Agr Process Pilot advances GEPP light-weighting projects
With an Agr Process Pilot® Automated Blowmolder Control System mated to a Sidel SBO 16 Universal blowmolder, Mexican beverage producer GEPP has trimmed the weight of its 2L low-carbonation PET bottle from 52g to 46g. Given blowmolder operating speeds of 24,000 bottles per hour, the six-gram reduction is saving the company approximately seven tons of resin over each 48-hour production run.
This impressive weight decrease has been accomplished against a backdrop of shifting environmental conditions that add an extra layer of complexity to the blowmolding process. Despite temperature swings of 40 degrees or more throughout the day, Line 1 at GEPP’s Hermosillo plant, in the northwestern Mexico state of Sonora, turns out PET bottles that consistently hit the new light-weighted target as it operates around the clock.
Successful light-weighting demands rigorous adherence to the material distribution recipe developed for the bottle type. That is a lot harder to do when working with less material, observes GEPP Corporate Technical Manager Jesús López.
Introducing a new level of control over bottle-blowing, the Agr system provides the acute precision necessary to offset the impact of Hermosillo’s fluctuating temperatures. As López explains, “you don’t want to put the same amount of heat on a 90-degree preform as a 70-degree preform.”
Pilot’s high-precision sensors, deployed in the blowmolder takeout area, measure the thickness of each bottle at 12.5mm intervals along the sidewall. Agr’s proprietary algorithms instantaneously analyze the measurements and compare them to the recipe. If material distribution starts trending out of spec, Pilot adjusts the appropriate blowmolder function control—for example, tweaking the pre-blow setting or lamp temperature—to maintain consistent production. Eliminating the need for manual intervention, which is frequently an exercise in guesswork even for skilled operators; this automated fine-tuning makes sure the right amount of resin is distributed to the right area of the bottle, regardless of ambient conditions.
In addition to the bottom-line impact of less material consumption, the Agr system has enabled GEPP, the exclusive bottler of PepsiCo trademark beverages in Mexico, to make other major productivity gains, especially when it comes to changeover. Hermosillo’s Line 1 produces a mix of no-, low-, and high-carbonation bottles for six different products: Pepsi™, 7UP®, Mirinda (an orange-flavored soda), Manzanita Sol (apple flavor), Limonada (lime), and Epura (water)—in multiple sizes: 600mL, 1L, 1.5L, 2L, 2.5L, and 3L.
Changing from one container to another used to take an average of two hours—about 1.5 hours to replace the molds in the 16-station blowmolder, and then another half-hour for process verification and quality checks. Now, with the Process Pilot installed, the blowmolder produces good bottles on start-up, with no need for sampling and tweaking, making each changeover 25% faster—while also saving 6,000 bottles from scrap.
The benefits of robust bottle production also show up downstream in the integrated bottle-making and filling plant. López has noted far fewer disruptions in labeling, capping, and shrink wrapping due to non-conforming bottles. On the infrequent occasions when jams occur, “Pilot brings the process back to baseline two to three times faster,” he says.
A seasoned bottle veteran who was heavily involved in GEPP’s transition to PET from glass in the mid-1990s, López is responsible for all PET operations across the company’s 25 plants. Hermosillo, with its long-established history and talented operations team, represents the first site to mount a light-weighting initiative in conjunction with the Process Pilot. The success of that effort, in tandem with faster blowmolder start-ups, shorter changeovers, rapid jam recovery, and reduced scrap, has generated an attractive return on investment, not only on the 2L container but other sizes and types as well. Even more, it gives GEPP the confidence of improved bottle quality, which for López is the “paramount” consideration. Looking ahead, López would like to “standardize as much of the equipment and process as possible.” He nurtures the vision of installing the system on Hermosillo’s second blowing line and establishing the plant as the training site for all GEPP blowmolder operations throughout the country. “Process Pilot manages how the blowmolder makes the bottle so it always comes out the same,” López concludes.