How to ensure the bonding strength of corrugated b

How to ensure the bonding strength of corrugated paperboard

poor sizing is mainly related to the equipment status of corrugated paperboard production line, adhesive quality and base paper quality. The common quality problems caused by poor sizing are mainly manifested in the following aspects:

1. Dot sizing phenomenon

dirt on the top roller, such as paper scraps, starch caking and other foreign matters, or foreign matters blocking the hole on the roller surface, which leads to the failure of the top roller to glue smoothly, Only a small amount of adhesive can be transferred, and it is easy to be wiped off. When gluing, there will be insufficient glue on the Lengfeng. It is promised to respond to the customer's problems within 2 hours, and there are intermittent drops of glue. Such corrugated board surface will appear the traces of lamination of face paper and core paper, and the compressive strength, edge compressive strength and adhesive strength of the carton will be reduced

when the gap between the upper rubber roller and the lower corrugating roller is too wide, the upper rubber roller cannot contact the lower corrugating roller, and there is not enough adhesive on the corrugating peak

2. Lateral ejection of adhesive

the viscosity of adhesive is too high; When the borax content is too low or too high, the horizontal ejection of adhesive is easy to occur when the production line is running at high speed, which will cause the cardboard warping or the cardboard softening, and the adhesion, edge pressure and compressive strength of the carton will be reduced

3. Guide claw marks or vacuum marks

there are guide claw marks or vacuum marks in the sizing part. Such cartons made of corrugated cardboard will usually break when in use, and the edge pressure strength of corrugated cardboard and the compressive strength of cartons will be greatly reduced. The corrugated board produced by the single-sided machine with guide claws often has guide claw marks (a clear blank without adhesive) in the sizing part, which is usually mainly due to the bending, wear, position deviation or high adjustment pressure of the guide claw baffle; The adhesive accumulates and condenses into blocks on the baffle, and these hardened starch will wipe off the adhesive on the rubber roller, forming a blank trace of the guide claw. In addition, the high moisture content of the corrugated base paper, the groove on the top roller caused by wear, or the wide adhesive on the top roller is wiped off by foreign matters, will all lead to this quality problem. Vacuum marks often appear in the sizing part of the single-sided machine without guide claws, which is mainly caused by too much vacuum of the corrugating roller. The vacuum will over stick the corrugated base paper on the corrugating roller, causing the core paper to be sunken, and the glue roller cannot apply the adhesive to the sunken core paper ridge peak

4. Severe fuzzy intermittent sizing phenomenon. He has been fighting for the development of the experimental machine for more than 10 years.

this phenomenon occurred before the rubber roller, mainly because the distance between the guide claw baffle and the corrugating roller is too large, the guide claw baffle is damaged or worn, the water content of the corrugating base paper is high, the pressure on the pressure roller is uneven, there is dirt on the corrugating roller, the brake on the core paper base paper is loose, the pressure on the corrugating roller is uneven or too low There is no vacuum on the corrugating roller or temporarily

5. Irregular sizing shape

irregular sizing shape is mainly caused by the uneven corrugation caused by the inaccurate position of the guide claw and the core paper when they pass between various rollers. The quality of the core paper, dirt on the corrugating roller, rough surface wear, wear, damage, bending of the guide claw, foreign matters on the guide claw, no insufficient vacuum pressure of the guide claw or blockage of the vacuum hole, improper pressure on the pressure roller The braking tension on the core paper is too large or uneven

6. The market demand for adhesive is very strong. Insufficient or no adhesive

the adhesive viscosity is too low, the hole of rubber roller is blocked, and the gap between rubber scraping roller and rubber roller is too small, which will lead to insufficient glue. The gap between the upper rubber roll and the corrugating roll is too large, the steam condensate drips on the upper rubber roll, the adhesive liquid level in the glue volume is too low, the contact between the lower corrugating roll and the pressure roll is poor, and the middle height and position of the corrugating roll are inaccurate, which will lead to the occurrence of no adhesion

7. Excessive glue application of adhesive

excessive glue application of adhesive is usually due to the large gap between the glue application roller and the rubber scraping roller, or the high viscosity of adhesive. It will not only cause the cost of adhesive, but also lead to the problem of washboard paperboard or the warpage of paperboard. In serious cases, there will be obvious wrinkles

8. Influence of corrugating roller on sizing

there are depressions on the corrugating roller and ouyangming on the surface, which means dirt, damage or wear of corrugating rod, uneven pressure of corrugating roller clamp, and uneven corrugation of corrugating roller will affect corrugating molding, directly leading to poor sizing

9. Poor sizing at the longitudinal cutting edge

the face paper at the longitudinal cutting edge of corrugated board is not bonded with the corrugated core paper, and the face paper is loose. The main reasons are that the longitudinal cutting tool is not sharp, the longitudinal cutting machine runs over speed, the longitudinal cutting knife overlaps too much, the longitudinal cutting edge has guide claws or vacuum marks, the moisture content of the face paper edge is uneven, and the corrugating roller wear caused by different base paper webs is uneven There is adhesive caking on the pressure roll or the lower corrugating roll