Corrugated Flute

Corrugated Flute

Corrugated flutes are available in different standard shapes or flute profiles (A, B, C, E, F, etc.). A-flute was the first type developed and is the largest common flute profile. B-flute was then created next and is smaller in flute profile. C-flute followed and is between A and B. E-flute is smaller than B while F-flute is smaller yet.

​Basically, larger flutes provide greater strength and cushioning, while smaller flutes are more suitable for printability and foldability. Flute profiles can be mixed and matched within the same piece of combined board, to manipulate printability, compression strengths, cushioning strengths and the total thickness of the board.

For example, BE double wall gets its durability from its B-flute layer, while the E-flute gives it a smoother printing surface.

​Different corrugated flute profiles can be joined in one piece of combined board. For example, in a triple wall board, one layer of medium might be A-flute while the other two layers may be C-flute. Combining flute profiles allows manufacturer to control compression strength, cushioning strength, and total thickness of the board.

​The flute itself is usually manufactured from a waste based fluting (WBF – i.e., fully recycled material) or what is known as semi-chem fluting (SC).

Typical paper weights used for fluting are as follows:

  • 90 gsm WBF
  • 105 gsm WBF – Most Common Flute Standard
  • 112 SC and WBF
  • 175 SC and F

​There are also a number of commonly used flute profiles or sizes, which are as follows:
  • A FLUTE – 5mm
  • B FLUTE: 3mm
  • C FLUTE: 4mm
  • E FLUTE: 1.5mm
  • F FLUTE:.2mm
  • BC FLUTE: Double Wall – 6mm -Combination of B + C flutes
  • EB FLUTE: Double Wall – 4.5mm -Combination of E + B flutes

​Each liner type is actually comprised of two distinct layers. A basic layer is used as adhesion and strength, whilst a finer “cover” layer is used mainly for improved aesthetics and to aid printing.

Although Kraft and Test liners being so popular, there are in fact a number of other options. The available paper grades for outer and inner liners when manufacturing cardboard are as follows:

  • Kraft (K): Virgin Kraft paper
  • Test 2 (T2): Partly recycled liner paper
  • Test 3 (T):  Fully recycled liner
  • Chip (C): Waste based liners
  • Fully Bleached White (BW): Fully bleached Kraft liner
  • White Top (WT): White coated recycled liner
  • Mottled Kraft (MK): Mottled white Kraft

​Flow Packaging is an established supplier of supplying corrugated carton box of various flute specification to cater for different applications in Selangor, Kuala Lumpur, Seremban, Melaka and Johor.