Determination of the Temperature Rise and Wrinkling Behavior of Webs Transiting Heated Rollers

Abstract

Many materials are manufactured and processed as webs. Examples of webs include: paper, plastic films, textiles, and metal foils. Due to the thin nature of webs, geometric instabilities can arise during web handling processes. These instabilities can cause the web to deform out of plane. When these deformations occur in the span between rollers, they are referred to as troughs. A wrinkle is any out of plane deformation that transits a roller along with the web. Wrinkles can cause creasing and damage to the web material. There are many observed and documented conditions that cause the formation of troughs and wrinkles. One condition which has been widely observed not yet widely investigated is wrinkling of webs transiting rollers which are either heated or cooled. There are many processes which require the web to be either heated or cooled so understanding the behavior of the web as it undergoes temperature changes associated with these processes is advantageous to manufacturers. This research focuses on polyester film. The goal is to better understand the behavior of webs which transit rollers of elevated temperature and, also, determine the conditions under which wrinkling can occur and see if these conditions can be predicted.