In the works for several years, Agr International, has commercialized its CrystalView product for optimizing the material properties of polyethylene terephthalate (PET) bottles.
The product expands the capabilities and the potential of Agr’s Process Pilot product group beyond the measurement and management of material distribution.
With this product, bottle manufacturers can run the coldest possible process in order to optimize bottles material properties (orientation) while maintaining target material distribution.
As a result, the best strength to weight ratio for a given bottle design can be achieved, improving overall bottle performance and at the same time, reducing costs.
The CrystalView measurement system help to optimize PET material properties without overstretching or going beyond the temperature boundaries that cause molecules to break and create pearlescence.Â
The system manages the process to the point where it is ‘just right’; avoiding the creation of pearlescence by detecting the very edge of where the process gets too cold and pearlescence begins to form.
With CrystalView, it is possible to reduce the preform processing temperature to the ideal processing point (as much as 10 deg. C) for a given bottle design.
Operation
The system incorporates a set of discrete vision components that are mounted inside a reheat stretch blowmolder.
As bottles exit the mold, the CrystalView system scans every bottle for the onset of pearlescence.
During operation, sophisticated control algorithms incorporated into the CrystalView system actively monitor the levels of pearlescence.Â
With the Agr Process Pilot automated blowmolder management system, and based on a learned mathematical model that identifies the ideal control variables, adjustments are continuously made, including preform temperature, to manage bottle production to the point where the PET material properties are fully optimized, at a level just before the onset of pearlescence.
Improved bottle performance
Optimization of material properties makes it possible to create stronger, better performing bottles.
This is evidenced by recent field studies performed in production conditions on bottles manufactured utilizing the CrystalView system.Â
Test results showed significant improvements in bottle performance (as much as 38%) over bottles produced on the same blowmolder without the aid of the CrystalView system.
Some examples of the improvements experienced during this study include:
– Shelf life increased 10%
– Top load increased 17%
– Volume expansion (Creep) reduced 38%
– Burst pressure increased 17%
– Oxygen transfer rate performance improved by 7%
– Squeeze resistance increased by 7%
The system also brings saving such as blower energy consumption (from 7-10%), expanded light weight potential and improved downstream efficiency.
