Cross Machine Caliper Profile Control on High Speed Coated Packaging Lines
Cross-machine caliper control demands real-time induction calender profiling to maintain stiffness and prevent high-speed converting line jams.
Blade Coating Profiling
Application Control
A process optimization method determines the distribution and thickness of liquid formulation applied to a paperboard surface by a flexible steel blade. Through blade coating profiling, operators measure the pressure profiles and blade wear patterns to ensure a uniform layer of coating across the entire width of the web. This technique limits defects such as streaks or uneven absorption, which can ruin subsequent high speed printing operations.
The evaluation of blade angles and beam pressure allows for precise adjustments during high speed production runs, ensuring that coat weight remains stable even as the machine speed fluctuates.
Wear Pattern
Continuous scraping against the fast moving paper web causes localized wear along the metallic edge of the coater blade. As the blade wears, the applied volume of the coating slurry shifts, leading to dry coat weight variations in the cross direction. Profiling detects these physical changes before they result in quality rejections.
Measuring the blade profile after use reveals the force distribution exerted across the paperboard surface during the run.
Mechanical Adjustment
Dynamic adjustments of the pneumatic actuators across the blade holder alter the local tip pressure to maintain the target coat weight. These corrections offset the natural variation in base sheet roughness across the web. Proper profiling prevents excessive blade pressure, extending the service life of both the blade and the backing roll.