Eric asks –
What is the correlation between the paper substance (of the liners and flutes) and the bursting strength?
Take for instance of a double wall board – What would be minimum values(g/m2) of the substances for the flutes and outer, inner and middle liners in order to achieve a burst strength value of 350lbs?
Thank you for your question Eric.
Burst is dependent on the substance and other physical properties of the lines and not the flutings or caliper of the flutes.
To develop burst strength in liners requires long fibres, clean fibres, well developed fibres from the stock preparation area, and good fibre formation on the paper machine. Many good bonding sites among the fibres is critical to burst. So, generally the more bonding sites, or substance, the higher the burst strength. Lacking some of the above, the addition of starch or other paper making chemicals will form chemical bonds between fibres where mechanical bonds would normally occur.
Burst strength and substance are very poor indicators of box performance and stacking strength.
– Ralph