Analysis of the folding behavior of a paperboard subjected to indentation of a deviated creasing rule using the finite element method

This study reveals the crease deviation behavior through the developed forming simulation. A combination resistance model was expanded and applied to simulate the 180° folding process of a creased paperboard, using the shear-yield detaching resistance and the out-of-plane fluffing resistance which were based on the isotropic elastro-plastic model. When varying the misalignment of the creasing rule against the groove, the eccentricity of the crease bulging of a white-coated paperboard was compared through the experiment and simulation of the 180° folding process. Comparing the experimental deformation and the simulation, it was explained that the deviation of e contributed to making the crease deviation c_d. At the folding test, the 180° folding was compared with the experiment and simulation. The rolling pass of the folded zone was considered to intensify the deviation state. The 180° folding simulation revealed that the crease deviation of c_d ≈ 2e was assessed as an ideal condition when using the rolling pass and non-rolling pass. In the case of some shallow indentation in the experiment, 2e < c_d < 4e was observed. The inside folded corners were quite different between the simulation and experiment, especially for a certain shallow indentation model. In the simulation, the local crushing was not performed under the assumption of any isotropic properties. In the simulation, the deviation of the creased position at the 180° folding was sufficiently predictable, when compared with experimental behavior.