Computed tomography as a tool for tolerance verification of industrial parts

AbstractComputed tomography (CT) is becoming an important technology for industrial applications, enabling fast and accurate control of manufactured parts. In only a few minutes, a complete 3D model of a part may be obtained, allowing measurements of external and internal features. This paper presents results of tolerance verification of a plastic housing for an insulin pen manufactured by Novo Nordisk A/S. Calculation of measurement uncertainties was taken into account in decision making regarding the specified tolerance limits. Variables in terms of CT systems, data sets, and evaluation software are considered in this study

Verification of a CT scanner using a miniature step gauge

The work deals with performance verification of a CT scanner using a 42mm miniature replica step gauge developed for optical scanner verification. Errors quantification and optimization of CT system set-up in terms of resolution and measurement accuracy are fundamental for use of CT scanning in dimensional metrology. Influence of workpiece orientation, magnification, source-object-detector distances and surface extraction method on metrological performances of a CT scanner was evaluated. Results show that the position of the workpiece in the CT cabinet is fundamental to get reliable measurements, while the highest magnification (best resolution) does not assure the best accuracy