What's New in Glass
February 1, 2007
What’s New in Glass
By Lisa McTigue Pierce
New techniques fire up functionality and aesthetics for this package staple
For 3,000 years, glass packages have protected and showcased a range of products, from foods and beverages to medicines and perfumes.
While the basic components — fire and sand — haven’t changed, the process of glass container manufacturing continues to evolve. Recent developments are giving glass container makers the tools to be more efficient, improve quality and add innovation. Benefits include competitive prices, premium packages and brand differentiation.
More efficient, better quality
Like other manufacturing operations throughout the world, glass container production has seen both process and technology improvements that deliver faster cycle times and more efficient changeovers.
To reduce downtime, improve productivity and ensure product quality, manufacturers are now capitalizing on:
• Servo mechanisms. Using servo technology gives manufacturers better speed control and more precise product handling. Benefits include greater production flexibility and faster operating speeds, which generally equates to higher output.
• Better temperature monitoring and control. Throughout container making (that is, forming a gob, pressing or blowing a parison, blowing the parison into a container and then cooling it), manufacturers are now able to save energy and better regulate predictive maintenance because of new ways to monitor and control temperatures.
Mark Delaney, vice president of research and development at Owens-Illinois, says the company has recently focused on measuring the heat transfer capability of the individual section (IS) machine more accurately, as well as improving cooling systems. O-I has also looked at more efficient metallurgy in the molds, which affects the heat transfer capability of the mold equipment. The machines are benchmarked on a common performance metric to identify potential opportunities for speed improvements.
Cycle times have also gone up at Vitro Packaging. According to Juan Farias, technology general manager, the company has been using new mold materials (such as minox and bronze) and incorporating more efficient cooling systems (such as axial cooling, vertiflow and vacuum) to enhance productivity.
• Better weight monitoring and control. Weight control starts with the gob. Here, again, servo technology is improving how gobs are formed and handled. Glass manufacturing supplier Emhart Glass, for example, recently upgraded its 555 AC servo feeder. New Multi-Cam software allows the servo feeder to produce gobs of different weights in different machine sections during forming.
And, although not yet in production, Emhart is also testing a quadruple-gob machine that can produce four containers at the same time. This would boost gob output by a third compared with the world standard triple-gob machine.
Several glass container makers have invested in press-and-blow systems because the technology has the potential to reduce both glass and energy usage, and improve product quality. Rather than using air to form the gob into a parison (as in blow-and-blow manufacturing), the increasingly popular press-and-blow process uses a plunger to push the gob into the mold. This way, manufacturers can better regulate glass thickness, either evenly distributing it or making it thinner or thicker in various areas as needed.
• Computer modeling. New software that simulates the manufacturing process lets glass container manufacturers optimize the package’s geometry, wall thickness, internal pressure and vertical impact prior to mold making and production.
• New glass conditioning technologies to lightweight, strengthen and/or add performance. Although glass manufacturers have lightweighted containers nearly 30 percent in the past 10 years, development efforts still continue. The challenge is to lightweight without compromising strength or quality.
Advancements here deal with the raw materials and new technologies, but some are also process related. As Doug Trenkamp, project manager for product development and innovation at O-I, explains, “Anytime you improve process consistency, you might be able to lightweight.”
Glass container forming equipment specialist Quantum Engineered Products has developed a vacuum-assisted method to improve the results of conventional blow-and-blow manufacturing. According to the company, its Advanced Blow & Blow with AFCON (ABB/A) process has shown an 18 percent to 24 percent reduction in weight versus standard blow-and-blow manufacturing. Cavity cycle rates increased up to 60 percent, too.
Other glass conditioning equipment vendors are looking at radio frequency and microwave technologies. BHF Engineering, for example, has tested microwaves, which reportedly offer better thermal and chemical homogeneity. (BHF is also looking at using microwaves to melt, and perhaps stir, colorant into the glass.)
On the materials side, Vitro’s Farias describes techniques under development that involve the chemical deposition of steam and nanotechnology to simultaneously lightweight and strengthen.
Additives and coatings are another way manufacturers expand performance options of glass containers. For example, product marketers continue to ask for clear packages that protect their products from damaging ultraviolet (UV) light. According to Trenkamp, O-I has responded to this demand by focusing on exterior coatings (the traditional method today) and on batch raw materials to chemically create absorption centers for UV light, essentially blocking it from reaching the product.
Equally important to all these manufacturing improvements are the myriad innovations in container design. Glass not only provides a “consumer-preferred” premium look and feel, but it also offers almost unlimited freedom in container shape design.
New aesthetic techniques continue to provide opportunities for brand differentiation. Among them are:
• Internal embossing. Available from O-I, this “inbossing” creates a unique look that’s affordable. Trenkamp says, “The obvious benefit of doing [the decorating] during the molding process is that it becomes more of an in-line step. So the economics of it are pretty attractive.”
• Etching. The Satin Etch process from Rexam Glass, for example, offers an effective way of creating a smooth, high-quality matt frosted finish.
• Antiquing. To make packages for nostalgic products look vintage, O-I molds thicker sidewalls and bases and ripples the surface.
Yet even an old-fashioned container design can benefit from modern computer technology. A major initiative now underway at O-I centers on developing a web-based design collaboration program. The initial push is to create a library of mold designs. From there, engineers and marketers can capitalize on previous designs instead of remaking the wheel each time. Trenkamp says the benefits of this “knowledge-based engineering” process will be lower costs and quicker mold production.
While few in number, today’s glass container manufacturers offer many innovations to keep this ancient package fashionable and competitive.
Lisa McTigue Pierce is the editor-in-chief of Food & Drug Packaging, Beverage Industry’s sister publication.
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