However, in certain cases it is becoming more and more important to control this issue even better. When going through further production steps like tempering or bending, the surface evenness can gradually decrease. If such irregularities go unnoticed, value is added to non-saleable products and manufacturers waste large amounts of money – respective financial losses have been known to go as high as the six-figure range. There is finally a way to stop the expensive processing of defective material once and for all: PowerPlate (P²)-3D, a cutting-edge product dedicated to non-contact 3D form measurement of glass plates. It is part of the modular PowerPlate (P²) product line designed for inspection and quality optimization in glass plate manufacturing.
The claim for flawlessness will always have top priority for customers – with good reason: The quality of the glass plate not only impacts the product's visual appearance, but also plays a significant role in terms of functionality and safety. The fact that the product evenness can decrease with every single production step makes it even more important to establish a strict quality control. However, the automated monitoring of a glass plate’s form and evenness could not be reliably solved with previously available technology.
P²-3D is powered by ISRA’s over 30 years’ worth of experience in optical glass inspection and utilizes high-end Stereo Deflectometry. The innovative extension of classic deflectometry ultimately enables the real full-surface 3D measurement of glass sheets of virtually any size. It is uniquely accurate and robust for use in industrial environments. Introducing 3D inspection, the technology adds another dimension to the quality control of flat or bended glass sheets. As a consequence, all defects and irregularities in regard to form and evenness of the glass are detected 100%.
A measuring tolerance of ± 0.05 mm is achieved. The reached repeatability of the local slope is within the range of a few arc seconds. Built into a compact system setup, P²-3D may be integrated directly into the production line, allowing for the quality control to be performed in-process. The sample’s position can be adjusted at will. No longer does a sheet have to lie flat on the conveyor. It may in fact be tilted freely in x-y-z direction. The measurement tolerates deviations up to the centimeter range.
Additionally, the advanced optical inspection solution can be combined with software features for data analysis to achieve considerable efficiency improvements. The systems measure, analyze and classify all form of deviations automatically. Recorded information in shape of defect statistics, color coded maps and defect images are stored centrally in the data base. Compiled into inspection protocols, they grant users valuable insights into production.
Full process control is the result: Inspecting glass plates within short cycle times ensures optimized processing and helps to keep production conditions stable. This guarantees highest possible quality and a boosted productivity, improving cost effectiveness and competitiveness. P²-3D inspection systems are already in use in several areas such as special applications for architectural glass or ceramic glass for cooktops and even more.