Why does corrugated cardboard have a "washboard" phenomenon and how to solve it?

Corrugated cardboard is affected by temperature, adhesive, machine tension, and base paper quality, and is prone to washboard deformation. How to solve this?

　　Cause

　　1. The elasticity ratio of the fiber tissue of the base paper is quite different;

　　2. If the basis weight of the top paper or lining paper is low and the fiber structure of the base paper is too soft, the stiffness will be correspondingly poor after molding;

　　3. When the amount of adhesive applied is too much or uneven, there will be glue on both sides of the corrugated top. When it is bonded and dried with the top paper or lining paper, a certain torque will be formed on the top paper or lining paper due to shrinkage;

　　4. The viscosity of the adhesive is low, and it does not bond well with the fibrous tissue of the inner paper or facial paper to form a solid whole;

　　5. The gap between corrugating rollers and pressure rollers of single-sided or double-sided machines is uncomfortable and unbalanced;

　　6. When the corrugating roller's flute tooth tops are severely worn, the surface area of the flute tooth tops increases and the amount of glue applied increases, making the top paper or lining paper easily deformed after bonding;

　　7. When the temperature of the corrugating roller, pressure roller or preheating roller is too high or too low, it is easy for the corrugated cardboard to have a washboard deformation after forming.

　　solution

　　1. The moisture content of the base paper can be controlled within the standard range. When distributing paper, it is required that the moisture content of the surface paper, corrugated paper, core paper and lining paper should be kept as close to the range as possible; it is appropriate to use surface paper, corrugated paper and lining paper with a higher basis weight;

　　2. Adjust the gluing device to maintain normal working condition, keep the gluing width of Lengfeng between 1.3mm-1.8mm, and avoid using too low speed for production;

　　3. The viscosity of the adhesive can be adjusted to increase the bonding force during the molding of corrugated cardboard;

　　4. Replace the corrugating roller with a new one and check whether the corrugating roller, pressure roller, paper guide sheet, etc. are normal. If there is any wear and looseness, measures should be taken to eliminate it;

　　5. Check and adjust the heating device. For machines that use steam heating, the accumulation of condensed water in the container can easily cause a decrease in thermal efficiency and uneven surface temperature. Therefore, if the machine has a siphon device, the gap between the suction inlet of the siphon device and the inner wall of the corrugating roller should generally be adjusted to 0.3mm-0.8mm, so that the condensed water can be discharged in a timely manner to maintain a suitable temperature.

　　In short, in order to prevent the occurrence of quality problems in corrugated cardboard, it is necessary to master the production process scientifically and rationally. This is the most effective measure to improve the processing quality of corrugated cardboard.