Thermoforming has benefited from applications of engineering technology,although the basic forming process is very similar to what was invented many years ago. Microprocessor and computer controls on more modern machinery allows for greatly increased process control and repeatability of same-job setups from one production run to the next, usually with the ability to save oven heater and process timing settings between jobs. The ability to place formed sheet into an inline trim station for more precise trim registration has been hugely improved due to the common use of electric servo motors for chain indexing versus air cylinders, gear racks, and clutches on older machines. Electric servo motors are also used on some modern and more sophisticated forming machines for actuation of the machine platens where form and trim tooling are mounted, rather than air cylinders which have traditionally been the industry standard, giving more precise control over closing and opening speeds and timing of the tooling. Quartz and radiant-panel oven heaters generally provide more precise and thorough sheet heating over older cal-rod type heaters, and better allow for zoning of ovens into areas of adjustable heat.
The more than USD10 billion North American market has traditionally been ¾ thin gauge and ¼ heavy gauge. In 2003 there were about 150 thin gauge thermoformers in North America. Sixty percent formed proprietary products. Thirty percent were custom formers and 10 percent were OEMs with in-house forming capability. There were nearly a dozen thin-gauge formers having annual sales of at least USD100 million. The largest had annual sales in excess of USD1,000 million. There were about 250 heavy gauge formers in North America. Nearly all were custom formers. Only two or three heavy gauge formers had annual sales of more than USD100million. The largest had annual sales of about USD140 million
Monday, November 10, 2008
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