When carrying a heavy load, the priority is to minimize the risk of its exposure to a fall, impact or even sudden movements that may jeopardize its structural stability. For this purpose, a suitably thick package insulating against external shocks is indispensable.
Cardboard is the thickest paper material made of recycled paper and thicker wood pulp fibers. Its potential to withstand weights is very high. The strength of cardboard packaging is measured in a number of ways.
Flat Crush Test
The Flat Crush Test is a test during which a round cardboard sample is placed flat between the squeezing plates, and the pressure is increased until the wave deforms – thanks to which we obtain the strength of the material in kiloPascals and we know what crushing the packaging can withstand before the wave is crushed – and thus the strength cardboard box drastically reduced.
Edgewise Crush Test
The Edgewise Crush Test is based on applying pressure to a vertical rectangular sample in the direction of the load in the finished package – giving the result in kiloNewtons per meter at the moment when significant deformation occurs.
Box Compression Test
The Box Compression Test consists in compressing the finished box between two compression plates and observing the moment when the deformation occurs. Burst strength is also checked by pressing perpendicular to the surface on one side and determining when the sample breaks. Additionally, water uptake is also measured – by determining the Cobbs, that is, the increase in mass per square meter after absorbing a certain amount of water.
All these tests mean that it is possible to accurately determine how much pressure a given package can withstand. What’s more, cardboard boxes with a greater number of waves also have increased elasticity – if we plan to transport delicate items such as mirrors or glass decorations, the purchase of 3-layer cardboard boxes with walls almost one centimeter long may save the transferred content when there is an impact on the wall in contact with the goods.
Therefore, when buying cardboard boxes for carrying heavy loads or loads requiring stability, remember not to save on overgrowth on cardboard and carefully check what pressure a given package should withstand without any problems.
