Characterization of Influences on the Wall Stability of Deep Drawn Paperboard Shapes

Abstract

Deep drawn shapes with orthogonal wall components are usually evaluated by shape accuracy and visual quality. There have been only a few investigations on the stability of such structures; however, the effect of the wrinkles on the stability of the wall is important for packaging applications and can support the shape accuracy. This paper focuses on the influences of process parameters on the stability of orthogonal walls of shapes produced by deep drawing with rigid tools and immediate compression. The wall stability was evaluated by tensile testing orthogonal to the direction of the wrinkles. The stability distribution was characterized with regard to the drawing height, and a comparison was made between the two different materials. The wall stability decreased with increases in the forming height. Furthermore, a blank holder force design and zdirectional compression level improved the wall stability. Together with an elevated moisture content of the material and thermal energy supply that delivered two to three times higher resistance against wrinkle extension, these effects drastically improved the wall stability.

Effects of press-forming parameters on the dimensional stability of paperboard trays

“…A combination of elevated mold tool temperature and blank moisture with sufficient compression in the forming of paperboard geometries improves the bonding of the paperboard fibers. The improved material bonding is associated with the enhanced dimensional stability, as the bonded fibers are more resistant to their stretching (Hauptmann and Majschak 2016).…”

The use and application of ultrasonic vibrations in the 3D deformation of paper and cardboard

“…The incorporation of process parameters such as tool temperature, forming parameters or material composition and humidity delivered improvements in the cup quality giving new confidence to bring paperboard into sufficient shapes in a widespread range of applications. The fixation of wrinkles in the wall of 3D-shapes can be significantly improved by increasing the tool temperature in combination with elevated material moisture and z-directional compression reached in the clearance between the tools (Hauptmann and Majschak, 2016).…”

Examination of the Transferability of Technological key Features of Paperboard Deep Drawing Towards the Application in Fast‐Running Packaging Machines

“…An optimized force trajectory closely connected to the punch position and adapted to the maximum endurable tensile load of the material at the infeed radius of the cavity leads to further improvement of the wall quality through a decrease of the wrinkle distances and an increase of the drawing height at the initiation of wrinkles . This blank holder force design also turned out to be of significant importance for the fixation in phase 3 of the process . The deep‐drawing technology was enhanced with the help of a servo‐hydraulic laboratory press at Dresden University which, in its current state, is not suitable for application as a packaging machine.…”

“…Furthermore, it is known that moisture plays an important role in the deep‐drawing process of paperboard. Elevated moisture leads to an improvement of the visual appearance and of the stability and fixation of the wall of 3D shapes . However, the typical way to achieve elevated moisture of paperboard is to store the material in high humidity.…”