English
A used 7 ply corrugated production line is an industrial system designed to manufacture high-strength corrugated cardboard with seven layers, commonly used for heavy-duty packaging applications. This type of production line consists of multiple interconnected machines that process raw materials into finished 7-ply corrugated board, offering cost-effective and efficient operations. Understanding the working principle of a used 7-ply corrugated production line helps businesses optimize production and ensure high-quality output.
1. Raw Material Feeding and Preparation
The process begins with the unwinding of kraft paper rolls, which serve as the linerboard and medium for corrugation. The production line consists of multiple roll stands that feed these paper rolls into the system. The linerboards form the outer and inner surfaces, while the medium layers are later corrugated to provide strength and flexibility.
2. Corrugation Process
The heart of the production line is the corrugator unit, where the medium paper is transformed into fluted (wavy) layers. This process involves:
Heating: The paper is preheated using steam to make it more pliable.
Corrugating Rolls: The heated paper is passed through corrugating rollers, which shape it into a fluted structure.
Adhesive Application: A starch-based adhesive is applied to the peaks of the flutes to bond them with the linerboard.
This process is repeated multiple times to create the five corrugated layers needed for a 7-ply board.
3. Layer Bonding and Lamination
After individual corrugated layers are formed, they are laminated together using strong adhesive. The linerboards are placed on the top and bottom surfaces, while multiple fluted layers are sandwiched in between. The pressing section ensures proper adhesion and eliminates air bubbles, resulting in a rigid, multi-layered structure.
4. Drying and Cooling
Once laminated, the 7-ply corrugated board passes through a heating and drying section, where the adhesive is fully cured. This step enhances the board’s durability and prevents delamination. After drying, a cooling section ensures the material stabilizes before further processing.
5. Cutting and Stacking
The final stage involves cutting the large corrugated sheets into precise dimensions using a slitter-scorer and cross-cutter. These machines ensure uniform sizing based on customer specifications. After cutting, the sheets are automatically stacked and prepared for transportation or further conversion into packaging products.
Advantages of a Used 7 Ply Corrugated Production Line
Cost-Effective Investment: Purchasing a used production line reduces costs while maintaining high efficiency.
High Strength and Durability: 7-ply corrugated board provides excellent load-bearing capacity for industrial and export packaging.
Scalability and Customization: The production line can adjust flute sizes, adhesives, and paper grades for customized packaging solutions.
Eco-Friendly Operation: Uses recyclable kraft paper and starch-based adhesives, making it an environmentally sustainable option.
Conclusion
A used 7 ply corrugated production line operates through a systematic process of corrugation, lamination, drying, and cutting, ensuring the production of high-strength cardboard for heavy-duty packaging. Businesses looking for cost-effective and reliable corrugated board production can benefit from investing in a used system while maintaining high efficiency and sustainability. With proper maintenance and optimization, a used production line can continue to deliver high-quality output for years to come.
