Juxing Machine --What’s the solutions for the Automatic Flute Laminator paper board curling ?
In the process of carton laminating, there are two reasons for the paper curling defect：In a few cases the reason is the curling of the face paper and the corrugated paper itself, in most cases is the face paer and corrugated paper size changed because of absorbing the moisturethe in the glue and lead the defect during the laminating.
The more moisture that is absorbed, the greater the extent of its elongation. If the face paper scaling rate more than the corrugated paper, so the face paper upwarping after the laminating, in contrast will downwarping. If the water absorbed by the paper is completely precipitated, and the original moisture content is restored, theface paper will be alittle smaller than the original size, but the corrugated paper isalittle larger than the original size, and the shrinkage of the face paper is significantly higher than that of the corrugated paper and will lead the upwrapping.
And by observation, it can be found that the scaling ratio of the transverse direction of the paper is 10 times or more of the vertical direction. That is to say, if the length of the face paper or corrugated paper is the direction of the horizontal stripes and the width is the direction of the vertical stripes, the zise change will be greater, in contrast will be smaller.
Juxing Machinery-if the laminated paper curling serious will greatly affect the subsequent die-cutting work, resulting in die-cutting position remove, reducing efficiency, and even affecting the squareness after box forming, weakening the carton box Compressive strength, etc., so how to avoid curling after the laminating is an urgent problem to be solved. After analyzing the rule of curling, you can improve by the following three points:
First, improve the solid content of the glue. Since the face paper and corrugated paper size changed because of absorbing the over water and lead curling so we can choose the higher solid content glue. The higher the solids content of the glue, the less water it contains. Moreover, the glue with a high solid content can reduce the amount of glue applied per unit area of the paper and can reduce the the water absorb and can reduce the paper curling. 
Second, use the correct paper grain direction. In order to ensure that the paper does not have curling defects during the laminating process, it is necessary to ensure that the length is vertical and the width is horizontal, so that the paper size change will be small. Moreover, since the short side is the horizontal direction and the long side is the vertical direction, the absolute value of the web shrinkage is much smaller than that of the horizontal printing, so that the curling width can be reduced.
Third, choose the correct stacking method. In the process of laminating, the stacking of the laminated paper we choose the method: positive and negative manner can reduce the paper curling. For the laminated paper with serious curling, the  feasible and effective method is press the paper and after some time will be better.
it is more to apply a certain weight on it. After a period of time, the curled cardboard will be significantly improved.
As long as these three points are guaranteed, the problem of curling of the laminated paper  can be quickly solved, and the maintenance of the equipment should also be noted.