Matrix Channel Width Calibration for Matte Co-Extruded Film Converting
Calibrating matrix channel width to rule thickness plus 1.6 times composite caliper prevents matte skin fracture on co-extruded film laminated paperboard.
Matrix Clearance Formula
Tooling Specification
Engineering model used to determine the correct width of the channel in a creasing matrix ensures that the board can be folded without excessive stress. The matrix clearance formula accounts for the thickness of the board and the width of the creasing rule to define the geometry of the crease. This calculation is a fundamental step in the design of die cutting tools for folding cartons.
Mathematical Model
A standard version of the calculation adds the width of the steel rule to one and a half times the board thickness to find the ideal channel width. If a rule is zero point seven millimeters wide and the board is zero point five millimeters thick, the resulting channel width would be one point four five millimeters. Using a channel that is too narrow will cause the board to tear because there is not enough room for the displaced material.
A channel that is too wide will produce a weak crease that lacks a clear fold line. Operators may adjust the multiplier based on the fiber content or the coating of the specific material being processed.
Functional Reliability
Proper clearance prevents the surface of the board from cracking when it is folded at high speeds. It allows the carton to be formed with precise angles on the assembly line.