For large beverage companies, the advantages of self-manufacturing PET bottles can include increased efficiency, transportation savings and the use of the very latest blowmolding equipment. According to packaging experts, companies that fill in excess of 80 million to 100 million bottles per year may benefit from implementing in-line blowmolding.
 
In-house blowmolding is fairly commonplace in the U.S. bottled water industry, and some soft drink companies are beginning to bring bottle-making in-house as well. But Peter Andrich, executive director of food and non-food converter sales at KHS Corpoplast North America, Flemington, N.J., says hot-fill applications offer the biggest opportunity for cost savings.
 
“If you make a water bottle in house, you can save a lot of money, [but] this is comparatively little to what you can save in other applications,” he says. “We think the greatest amount of money that can be saved is probably in the hot-fill or in the juice industry.”
 
Hot-fill bottles, he says, lose a bit of their thermal stability in the time between blowmolding and filling. Blowing bottles directly on the production line eliminates that time in between.
 
“If you have no time in between making the bottle and filling, you retain your thermal stability, which means you can now run with a much lighter and more consistent bottle, actually at a higher speed and lower energy consumption,” he says. “You have several gains there.”
 
Nitrogen dosing offers even more material savings, he adds.
 
In-line blowmolding is more common in Europe and Asia, Andrich says, while U.S. beverage-makers have taken longer to adopt the practice.
 
“In Europe, unless you make that bottle in front of the filler, it’s hard to stay in business,” he says. “In America, this has not taken hold yet, but eventually it will because if bottling companies want to get their costs down, that’s the way to do it.”
 
KHS plans to announce a number of new blowmolding advances at the drinktec 2009 show in Munich that Andrich says will help drive further productivity and cost performance. In the United States, the company offers the InnoPET Blomax stretch blowmolder and the InnoPET BloFill stretch blowmolding/filling systems. They offer speeds appropriate for most industrial requirements, as well as low-energy hot-fill or high-precision preferential heating applications.
 
Block format
 
David Raabe, director of blowmolding and key accounts for Krones’ North American converter business, says beverage bottlers that use in-house blowmolding also benefit from block solutions that allow each component from the blowmolder to the filler to interface as a single unit.
 
One of Krones’ latest offerings is the NitroHotFill system, which allows for the use of round bottles on a hot-fill line.
 
“This is a bottle that is heat-set capable with no vacuum panels,” Raabe says. “This is a new technology that offers a lower reduction on container weight, up to 30 percent. This also gives you freedom of design for a round bottle, therefore labeling does not become a difficult performance issue as it does currently in the vacuum panel scenario.”
 
The bottles are blown on the Contiform H series blowmolders at speeds of 840 bottles per hour.
 
In addition, the company has created the NitroPouch, an ultra lightweight bottle that weighs 6.6 grams for a 500-ml. bottle. Most suitable for bottled water operations, the NitroPouch bottles can be nitrogen-flushed for stability, which allows them to be transported on regular pallets. The bottle also has no traditional neck ring, and features a 1.3 gram closure.
 
“It has a very lightweight finish,” Raabe says. “It has a very small grip area for easy labeling applications, and for a 6.6 gram bottle at 500-ml., it’s a very unique package.”
 
In addition to lightweighting, Raabe says high-volume beverage companies that self-manufacture bottles can control supply and demand more closely, and may benefit from smaller warehouse inventories. Fuel and transportation costs, as well as scheduling also can be more easily controlled.
 
“As you lower these costs as a self-manufacturer, you assure yourself an advantage over your competition,” he says.
 
All in one
 
Michael Fasold, director of business development and marketing at Sidel Group, Norcross, Ga., says in-line blowmolding and filling also can help enhance hygiene in a bottling plant.
 
Equipment such as Sidel’s Combi system offer a single enclosure and no intermediate equipment, which increases the hygiene potential. In addition, he says the system features automatic cleaning and sanitation of machine surfaces, a stainless steel construction and sloped walls that keep liquid from pooling, and possible vacuum dusting or decontamination of caps.
 
The system offers air flow protection of the filling and capping circuit, which can double the rate of air recovery and minimize energy consumption. And under aseptic conditions, additional considerations include a pressurized preform hopper, preforms that are grasped by the exterior of the neck, sterile oven air, laminate air flow at preform entry and bottle exit. It also can include preform decontamination with hydrogen peroxide, sterile water bottle decontamination, cap sterilization or UV sterilization for aluminum closures.
 
Elimination of air conveyors not only saves energy, Fasold says, but enhances design possibilities.
 
“Because of the neck handling and positive transfer of bottles between blowmolding and filling, the Combi is not bound by the limitations on the design of the PET bottles imposed by air conveyors,” he says. “This expands the possibilities for bottle shapes and lightweighting, which is key to reducing bottle costs since raw materials represent 65 to 80 percent of the total cost of an empty package.”
 
Fasold points out that the ultimate decision on self-manufacturing is a balance between volume, bottle complexity and operator skills. Those factors must align to be a better option than buying pre-made bottles. BI