In order to ensure the strength and good adhesion of the corrugated board, the corrugated board should be adjusted according to the configuration of the corrugated board production line.
1. The corrugated forming is ideal when the moisture content of the corrugated paper entering the single-sided machine is controlled between 9% and 12%. When the corrugated paper moisture content is higher than the above indicators, it can be taken to increase the warm-up area or reduce the speed; when the corrugated paper moisture content is lower than the above indicators, spray can be taken to solve. The author believes that single-sided corrugated paperboard through the rapid transfer of paper on the bridge conveyor belt is positive ∞ type and consistent deposition distance, the original paper and corrugated paper moisture adjustment is better, the water content is more appropriate, single-sided corrugated cardboard stacked on the bridge The amount should not be too much, but in order to ensure that the double-sided machine does not shut down, the number of single-sided corrugated cardboard stacked on the flyover can be appropriately increased when the single-sided machine is changed paper.
2. The temperature of the dryer has a great influence on the water content of the corrugated board. The heating section of the corrugated board production line usually consists of three groups (four groups also). The number of heating plates is determined by the size of the heating plate and the speed of the corrugated board production line, and each group is provided with an independent control valve. To ensure that the moisture content of the single-faced corrugated cardboard before entering the dryer is basically the same, the size of the preheated area of the single-sided corrugated cardboard on the triple preheater can be adjusted. The adjustment method is: when the water content is too high, the preheat area increases; when the water content is too low, the preheat area decreases.
3. As the corrugated board production process takes away a lot of heat, a part of the saturated steam will become condensed water in the preheater and the corrugating roll and can be discharged through the steam trap. In order to ensure the normal discharge of condensed water, the author suggests that each The bypass pipe valve before the steam trap is opened every 4 hours for 3 minutes to 5 minutes to ensure the temperature is relatively stable. Controlling the amount of glue used to make corrugated cardboard is usually done with a corn starch binder. Its main ingredients are: corn starch, water, sodium hydroxide and borax. Due to the different configuration of the corrugated board production line, the speed is different, and the adhesive is prepared. The viscosity, concentration, and gelatinization temperature are also different. With the amount of glue applied, the moisture content of the corrugated board will also change. When the amount of glue is large, the water content of the corrugated board is large, and vice versa. For the single-sided machine and the double-sided machine, the gap between the rubberizing roller and the rubber limiting roller is generally 0.2mm-0.25mm; the gap between the single-sided machine and the rubber-coated roller is generally 0.1mm-0.2mm; the double-sided machine pressure The gap between the roller (touch bar) and the rubber roller should be slightly lower than the single-sided corrugated board height of 0.05mm to 0.1mm. The gap can be measured using a feeler gauge, but the two rollers should be parallel to each other.
With the change of temperature and relative humidity (summer and winter), the amount of rubber applied is also low. The reason is that the viscosity of the adhesive in the summer becomes thin, and the concentration can be adjusted by appropriately increasing the solid content. The corrugated paper with a high hygroscopicity and a low cyclic pressure index is used. Adhesives have poor fluidity in winter and can improve the temperature of the adhesive to ensure good fluidity of the adhesive. In addition to the above-mentioned factors affecting the strength of corrugated board, the responsibility of operators is enhanced and the operator's skill level is improved so that each operator can observe carefully and carefully adjust and strictly operate according to the process requirements to produce high Quality corrugated cardboard.
