Integrating Process and Automation for Stability and Agility in Boardmaking, 2002 Technology Summit Proceedings

Dave Lang

The ideal board production line should be both stable and agile. Stability allows production of consistently high-quality board. Agility is required to start up, recover from breaks, and switch production from one grade to another with a minimum of lost time and material. As speeds increase, the inadequacies of traditional stock prep and short circulation process designs are becoming more and more evident in both of these areas.

This paper examines the control problems encountered in the traditional stock blending and short circulation sub-processes feeding the machine. Some problems can be overcome using new instrumentation and by careful design and tuning of the control systems. Others require re-thinking the fundamental design of the process. One proposed new process design will be discussed. As well as improving the stability of the wet end, it will permit grade changes to be made much more quickly than is possible with today's production lines.