notizie sull'azienda What is the production process of corrugated cardboard boxes?

The production of corrugated cardboard boxes is a fully automated assembly line operation, it mainly divided two parts: first make corrugated cardboard, and then use cardboard to make boxes and print patterns on them.

How to do it specifically? The process is divided into two steps as below:

Step 1: Production of corrugated cardboard
This step is completed on large corrugated cardboard production line.
Prepare paper rolls: Two types of large rolls of paper are mainly used: box board paper (relatively hard, used for the inner and outer surfaces of the box) and corrugated paper (elastic, used for the middle wavy interlayer).
Preheating: The paper roll first passes through a hot roller to evaporate some moisture, making the paper more flexible and adjusting the humidity for easier bonding later.
Squeezing waves (key point): The corrugated paper is pressed into regular wave shapes by a high-temperature corrugated roller (like two gears pressing against each other), and these waves are called "corrugations". The waves have both high and dense characteristics (such as common A-waves, B-waves, and C-waves), which determine whether the cardboard will withstand pressure and provide cushioning in the future.
Glue application and bonding: Apply glue (usually starch glue) to the top of the waves. Then, under pressure and temperature, stick the inner paper onto one side of the corrugated paper to make a single-layer corrugated cardboard. If thicker three-layer or five layer cardboard is needed, apply glue to the other side and stick the surface paper on as well.
Drying and cooling: The glued cardboard is subjected to a high-temperature and high-pressure zone, where the adhesive is thoroughly dried and solidified, allowing several layers of paper to firmly adhere together. Then quickly cool and flatten the cardboard, so that it is flat and strong.
Cutting: The wide cardboard produced continuously is first cut and trimmed according to the width required by the order using a machine, and then cut into pieces of board according to the required length using a computer-controlled cross cutting machine. So, the corrugated cardboard is ready.

Step 2: Forming and Printing of Paper Boxes
According to the order requirements, process the flat cardboard into the final cardboard box.
Printing: Most use the flexographic printing, which is fast and environmentally friendly with water-based ink. Print text, trademarks, and patterns on the surface of cardboard. If it is a particularly exquisite colored packaging, other more advanced printing methods may be used.
Slotting and crimping:
Line pressing: Press creases on the cardboard so that the folded box is neat.
Slotting: Cut out the openings on the lid and bottom of the box, and sometimes also cut the handle holes.
These two steps can usually be completed together by one machine.
Die cutting (if the box shape is special): If you want to make irregularly shaped boxes such as display boxes, you can use a specialized die cutting machine to stamp the cardboard into the desired shape with a mold with blades, just like stamping.
Nail box or adhesive box:
Nail box: Use a machine and galvanized wire to nail the joints of the box together. This is the most traditional and robust method.
Glue box: Use a machine to apply hot melt adhesive or white glue for bonding. The appearance of the box made in this way is smoother and more beautiful, without the problem of rusty iron nails, suitable for high-end packaging or automatic packaging lines.
After completing this step, the cardboard becomes a flat "box piece" that can be folded up, making it convenient for transportation and storage.
Packaging and storage: The pre-made cardboard boxes are flattened and stacked, bundled into packages in a certain quantity, labeled, and ready for storage and shipment.

So, the simple process is as below:
Paper roll → Preheating → Wave pressing → Adhesive bonding → Drying and cooling → Cutting into cardboard → Printing → Slotting, line pressing/die-cutting → Nail box or adhesive box (made into box pieces) → Packaging and storage
Several key points need to emphasize:
Paper quality: The thickness and strength of cardboard and corrugated paper directly determine whether the cardboard box is sturdy or not.
Wave selection: A wave has good buffering; B ridges are relatively flat and have high pressure resistance; C has good comprehensive performance; The E/F ribs are very fine and used for packaging small and high-quality items.
Adhesive: The formula and drying temperature control of starch adhesive are important.
Automation: Nowadays, production lines are mostly computer-controlled for size, temperature and speed, which is more efficient and precise.

In summary, this is the whole process of corrugated cardboard boxes from raw material rolls to final packaging.