURE DISTRIBUTION SHELL

摘要

In the paper machine, the roll 22 is composed of two parts. A metal base shell 38 made of a conventional spun-cast steel alloy, and a thin outer shell 40 made of a high thermal diffusivity material. This thin outer shell 40 is one-tenth of a inch thick and is in intimate contact with the surface of the alloy steel base shell 38. Typical materials of high thermal diffusivity for use in the outer shell are copper and aluminum. The roll 22 may be molded by sputtering a copper layer to a thickness of 2/10 of about 1 inch on the surface of the alloy steel base shell 38. The rolls 22 are used where the heat transfer to the paper web is improved, such as impulse paper dryers, or calenders.;[Selectivity] First diagram