Effects of One-Point-Scoring Depth on Compressive Strength of Flap-Panel Structure of AB-Flute Corrugated Paperboard

Shigeru Nagasawa, Masanori Yamashita, and Haruya Yokoyama

Nagaoka University of Technology, Japan

Abstract: This paper describes the compressive strength and deformation behavior of folded flap-panel of corrugated paperboard (Cpb). In order to reveal the crushing mechanism of scored Cpb when varying the clearance of bite rolls, a low height flap-panel structure of AB-flute Cpb was experimentally subjected to a quasi-static compressive loading, and the side view of folded zone was analyzed using a video capture. When the panel height of 83mm was compressed up to 12-17% nominal strain, three referenced load points (1st inflection, 2nd peak and 3rd peak) were detected and its corresponded deformation patterns of folded zone were classified in even-slope, wall-digging and flap-digging with respect to the clearance of bite rolls. Also, compared two kinds of fixing condition (flap fixing: IF and wall corner fixing: IF+OF) of folded flap-panel structure, the relationship between the crushing deformation modes and three referenced load points was revealed. The case of IF+OF was apt to be 10~20% stronger than that of IF.

Key words: buckling strength, flap folding, double-wall, bulge, roll gap