Roll-grind quality is a key factor in maintaining consistent containerboard production performance. Measurements from a recent evaluation indicate that tight-tolerance grinding can improve strength characteristics in the board, contributing to a more uniform product across the machine.

A Southern containerboard mill contacted Precision Roll Grinders to improve variability in strength performance through tight-tolerance calender roll grind. Working with specialists from Precision Roll Grinders, a single roll was serviced, returned to production, and monitored over several weeks to assess production improvements. The containerboard’s caliper variation was monitored, showing a reduction of over 70% in 2-sigma CD caliper variation in the collected data. With improved caliper variation, calender roll loading can be reduced to improving the strength quality of the sheet. The data confirmed measurable improvements in Mullens strength characteristics, highlighting the impact that tight-tolerance grinds can have on strength in the paper-making process.

Mullens strength values showed greater stability, with reduced week-to-week variation and less fluctuation in strength retention with an increase in Mullens strength overall. Steadier performance points to a more predictable sheet structure when passing through the calender nips. This observed improvement illustrates that tight-tolerance grinding can enhance strength consistency and product stability within the calender section, supporting mills in producing a stronger, more reliable, and more profitable containerboard product.

Contact your local Precision Roll Grinders account manager for more information.