Improving productivity was a key theme of the seventh SPE European Thermoforming Conference, which was held in Antwerp in April, with presentations covering process control and the latest developments in in-mold labeling.
In a presentation titled “Getting thermoforming out of the black box,” Horst Dänzer — a former managing partner and CEO of thermoforming company ES Plastik Erwin Schmidt GmbH & Co KG of Bavaria, Germany — described the new Toolvision system he has developed to address the lack of recordable data in the thermoforming industry.
Dänzer described this lack of data recording as “the great disadvantage of thermoforming compared to injection molding.”
The Toolvision system aims to remedy the problem using dedicated sensors applied to new or existing tooling to measure, monitor and display thermoforming air pressure, vacuum, plug-assist position, tool strain and temperatures. It also provides an infrared measurement of sheet temperature and thickness. According to Dänzer, Toolvision users can increase production efficiency, cut scrap rates by 50 percent and protect machines and tools by monitoring set threshold levels.
Meanwhile, Reiner Albrecht, sales director at Heilbronn, Germany-based Illig Maschinenbau GmbH & Co. KG, provided delegates with an update on Illig's thermoforming in-mold labeling system, which was developed with the Austrian thermoformer Volpini De Maestri and was shown originally at the K 2007 fair.
The IML system has been operating in mass production for two years with Volpini De Maestri producing a 1-millimeter-thick, 200-gram polypropylene yogurt cup with offset printed in-mold labels.
The cup is thermoformed in a two-row, 12-cavity tool at 20 cycles per minute, giving an output of 14,400 cups per hour. Albrecht said that a heat-activated adhesive no longer is needed on the label, as the IML foil is hot enough to adhere to the PP cup body.
Volpini De Maestri is the only company using the Illig IML system at present, which Albrecht attributes to the difficulty in substituting the injection molded IML cups that have been in the market for as long as 20 years.
“We have to convince ex-thermoformers doing injection molding to go back to thermoforming again,” he said.
IML thermoforming is making international headway, however. In June, Klaus Wanner, sales and marketing director at Eching, Germany, automation specialist Hekuma GmbH, said it will be supplying a T-IML in-mold thermoforming line — based on a machine from TSL Thermoforming Systems — to U.S. company Tech II Inc. Hekuma is the provider of automation for Illig's IML system.
Springfield, Ohio-based Tech II will be the first company in North America to adopt IML thermoforming. TSL Thermoforming will show the T-IML system at K 2010 later this year.
In a separate presentation, Daniele Versolato, sales and marketing director for Solera Thermoform Group srl of Italy, described the development of thermoformed paneling for the PastItaly-brand “pasta espresso al dente” vending machine.
Launched by food-dispensing machinery producer Meccanica H7 of Italy in April, this machine serves freshly prepared pasta dishes within four minutes and is capable of delivering up to 300 portions.
Versolato said the eight thermoformed ABS plastic panels used for the metal-framed vending machine's housing are made using three different thermoforming processes — high-pressure forming, traditional vacuum forming and twin-sheet forming.
Design work started in November and the first prototypes, made in aluminum or polyurethane molds, were ready in February. Vacuum forming is used for the front panel and two lower floor panels, which are glued together and filled with foam, due to the need to incorporate some parts within the panel structures.
Foam and metal-frame cored twin sheet is used for the side panels to provide enhanced structural strength. High-pressure forming is used for the top panels to achieve the aesthetic appearance needed on the curved edges and the tight radii of defined fixing points.
Meccanica H7 is targeting sales of 800 machines in the first year alone, to a worldwide market. It claims the machine will pay for itself in months if it serves 60 portions a day or more.
Solera Thermoform Group is comprised of Solera Materie Plastiche in Florence, Italy, and Thermoform in Padua. It has 30 thermoforming machines and processes around 10 million pounds of plastics a year. The group is capable of producing twin-sheet thermoformed parts at up to 10 feet by 8 feet and traditional vacuum formed parts up to 13 feet by 5 feet.
Recognizing innovation
A key element of the SPE European Thermoforming Conference is the awards, which recognize innovative items produced using the technology, and the exhibition area.
Swedish thermoformer AB Formplast won an award for a soft-coated pressure formed ABS spotlight-lamp housing. The design overcomes the difficulty in the thermoforming process of getting sufficient material through a small tool opening, achieved through the use of two movable parts in the tool.
The Broby, Sweden-based company also entered a Volvo truck rear wall box, which is produced using a plug-assist pressure forming process in ABS to obtain a deep draw with good material distribution. Jacob Kunststofftechnik entered a deep-draw application in the form of its Easylift “Baby Wanne” CRS baby car-restraint system. The deep-draw PP “tub” for the seat shell is produced in a dual tool. The company said it has now finally achieved European EN standard approval, enabling the Easylift CRS to enter the market this year, initially in Scandinavia.
Cartolux-Thiers of France was awarded for its glycol-modified PET universal blister pack. This features a screw thread and is designed for packaging different size knee prostheses without additional pack inserts. Requirements included the ability to maintain its shape and stability after cutting, despite the large undercuts for the screw head.
In the food-packaging area, Danish thermoformer Faerch Plast was recognized for its crystalline PET Soup-in-the-Air airline pack, which is designed to replace conventional aluminum trays. The company claims it is the only plastic soup bowl and lid system available for this market sector. Design challenges included the need to keep the soup in the bowl while allowing air pressure to equalize during flight, as well as the requirement to release steam when heated for 20 minutes to 365°F. Both are met by the use of a groove around the top edge of the pack.
U.K. thermoformer Protective Packaging Systems entered its 360-degree all-round hard-drive packaging, which is made in white recycled high density polyethylene and is intended to replace foam or plastic end-cap solutions.
The company also submitted its clear amorphous PET Log-g clamshell pack for DIMM and SODIMM computer memory cards. The latter is made of an electrostatically dissipative A-PET material and features two diamond-shaped cavities to centralize up to 17 different card sizes in what the company calls “stalactite and stalagmite geometry.” This has saved 80 percent of space without compromising on protection, it claims.
Dutch thermoformer Batelaan Kunststoffen submitted parts for the Track T-800 diesel-powered motorcycle. Seven covers in thermoformed Senosan ABS/polymethyl methacrylate multilayer sheet, from Austrian sheet producer Senoplast Klepsch & Co. GmbH, substitute the polyester sheet molding compound used in the original design. The matte-black colored parts require no painting.
At the time of the SPE conference in April, Batelaan was in the process of finishing the production tooling. The Track T-800 CDI Black Edition was unveiled by its producer, EVA Products, at the Utrecht motor fair in February and will launch in the Dutch market later this year, with European-wide availability expected in 2011.
Another motorcycle application was submitted by Portuguese motorcycle plastics accessories producer Polisport Plasticos SA in the form of an in-mold decorated mud guard in PP. The project extends the company's established injection molding in-mold decal label capability to decoration of a complete thermoformed part. Italian thermoformer Solera submitted a twin-sheet formed tractor cab roof application in yellow ABS/PMMA and black ABS that is produced on a Geiss T8 thermoforming machine. Gluing of separate sheets has been eliminated in this project. The twin-sheet solution also eases assembly of air conditioning, lighting and various electrical equipment.
Twin-sheet parts by Hombach Wärmetechnik GmbH of Rosenheim, Germany, which recently took delivery of a Geiss T9 machine, were on display in the exhibition area. The T9 enables Hombach to produce twin-sheet in thin-wall and foamed core plastics and — through the use of halogen lamp heaters, servomotors and high-speed five-point toggle tool clamping — to do this on shorter cycle times.