How to ensure the adhesive strength of corrugated cardboard

The bad sizing is mainly related to the equipment state, adhesive quality, and quality of the base paper of the corrugated cardboard production line. The common quality problems caused by poor sizing mainly manifest in the following aspects:

1, the phenomenon of dripping

There are dirt on the rubber roller, such as paper scraps, agglomerates of starch and other foreign materials, etc., or the foreign material on the roll surface is blocked, causing the glue roller to fail to squeegee, and only a small amount of adhesive can be transferred, and it can be easily wiped. Falling, glue will appear at the peak of the glue on the lack of intermittent gluing phenomenon. The surface of the corrugated paperboard will be marked with layers of paper and core paper, and the compressive strength, side pressure strength and adhesive strength of the carton will be reduced.

When the gap between the upper and lower corrugating rolls is too wide, the upper roll cannot contact the lower corrugated roll and there is not enough adhesive on the corrugation peak.

2, adhesive lateral ejection phenomenon

Adhesive viscosity is too high; when it is too low or the content of borax is too high, lateral spraying of the adhesive is liable to occur when the production line runs at a high speed, which may cause warpage of the cardboard or softness of the cardboard, and adhesiveness and pressure of the carton. And the compressive strength will be reduced.

3, lead claw marks or vacuum marks

Traces of guide jaws or vacuum marks appear on the sizing part. The cartons made of such corrugated cardboard often break during use, and the side pressure strength of the corrugated cardboard and the compressive strength of the carton are greatly reduced. Corrugated cardboard produced by a single-faced machine with guide jaws often exhibits leader marks (a clear, adhesive-free blank) at the sizing section, usually due to bending, wear, misalignment or adjustment of the guide jaws. Large; the adhesive accumulates on the baffle and condenses into pieces, and these hardened starches will rub off the adhesive on the rollers and form traces of the guide jaws. In addition, the high moisture content of the corrugated paper, the abrasion of the wide adhesive on the glue roller due to wear on the glue roller, or the removal of foreign matter from the upper roller can cause this quality problem. Non-guided single-sided machines often have vacuum marks on the gluing section. This is mainly caused by too much vacuum in the corrugating roll. The vacuum will cause the corrugated base paper to be excessively affixed to the corrugating roll, causing the core paper to sag and the rubber roll cannot be used. The adhesive is applied to the ridges of the recessed core paper.

4, severely blurred intermittent glue application

This phenomenon occurs before the glue roller, mainly due to the distance between the guide jaw baffle and corrugated roller is too large, the guide jaw baffle is damaged or worn, the moisture content of the corrugated base paper is high, the pressure on the pressure roller is not uniform, corrugated roller There is dirt, the brake on the core paper paper is slack, the pressure on the corrugating roller is uneven or the pressure is too low, there is no vacuum on the corrugating roller or there is no vacuum temporarily.

5, irregular sizing shape

The irregular sizing shape is mainly caused by the unevenness of the corrugation caused by inaccurate position when the guide jaw and the core paper pass between the various rollers. The quality of the core paper, dirt on the corrugating roller, rough surface wear, and guide claws Wear, damage, bending, foreign matter on the guide jaws, lack of guide vacuum pressure or vacuum hole plugging, improper pressure on the pressure roller, too much or uneven brake tension on the core paper, etc.

6, lack of adhesive adhesive or no adhesive

Adhesive viscosity is too low, jamming of the rubber roller net, and gap between the rubber roller and the rubber roller are too small, which can lead to insufficient sizing. The gap between the rubber roller and the corrugating roller is too large, the steam condensate drips on the rubber roller, the adhesive liquid level in the glue amount is too low, the contact between the lower corrugating roller and the pressure roller is bad, and the height and position of the corrugating roller are not All will lead to no adhesion phenomenon.

7, adhesive gluing excessive

Adhesive sizing is usually due to excessive gap between the squeegee and squeegee, or excessive viscosity of the adhesive. Not only does the adhesive waste, but it also results in problems with slatted cardboard or warpage of the board, and in severe cases, significant wrinkling occurs.

8. The effect of corrugating roller on sizing

Corrugated rollers have depressions, dirt on the surface, damaged or worn corrugated rods, non-uniform corrugating roller clamping pressure, corrugating roller corrugation and non-parallel corrugation will affect the forming of corrugated, which will directly lead to poor sizing.

9, bad at the edge of the sizing

Corrugated cardboard longitudinally edged paper and corrugating medium are not bonded, and the looseness of the paper occurs. The main reason is that the slitting tool is not sharp, the slitting machine is running at a high speed, the slitting knife overlaps too much, and the slitting edge has a guide. Claw or vacuum marks, non-uniform moisture content at the edge of the tissue, uneven wear of the corrugating roll due to the difference in the paper web, and adhesive agglomeration on the pressure roller or the lower corrugating roller.