Reasons for occurrence
1、The difference in the shrinkage rate of the fiber organization of the original paper is large;
2、If the basis weight of the facial paper or lining paper is low and the fiber organization of the original paper is too soft, the rigidity after molding will be correspondingly poor;
3、When the coating amount of adhesive is too much or uneven, it also has glue on the two sides of the corrugated top edge, and when it is bonded and dried with the surface paper or lining paper, it causes a certain torque to the surface paper or lining paper due to the shrinkage effect;
4、The viscosity of the adhesive is low, and it does not adhere well to the fibers of the liner or surface paper to form a strong whole;
5、The corrugated roller, pressure roller clearance of single-sided machine or double-sided machine is improper, unbalanced;
6、When the top of the corrugated roller's teeth are worn severely, the area of the tooth top increases, resulting in an increase in the amount of glue applied, causing the surface or inner paper to be prone to deformation after adhesion;
7、The temperature of the corrugating roller, pressure roller or preheating roller is too high or too low, etc., it is easy to cause the corrugated paperboard to deform into a washboard shape after molding.
Solution
1、The moisture content of the original paper can be controlled within the standard range. When matching the paper, it is required that the moisture content of the surface paper, corrugated paper, core paper and lining paper be as close as possible to the range; properly use the surface paper, corrugated paper and lining paper with higher grammage;
2、Adjust the glue coating device to maintain normal working condition, keep the glue coating width of the ridge peak between 1.3mm-1.8mm, and avoid using too low speed for production;
3、Adjust the viscosity of the adhesive, increase the bonding force of corrugated cardboard during molding;
4、Replace the new corrugated roller, check whether the corrugated roller, pressure roller, guide paper plate, etc. are normal, if there is wear and looseness, take measures to eliminate them;
5、Check and adjust the heating device, and the machine using steam heating is prone to decrease in thermal efficiency and uneven surface temperature due to the accumulation of condensate water in the container. Therefore, for the machine with siphon device, the distance between the siphon device's suction port and the inner wall gap of the corrugated roller should generally be adjusted to 0.3mm-0.8mm, so that the condensate water can be discharged in time to maintain the appropriate temperature.
In summary, to prevent the occurrence of quality problems in corrugated cardboard, it is necessary to scientifically and reasonably master the production process, which is the most effective measure to improve the processing quality of corrugated cardboard.