Dynamic Crease Stiffness Reduction Ratios under Ultra High Speed Packaging Line Strain Rates
Dynamic crease stiffness reduction ratios must be evaluated under operational strain rates of 1000°/s to 5000°/s to prevent high-speed cartoning line jams.
Bottom Liner Splitting
Material Failure
Corrugated board structures undergo severe tensile stress on the outer convex surface when folded along pressed crease lines. During this sharp bending action, bottom liner splitting occurs when the tensile strength of the paperboard facings fails to withstand the elongation forced by the scoring matrix.
Stress Concentration
Scoring tools compress the internal fluting structure while creating a localized hinge point within the paperboard sheet. When the male scoring rule penetrates too deeply relative to the matrix channel width, extreme tension concentrates in the outer paper fibres during the final ninety degree fold. Recycled fibre furnishes with low average fibre length exhibit reduced elongation capacity, making them especially susceptible to fracture along the crease line.
Excessive tension pulls the outer ply apart before the internal fluting absorbs the bending deformation, exposing raw internal board layers along the package edge. Lowering scoring depth or widening the matrix gap redistributes tensile forces across a broader arc to preserve structural integrity.
Moisture Threshold
Paperboard humidity levels heavily influence fibre elasticity during high-speed folding operations. Dry ambient storage conditions reduce the moisture content of linerboard below five percent, causing cellulose bonds to become brittle under mechanical bending forces. Controlled relative humidity in converting facilities restores adequate fibre flexural endurance before scoring.