During the production of corrugated board, flute crushing is a common issue. Once the flutes are flattened, the board’s compression strength is significantly reduced, directly affecting the box’s stacking and load-bearing performance. The causes of flute crushing vary, and the main issues and solutions are summarized below.
Main Causes & Solutions
1.Corrugating rolls are not parallel (flute tilt)
Solution: Adjust the corrugating rolls to ensure full parallel alignment.
2.Low flute height at the start or worn corrugating rolls
Solution: Replace the corrugating rolls.
3.Flutes are crushed after forming
Solution: Inspect and correct all nip points or contact points that may crush the flutes.
4.Excessive tension on the medium paper roll
Solution: Reduce the brake force on the paper stand; check the preconditioner position; dry, repair, or replace the preconditioner’s drive motor.
5.Too much steam from the spray system, causing over-moistening
Solution: Reduce the amount of steam applied to the medium.
6.Glue unit crushing the flutes at any nip point
Solution: Reduce glue application while maintaining good bonding and preventing warping; if medium moisture is too high, reduce steam, shut off spray systems, or replace the medium paper roll.
7.Uneven tension of the double-facer belt (diagonal flutes)
Solution: Keep the conveyor belt tension and running speed consistent.
8.Low compression strength of the medium paper
Solution: Replace the medium paper roll and consult with the paper supplier.
