The brewery Schützengarten AG of St. Gallen, Switzerland, was founded in 1779, making it the oldest of its kind in the beer-friendly country. Despite its vintage, the brewery is known for its investment in modern automation and technology. To produce the roughly 175,000 annual hectoliters of beer that it does, its lines need to be state-of-the-art.
Schützengarten recently replaced all of its dry automation systems in the bottling area, primarily in case erecting, case packing, sealing, and associated functions. KHS in nearby Dortmund, Germany, who served as integrator and general contractor on the project, selected a Gerhard Schubert case erecting and case packing system fitted with a Robatech adhesive application system.
When the new packaging line was first commissioned, the adhesive application portion consisted of two Concept Diamond type melters for manual filling with adhesive granulate and ten SX Diamond double jetting heads with corresponding heated hoses. In the first section of the packaging system, the erected corrugated cases are glued on the bottom fold and the sides. After that, the bottles are inserted into the corrugated cases. The last section glues the cover fold. Thus, the corrugated cases are sealed and ready for shipment.
Schützengarten uses the packaging system to achieve a throughput of around 27,000 bottles/hour. With manual granulated adhesive filling, this means that the operating personnel must refill the tanks of the two melters every 20 minutes. Though the tanks are equipped with level sensors and warn against idling, the staff must continuously monitor and be ready for refilling.
Compounding the issue, the tank of a melter can reach a temperature of up to 200°C. With manual filling at such high a frequency, the risk that employees could be burned grows over time.
And what's more, cold air flows into the tank during frequent opening and cools down the internal temperature. But only a constant hot melt adhesive temperature guarantees an optimal bonding quality. When these potential issues became apparent, Robatech technicians proposed a retrofit of the existing systems to an automatic filling system, namely the granulate feeder RobaFeed 3 and the associated granulate container, GlueFill L. The GlueFill L would be the largest variant from original to the retrofitted system.
Unlike with manual filling, the automatic filling process does not fill granulate directly into the hot tank of the adhesive melter. Instead it feeds into the granulate container GlueFill, which is unheated and stands separately. The GlueFill delivers the granulate into the melter tank as soon as the level in the tank is low.
“This is awesome for our employees and makes the job a lot easier. Safety is noticeably increased, and the employee in the line has more time for the corrugated cases. Despite our high bottling capacity, the granulate container only has to be topped up every two hours,” says Holger Gärtner, Head of Bottling at Schützengarten. “The automatic filling system for adhesive granulate has been running at full load from day one. It immediately paid off for us, as we can virtually eliminate production downtime in the packaging line.”
The RobaFill 3 and GlueFill run granulate with diameters up to 12 mm and pastilles with dimensions of up to 12 x 12 mm at a feed capacity of up to 4 kg/min. Feed distances have a vertical maximum of 2.5 m and a horizontal maximum of 7.5 m. Both run on 24 Volt DC from the system.
The GlueFill is available in 10-, 50- and 100-L sizes, with 1, 1 to 2, and 2 suction units respectively. The 6-bar, dry, cleaned, unoiled, G ¼-in compressed air connection runs at 250 standard L/min.