A new development allows production of poly bags wound with the open end first at high-speed without air being trapped in the bags. Without compromising on efficiency, environment or profits.
The market for automatic bag inserting is increasing greatly, whether it is for e-commerce, food items, pharmaceuticals, industrial products, or similar packaging. Most of the bag packaging applications use inserter poly bags for hygienic, food safety and barrier protection purposes.
The challenge
When using poly bags in automatic bag inserter machines, it is desirable to unwind the premade bags with the bottom first (SOF = seal off first). This means that the opening of the premade bags comes out last and thus in the right position for automatic filling or inserting in a box. In many manual processes unwinding the roll with the bottom first could bring noticeable advantages, as this is the right position for filling the bag without needing to turn it around.
The industry has struggled with this for decades. Unwinding with seal off first means that the premade bags need to be wound with the open end first. The bag opening is wound in running direction, which often causes air to get trapped inside the bag before winding, resulting in fluffy and uneven poly bag rolls.
Until now, this challenge has been solved in different ways:
- Running with extremely low speed to avoid air being trapped inside the bags.
- Winding in a 2- step process, where the bags are wound conventionally in the first step and afterwards rewound with the bottom first.
- Punching holes in the bottom of the bags so that the air can escape before winding.
- Using static loading to “close” the bags in the winding process – this solution makes it difficult to open the bags in the automatic packaging machines.
These solutions end up being very costly. They are ineffective, labor-intensive and require additional power consumption.
The solution
Through extensive R&D and trials, Roll-o-Matic has found the solution to the decade long industry challenge with a technology based on existing machinery and without compromising the high degree of automation and operator safety that Roll-o-Matic solutions are known for.
The solution can be used both for in-line or out-of-line production. The process consists of the premade bags coming through the sealing machine without a perforation. Instead, the perforator is located just at the inlet of the winder, so there is a very short distance from perforation to winding, minimizing the risk of air getting trapped inside the bags. (Patent pending).
Increased sustainability
The winding is done fully automatically without the need of any pre-gluing on the cores. If your application requires that the bag is attached to the core, it is possible to do it without contaminating the cores. This feature allows you to reuse the paper cores several times, saving valuable resources and making your production more sustainable.
If you also need to run conventional bags on the winder, this is not a problem. Roll‑o‑Matic’s winder can do that. It is also possible to close the finished rolls with tape or labels. This way you can add production information to the rolls or make them ready for automated packaging solutions.
Would you like to learn more? Please visit us at the Pack Expo in Las Vegas, USA, on September 11-13. Be our guest and register for free using code 95Q41. We will be at booth SU-7649 in South Hall.
