Thickness Divergence
Discrepancies in the cross-machine or machine-direction thickness of a paperboard roll describe the mechanical inconsistency that affects subsequent converting and printing processes. High caliper variation leads to uneven winding tension and creates soft or hard spots within the finished roll. Slitting and rewinding become problematic when these thickness differences persist across the roll diameter.
Converting Impact
Folding carton manufacturers experience registration issues during multi-color offset lithography when the board thickness deviates from the nominal value. Fluctuation in paperboard caliper disrupts the uniform pressure required for crisp ink transfer and precise creasing. When the board passes through folding and gluing sections, uneven thickness causes crooked folds or improper adhesive application.
Consistent thickness ensures the blanks feed reliably into the cartoning machine without jamming the high-speed mechanics.
Equipment Limit
Double-disc refiners and calender stack rolls are the primary mill components that control the final thickness profiles of the finished board. Multi-ply forming sections must maintain uniform slurry distribution to prevent localized wet streaks that later contract during drying. Inadequate moisture control across the web leaves regions of high thickness that cannot be easily flattened by the calender.
Accurate profiling systems remain necessary to keep thickness deviations within the industry standard margin of five percent.
