Make Bottles by Vertical Thermoforming
Sheet is formed into a tube and then into bottles.
At NPE2015 last month, Serac Inc., Carol Stream, Ill., introduced technology to make bottles on a vertical thermoforming machine. The technology relies on a tubular thermoformer built by France’s Agami that permits bottles to be produced from sheet rollstock. The machine was originally designed to make PS yogurt cups. Serac says the Agami former can produce bottles from PS or PP roll stock. The novelty here is vertical thermoforming of bottles. A horizontal version, called Bottleform, was introduced by Illig in 2008.
Bottles produced on the Agami thermoformer are said to look the same as blow molded bottles. In the vertical thermoforming process, sheet is first formed into a tube, which is heated and blown in the mold to form a bottle. As a result, bottles are not limited to large necks and small heights, but can be made into the round designs that are more common today. The bottles also show a better resistance to vertical compression than those produced using flat thermoforming, Serac says. Vertical thermoformers have a smaller footprint than horizontal machines.
Compared with blow molding, this system makes storage tanks and unscramblers unnecessary, as the bottle goes straight from the former to the filler. Even sleeve applicators are no longer necessary, since the technology can process printed sheet.
Serac says that producing bottles from rollstock saves throughout the supply chain, from manufacturing to transport to storage. The Agami technology also consumes far less energy than other blowing systems, as bottles are blown at less than 90 psi and under 302 F, Serac claims.
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