Cross Direction Control: A Case Study, 1994 Coating Conference Proceedings

Karl Christianson, Kevin DePoy

Over the last few years, coated paper producers have taken a serious interest in automatic, cross-direction coat weight control. These producers are looking for value-added process improvements to directly impact their bottom line. Besides supercalendering, the coating process is one of the last opportunities to significantly improve product quality through automation and control. As a result, mills are looking to coating station, either “on” – or “off-machine”, to create or maintain a competitive position through increased sheet quality and yield.

This paper studies one such mill, Repap Papers in Kimberly, Wisconsin, and documents the value-added quality improvements obtained. This study includes details on the improvements realized in machine-direction (MD) and cross-direction (CD) coat weight variability, reduction achieved in blade-tip wear, and the impact on overall quality and runnability. In addition, some of the economic benefits or savings attributable to CD coater automation are calculated and discussed.