In the works for several years, Agr International, Inc. has announced the commercialization of its CrystalView™ product for optimizing the material properties of PET bottles. The introduction of the CrystalView product further expands the capabilities and the potential of Agr’s Process Pilot® product group well beyond the measurement and management of material distribution. With this product, bottle manufacturers now have the means to 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 offers a simple, reliable and hands-free means to accomplish the optimization of PET material properties without overstretching or going beyond the temperature boundaries that cause molecules to break and create pearlescence. The CrystalView 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.
The CrystalView measurement 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. In conjunction 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. 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 CrystalView system also offers the potential for significant savings along with improved bottle performance in a number of areas including blower energy consumption (from 7-10%), materials savings through expanded light weight potential and Improved downstream efficiencies as a result of decreased downtime losses during filling and processing operations.
Three step blowmolder management
The CrystalView product is the third segment of the Agr Process Pilot blowmolder management product group. The Process Pilot product is based upon three fundamental concepts:
- Measure every bottle to identify variation,
- Control the blowmolder, proactively managing target distribution, to eliminate the effects of process variation
- Optimize the bottle structure for maximum performance.
The Measure and control portion of the Process Pilot program has been on the market for a number of years and boasts an installed base of over 200 systems. The CrystalView product fulfills the third segment, Optimization.
The CrystalView™ system is available as an add-on option to the Process Pilot automated blowmolder management system for all new purchases. A retrofit version is also available for Process Pilot systems currently operating in the field.
Agr’s Process Pilot automated blowmolder control system has proven to be a vital tool in the production of light weight bottles, while improving overall bottle performance and quality. It is unique in that it manages the blowmolder based on direct bottle measurements, on every bottle produced. By controlling the blowmolder based on direct feedback from bottle measurements rather than just blowmolder performance indicators, the Agr system can ensure that the final product has the desired quality and performance attributes in spite of environmental, blowmolder or material variations that occur during the production process. The CrystalView system further enhances the value of the Process Pilot product group.