Cardboard thickness loss in production
The loss of thickness of corrugated board will always result in poor quality test results, especially the impact on flat compressive strength (FCT) and bending strength (Sxy), which should be avoided in production.
There are two main reasons for this defect: one is that the forming of corrugations is not good in a single-sided machine; the other is that during certain manufacturing operations, the corrugations are collapsed due to overpressure, and today, due to the use of non-guided In the single-sheet paper machine, corrugation is rarely formed. Since the corrugating medium is formed by the cross section of the lower corrugating roller, the correct shape of the corrugated shape can be ensured.
It is also common for corrugated corrugated cardboard to be collapsed on the production line, which is mainly due to the following reasons.
(1) The pressure of the bevel conveyor on single-sided corrugated paper.
(2) The pressure of the glue roller on the cementing machine.
(3) The pressure of the weight roller located above the hot plate on the double-sided machine can be greatly reduced by adopting an air pressure cover. These weight rollers can also collapse the edges of the paper, which is detrimental to the quality of the accumulation.
(4) The pressure on the feed and discharge devices on the knife can be reduced by using a vacuum conveyor belt.
(to be continued)