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H, S, V or double flute: choosing the right PP corrugated sheet
The flute – the shape of the channels between the two skins – decides how a PP sheet prints, bends and carries load. Here is how to pick one.
Every PP corrugated sheet has two flat skins joined by ribs. The shape and spacing of those ribs is the flute. Two sheets of the same thickness and GSM can behave very differently depending on the flute.
H flute – the all-rounder
Straight vertical ribs. Light, stiff and easy to fold and weld, which makes it the standard choice for boxes, bins, layer pads and pallet liners.
S flute – for printing and standing upright
S-shaped ribs give a smoother surface and better resistance to bending. It is used for UV and screen printing, retail displays, and stiffening panels such as those inside delivery bags.
V flute – for rigid panels
Triangular ribs spread the load in two directions, so the sheet stays flat and rigid. It suits structural panels, signboards and dividers that must not sag.
Double flute – for heavy loads
Two layers of flutes in one sheet. It takes impact and stacking loads that a single-wall sheet cannot – heavy-duty boxes, bulk handling, pallet layers and crates.
Then choose thickness and GSM
Plasmix makes sheets from 2 to 11 mm and 270 to 3500 GSM. As a rule of thumb: thin, light sheets for printing and inserts; mid-range for boxes and bins; thick, heavy sheets for floor protection, shuttering and heavy loads. Tell us the load, size and use, and we will recommend the flute, thickness and GSM.