PETpla.net Insider 03 / 2016

INSPECTION 28 PET planet insider Vol. 17 No. 03/16 www.petpla.net by monitoring more parameters Detecting defects before they occur Preforms, closures and labels have to be top quality. In theory, this sounds so simple but in practice, this is difficult to ensure. In production, the defect rate can be from around 0.1% up to 10% when using recyclates. This is why inspec- tion systems are so important to help sort good parts from bad parts. But inspection systems can also help to prevent the bad from ever being produced in the first place. I NSPECT I ON S P E C I A L Separating bad parts from good is a classic aspect of quality control. But quality control can also do more: Correctly applied it can stop defec- tive parts from ever existing in the first place. Dr Gerd Fuhrmann, founder and CEO of Intravis in Aachen, Ger- many, pursues this extremely cost- effective approach with his inspection devices for closures, preforms, bot- tles, layers and decorations. Normally, a defect is discovered in production. At first only very small changes occur in the measured values, which still lie within the toler- ance range. It is only when they fall outside the tolerance limits that reject parts are detected. In order to be able to detect these extremely small initial deviations, however, it is necessary to have inspection systems with very high resolution. The data volumes must be analysed and presented at an appropriate speed. “The more data we have, the more we are able to detect the beginnings of defects,” says Fuhrmann. For the inspection of preforms, the PreWatcher III of Intra- vis is equipped with up to eight high- resolution cameras, making it possible to monitor up to 72,000 preforms per hour. It detects even smallest mate- rial defects, geometrical deviations, defects in the mouth ring and other features. Furthermore, it is able to read cavity numbers. But it is not just the early detec- tion of defects that promises an early return on investment. The accuracy of the defect detection ensures that if defective objects are in the production flow the smallest possible amount is rejected. Due to their lower resolution, conventional inspection systems have to have a wider defect tolerance range in order to be really accurate, whereas Intravis can keep the rejection window very small. Depending on the defect, this can mean an advantage of up to 1% of the total production. In order to monitor even more parameters, the company offers the Sample-PreWatcher, a system to inspect individual batches extremely detailed. Additionally to cavity number reading and material defects, it also inspects for contaminations, colour, weight, geometrical deviations and more. The remaining preforms can be sold on, because they have not been touched by human hand. In the cap segment it is also the case that the high-resolution cam- eras of the CapWatcher III produce a high volume of data which allows an accurate and, above all, early defect analysis. The performance here is up to 240,000 closures per hour, inspect- ing for ovality, sealing surface, con- taminations, reading cavity numbers and more. During the past few years, Intravis has grown by about 20% a year to 190 employees. Adapting the internal structures to growth time after time is the same great challenge for Fuhr- mann on the technological side. Last year, he brought Gabriele Fellerhoff on board as Quality Manager, who is – as is the norm now for the company – not seeking out mistakes. Instead she adapts their processes in such a way that problems are detected before they occur, according to the compa- ny’s vision. An important tool in this is the ISO 9001 certification, which has existed since the year 1999. A recurrent theme in company growth is laboratory and produc- tion space. It is not just the number of inspection systems being pro- cessed that is increasing but also their size. Despite the compact 8m² The Sample-PreWatcher: Detailed inspection of individual shots – also inline Intravis CEO Dr. Gerd Fuhrmann and quality manager Gabriele Fellerhoff: Together identifying problems before they occur