Shape accuracy analysis of deep drawn packaging components made of paperboard

Process development for the production of paperboard cups requires methods to capture the shape accuracy with fast, reliable and easy to apply measurement procedures. This publication aims to present a measurement method and an analysis of the influence of important parameters on the shape accuracy of deep drawn cups. Therefore, a shape accuracy analysis is developed and the precision of the measurement and influence of the operator are examined in detail. The method is applicable for cylindrical and non-cylindrical shapes and outputs a value to characterize the shape accuracy of a sample. A parameter studies is presented that covers the most important influencing parameters: blankholder force, punch and die temperature and moisture content. The temperatures of the forming tools are found to have a significant effect on the deviation from the required form. Furthermore, the results indicate that the blankholder force, which is highly important to control the formation of wrinkles, does not have a significant effect on the shape accuracy.