The Effect of Corrugated Board Stacking on the Quality of Carton

The stacking of corrugated board is the process of heat-dissipating, heating, increasing adhesive strength, restoring the corrugation height, and preventing warp and warpage of the cardboard of the corrugated board production line. Therefore, the shape, height, environment, time and quantity of cardboard stacking, and even the pallet used directly affect the quality of the finished product box.
The following is a brief analysis of the above factors involved in stacking:
First, the impact of pallet stacking The carton industry is generally used is a wooden or hard plastic tray, the general specifications for the 1100 × 1200mm or 1200 × 1500, high 150 ~ 200mm. According to production practice, wooden pallets are preferred. The reason is that the wood pallet can absorb the moisture of the cardboard in contact with it during the stacking of the cardboard, and the plastic pallet does not absorb the moisture and is eventually absorbed by the cardboard which is in contact therewith, resulting in that the contact part of the facial tissue is damp, wrinkled or unglued. In addition, the height of the tray and the space between the slats on the tray are important ways for air convection after the stacking of the paper. The higher the height, the greater the gap, the more favorable the moisture distribution of the cardboard. However, taking into account the cardboard handling and the flatness of the stacking of the lower cardboard, the tray height is preferably 150-200 mm and the spacing between the strips is 100-150 mm.
Second, the stacking shape of the cardboard stacking code shape is nothing more than four: a single row of parallel stacking code; double row parallel stacking; well-shaped stacking stacking piling code; multi-row layered cross stacking code. The advantages and disadvantages are as follows:
1.Single-row parallel stacking Advantages: The board can be fully radiated up and down, and around four weeks; positive and negative ones can be used to make the cardboard smooth;
Disadvantages: Cardboard center heat can not be distributed in a timely manner, which soft peripheral hard; stacking middle and lower cardboard corrugated also because of its soft, after the pressure thickness thin; upper board easy bow waist deformation.
2. Double-row parallel stacking In addition to the advantages and disadvantages of single-row parallel stacking, the stacking code has the following advantages and disadvantages: it occupies less trays and saves storage space; heat between two cardboards is difficult to disperse, causing the cardboard to be hard and soft.
3. Well-shaped sub-stacking piling code advantages: good cardboard flatness, no warping, due to special stacking methods, there is a gap between the layers and the middle of the wells through the tray, the air circulation, heat distribution, Fast, good strength, less trays than the above two stacking codes, saving space.
Disadvantages: Occupies 2/5 of the area of ​​the cardboard overlap, moisture distribution is not complete; adhesive quality is slightly poor, the composite layer of paper is easy to crack; the number of cardboard between each layer will not be the same pressure deformation.
4. Multi-line layered cross stacking code Advantages: Compared with the above three stacking codes, the tray utilization rate is the highest, the floor space is the smallest, the cardboard flatness is the best, and the adhesive is slightly inferior and does not open the glue.
Disadvantages: paperboard hot air is not easy to disperse, making it soft; corrugated highly difficult to recover, cardboard due to thinning; due strength is also reduced, in severe cases, the thickness of five-layer paperboard dropped to 4mm below, three layers down to 2.5mm ( All other factors that affect the board thickness are normal.
Based on the above analysis, and considering the quality of the carton, it is obvious that the well-separated stacking piling code is the best choice.
Third, the impact of the number of stacking each ridge due to the corrugated board, the surface paper is not the same as the selection, the tension is also different, even if the production of cardboard even, heat cooling process will naturally warp. Insiders know that regardless of the stacking method chosen, the positive and negative stacking is the most orderly. However, in actual production, the number of positive and negative cardboards will not be the same, some ten, some dozens. The greater the number of defects, the more adverse the flatness and later adhesion of the cardboard, but stacking between positive and negative phases, wasting labor and reducing work efficiency. Therefore, five sheets of five-layer paperboard and ten sheets of three-layer paperboard are used as a product, which not only ensures quality and efficiency, but also facilitates the operation and facilitates the verification of quantity.
4. Effect of stacking height The higher the stacking height, the more space can be fully utilized and the space can be saved. However, the pressure on the middle and lower board is also greater, which is not conducive to the recovery of the corrugated height, and when the stacking height is severe, it affects the quality of the carton. And appearance. In particular, when the layout is not neat, it can easily cause unevenness in the cardboard. Such cardboard printing is not clear, and the slotting is also shallow and deep. After repeated verification, the stacking height is preferably 1.2 to 1.5 m.
5. The temperature, humidity and light in the stacking space affect the temperature of the stacking space. The higher the humidity, the faster the moisture absorption of the cardboard will be. After experiments, the air humidity is 60%, the temperature is above 30°C, and the cardboard can be returned to 30mm. All physical indexes such as soft and compressive strength are reduced by 30 to 50%. In addition, light has a degrading effect on the cardboard color, and strong direct light is particularly noticeable. Therefore, customers are required to use kraft paper, white coated paper and other fading surfaces. When making paper boxes, try to avoid strong light for a long time.
Sixth, the impact of time Cardboard stacking time is an important process of all layers of paper bonding, heat dissipation, increase the strength. If the stacking time is too short or the printing slots are produced at the time of production, the moisture of the cardboard is not yet completely discharged, and the adhesive does not exceed the full-stick time limit, and the paper guide rollers of the printing slotter press, corrugated, and stick. All layers separated by external forces will inevitably result in inferior quality of finished products. Therefore, the stacking time should not be too short. Generally, it takes 3 to 4 hours before entering the next process, and the minimum should not be less than two hours. To meet the urgent needs of customers, the 16800-flow axial-flow energy-saving fan can be used to force ventilation to shorten the stacking time. (Shan Xiaojing)