Robatech, stable palletizing without plastic

Currently, there is worldwide much focus on avoiding plastic. Where can we do without plastic without problems? Where do we have to develop alternatives first? Manufacturers and consumers are challenged. UFA AG, a Swiss manufacturer of compound feed, mineral salts, and milk powder, had already investigated in 2008, how to avoid plastic when palleting their feed sacks. At that time, the company opted for the innovative and cost-effective AntiSlip Gluing solution offered by Robatech. When a new bagging system was purchased for the specialty plant in Sursee in 2018, the palletizing process was put to the test once again: Should the pallets be glued again or shrink-wrapped in plastic film?

No passing on the plastic to the customers in the first place

Urs Steiner, Head of Production at UFA Sursee paid particular attention to a straightforward clarification: “We inquired within the company, and the decision was clear for hot melt adhesive application. Shrink-wrapping would require more effort, space, and, assuming a throughput of 25,000 pallets per year, higher material costs. Our customers must already dispose of the feed bags. They would then still have piles of film.” Urs Steiner knows what he is talking about. The delivery of palletized goods for animal feed preparation results in more than 2 tons of plastic film that must be disposed of yearly at the specialty plant.

Environmentally friendly stabilization

500 bags per hour are filled, sewn, and labeled in the new bagging plant. For subsequent palletizing, two AX-Diamond spray heads apply four hot melt spirals to the surface of the passing feed sack without contact. After that, a robot stacks layers of three sacks each on the pallet. Once two layers are stacked, a lift moves the pallet upwards and briefly presses the sacks against a press plate. This increases the adhesion between the layers, and the finished palletized stack can then be transported safely. Each layer is pressed, with the product counter of the Robatech application system ensuring that the last three sacks remain without adhesive application.

Automation needs reliability

“We aim for a high degree of automation,” says Urs Steiner. “Malfunctions cause work. We have many systems, and they all have to run without interruption. Our philosophy is not to look for the cheapest, but the most reliable solution. There is no unscheduled downtime with Robatech devices. If there is a problem, it is not relevant, or the service technician is available immediately. We are very pleased.”

Flexibility through modularity

UFA AG produces in a two-step process. In the mixing plant, the delivered powdery substances are weighed in batch mode, mixed homogeneously, and stored in a silo. In the next step, the powdery mixture is continuously blown from above into a spray tower and free-fall enriched with hot fat, which is sprayed laterally. The cold air introduced from below creates a crystalline, flowable product.

“With the new bagging system, we have been able to increase from eight to ten layers. That is a logistical advantage,” Urs Steiner describes the achieved efficiency increase.

“However, not only did the gravity-controlled pallet rack have to be modified, but the existing adhesive application process had to be adapted as well. In the past, we just glued on one side. That worked well. With the increase to ten layers per pallet, we had to increase the stability,” says the Head of Production at UFA describing the challenge. Robatech then equipped the existing Concept melter with two next-generation AX spray heads.

“Thanks to the high backward compatibility and the modular design of the Robatech products, that was no problem at all,” recalls Urs Steiner. “Beyond that, with the CoolTouch insulation on the Diamond application heads, you no longer have to burn your fingers. The energy efficiency is much better because the insulated application heads guarantee consistent adhesive temperature.”

Straightforward depalletization

Reliable gluing quality is crucial for safe palletization and straightforward depalletization. After all, the bags should arrive at the customer undamaged and be easily removed without tearing. Finally, Urs Steiner sums up his experience with the pallet stabilization solution from Robatech: “We are very pleased with the AntiSlip Gluing solution. The process is an excellent solution for us, for our customers, and for avoiding plastic waste.”

Read the article on Rassegna dell’Imballaggio International Issue

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