By Bruce Geiselman
With brand owners and manufacturers looking to increase their use of recycled material, Husky has introduced an injection molding machine designed to provide optimal performance running high concentrations of recycled PET (rPET). Company officials said at NPE that the new HyPET6e also is energy-efficient.
“If you want to run rPET without compromising your quality, without seeing a degradation in your efficiency, that’s when you need the latest innovation,” said Dave Morton, VP of PET and packaging systems at Husky. “You can run rPET on an older machine, but you’ll still suffer in terms of your quality or cost.”
At the show, a HyPET HPP6e 400 produced a 5.89-gram, 100 percent rPET preform for a water bottle in 4.5-second cycles on a 144-cavity, 45-pitch mold, a configuration designed to enable production of up to 1 billion preforms per year.
An integrated drying system is among improvements to the new HyPET6e platform, to optimize its ability to process lightweight resin made of up to 100 percent rPET. The system includes the DRH920T + H7000 desiccant drying technology, with an inline metal separator and gravimetric blender.
“With rPET, you often get a little bit of metal contamination,” Morton said. “We want to separate that out.”
The drying system with metal separator is optional, but when ordered with the machine, it is fully connected to and controlled by the Husky HMI, and the dryer also can pull system processing variables and make adjustments, according to the company.
A new high-throughput screw design optimizes rPET melt quality while allowing uniform melt flow for applications involving lightweight preforms.
“There’s a whole new injection screw design, which we’ve changed in terms of how we introduce the material, how we meter it, how we compress it and how we mix it,” Morton said. “In past days, you’d have to pick between either the highest output in the injection screw versus the best mixing and the best melt quality. We’ve managed to combine those two designs so that you get high flow, in fact 7 percent higher than before, but you also get high mixing. You get the same high quality as our best mixing screw.”
An integrated, self-adjusting real-time inspection system provides closed-loop color correction and automatic color adjustments, which reduces the effects of rPET color variability.
“We’ve married an inspection system to the end of the machine,” Morton said. “As the preforms come off the conveyor, we’re doing inline inspections.”
The inspection system also can detect variations in preform dimensions, but, as of now, it cannot make automatic corrections to compensate for dimensional deviations.
The HyPET6e can automatically reduce energy consumption through a new adaptive technology that uses feedback from pressure and actuator sensors to calculate the optimum pressure required for different applications. The regenerative energy-management system automatically adjusts energy consumption without negatively affecting system capability, cycle time or part quality.
“We’ve actually taken a lot of energy out of the system — we’ve saved energy in the platform,” Morton said. “We’ve done this by separating different energy circuits within the machine for the injection side versus the clamp. We can run each on an on-demand basis. Depending on the application, you may need more energy in the clamp side holding the clamp shut while you’re cooling and freezing the material and less in the injection side. In the past, you’d have to run one energy level for the entire machine. Now, we can selectively lower based on what’s required. We call it on demand. We’ve also reduced energy use and improved efficiency across many other points of the system.”
The energy-management system can produce considerable reductions in operating costs for processors, he said.
An upgraded conveyor provides “gentle part handling” to minimize preform defects.
The system on display was equipped with Husky’s Advantage+Elite monitoring system that monitors equipment operation in real-time. It includes a suite of intelligent, connected solutions using end-to-end, closed-loop reporting to leverage data and analytics, optimize operations, reduce waste and improve overall equipment effectiveness, particularly when producing packaging containing higher percentages of recycled material.
In addition to the new injection molding machine, Husky also demonstrated a device used to form the tamper-evident band on PET closures. This device makes the mono-material (100 percent PET) beverage package a reality.
“It is a prototype we’re presenting here at the show,” said Michael White, director of business development, closures, at Husky. “We’re at the stage where we’re starting to look at early adopters.”
While most of today’s beverage bottles are made from PET, the closures are generally injection molded from HDPE, which is not ideal for recycling.
“With the bottle in PET and the closure in HDPE, the HDPE is typically downcycled into other non-food-contact applications,” White said. “It’s not truly circular. … When you have a PET package [closure and bottle], you have true circularity, and that brings us to the real fundamental innovation in beverage packaging.”
HDPE is more elastic than PET, making it well-suited to current tamper-evidence approaches. With PET, a “re-think” of closure design was required to achieve robust tamper evidence, White said.
Husky has developed a device that forms a tamper-evident band once the PET cap has been applied to the PET bottle. The opening experience with a PET closure offers a distinctive audible "crack" and a significant tactile response as the bridges break, and the tamper-evident band drop is clearly visible.
“This device is positioned on the filling line right after capping,” White said. “The closure is capped onto the bottle as normal. The capped bottles then pass through the forming device to create the tamper evidence. This approach offers a significantly higher level of consumer protection than what the industry offers today.”
Husky has been developing the capping system for more than a year and now is seeking early adopters. “We’re starting with still water because it’s one of the largest market opportunities, but it’s also the least challenging to start,” White said. “Then, we’ll progress into more challenging applications like carbonated soft drinks, hot-fill and aseptic.”
Using PET closures on PET bottles also can result in greater lightweighting, White said. Based on the material properties of PET bottles and closures, less thread engagement is required, and thread size can be reduced, which results in reduction of the overall neck finish height, he said.
Contact:
Husky Technologies, Bolton, Ontario, 905-951-5000, www.husky.co
