As per ISO 11607-1, Compression test is one of the key performance testing that evaluates the interaction between the packaging system and the products. Compression strength is the measured maximum load a single container can withstand when tested in a static or dynamic compression test. Compression by static load, such as those stacked in a warehouse or DC are influenced by load, time, humidity, stack pattern, and pallet type and condition. When factors for handling, environment and storage are applied to the compression strength value, long-term stacking strength of a container can be estimated. ASTM D-642 (Standard method of determining compressive resistance of shipping container components of unit loads) or TAPPI T-804 (Compression test of fiberboard shipping containers) is the two test methods referred to perform the compression test study on Corrugated cartons.
The objective of this whitepaper is to understand the methodology of qualifying the compressive strength of corrugated carton boxes through simplified McKee’s equation. This methodology of qualifying the compressive strength is only applicable to the Regular Slotted Container (RSC) style of carton boxes. In McKee's formula, the empirical relationship is reduced by substituting the buckling load with the bending stiffness because they are almost proportional. McKee also found that there is a correlation between the material and geometric properties of the combined board and its bending stiffness. Through this method of simplified McKee's equation, compressive strength of RSC cartons can be identified theoretically and thus shall be considered as an acceptable method to qualify the carton boxes for market release
