Types of Corrugated Board: Complete Guide to Flutes and Structures

Corrugated board comes in many types, each designed for specific applications. Understanding these types helps you choose the right packaging solution.

What is Corrugated Board?

Corrugated board (also called corrugated cardboard or corrugated fiberboard) consists of:

• Liner: Flat paper sheets on outside

• Medium: Wavy paper in between (the flutes)

• Adhesive: Bonds liner to medium

The fluted structure provides strength-to-weight efficiency unmatched by solid materials.

Flute Types Explained:

A-Flute:

• Height: 4.8mm (3/16 inch)

• Flutes per foot: 33

• Characteristics: Best cushioning, highest stacking strength

• Applications: Fragile items, furniture, appliances

B-Flute:

• Height: 2.5mm (3/32 inch)

• Flutes per foot: 47

• Characteristics: Good printing surface, puncture resistant

• Applications: Canned goods, retail displays, die-cut boxes

C-Flute:

• Height: 3.6mm (9/64 inch)

• Flutes per foot: 39

• Characteristics: Balance of cushioning and printability

• Applications: Most common shipping boxes, general packaging

E-Flute:

• Height: 1.2mm (3/64 inch)

• Flutes per foot: 90

• Characteristics: Excellent printing, thin profile

• Applications: Retail packaging, pizza boxes, shoe boxes

F-Flute:

• Height: 0.8mm (1/32 inch)

• Flutes per foot: 128

• Characteristics: Superior print quality, replaces folding carton

• Applications: Fast food packaging, cosmetics, small retail

Wall Structures:

Single Wall (3-Ply):

• Structure: Liner + Medium + Liner

• Flute options: A, B, C, E, or F

• Weight range: 200-600 gsm

• Applications: Light to medium duty shipping

Double Wall (5-Ply):

• Structure: Liner + Medium + Liner + Medium + Liner

• Common combinations: BC, EB, AC

• Weight range: 400-1000 gsm

• Applications: Heavy products, stacking loads, export

Triple Wall (7-Ply):

• Structure: Three medium layers

• Combinations: ACA, BAB, etc.

• Weight range: 600-1400 gsm

• Applications: Heavy industrial, pallets, crates

Flute-to-Flute (Xuegong Patent):

• Structure: Peak-to-peak corrugation

• 4-ply without core layer or 5-ply with core

• Benefits: Superior crush strength, no warping

• Patent holder: Xuegong Group

Choosing the Right Type:

Consider these factors:

• Product weight and fragility

• Stacking requirements

• Printing needs

• Cost constraints

• Environmental conditions

Flute Selection Guide:

| Need | Recommended Flute |

| Maximum cushioning | A or AC double |

| High print quality | E or F |

| General shipping | C or B |

| Heavy duty | BC double or triple |

| Thin profile | E or F |

Xuegong produces adhesives and equipment for all corrugated board types. Contact us for technical support.