When transporting goods in containers, static stresses are limited to the stack pressure generated by the goods themselves. This stack pressure load is caused by overstowing of the goods. The maximum "overstowing pressure" is a function of goods height and the internal height of the container.
Vertical, dynamic acceleration forces are superimposed on these static stresses. In unfavorable stowage positions, the acceleration caused by the pitching motion of the ship in maritime transport may amount to 1 g and, in extreme cases, even more. In order to withstand this additional load, the measured static pressure (see above) must be multiplied by a factor of two. When packaging is designed or calculated, further factors such as changing humidity, "untidy" stacking etc. are taken into account. Suitable packaging experts should be consulted when planning and making packaging.
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