Corrugated Packaging Glossary: 50 Essential Terms

Understanding industry terminology is essential for effective communication with suppliers, customers, and equipment manufacturers. Here are 50 key terms.

Board Components

Liner: The flat facing sheets on the outside of corrugated board

Medium (Fluting): The wavy corrugated paper between liners

Single-Face: One liner glued to corrugated medium

Single-Wall: Fluted medium between two liners (3-ply)

Double-Wall: Two mediums with three liners (5 or 7-ply)

Flute Types

A-Flute: Largest flute, ~4.8mm, excellent cushioning

B-Flute: ~3.0mm, good crush resistance

C-Flute: ~4.0mm, most common profile

E-Flute: ~1.5mm, excellent print surface

F-Flute: ~0.8mm, thinnest standard flute

Production Equipment

Single Facer: Makes single-face corrugated

Double Backer: Bonds liner to single-face web

Bridge: Accumulates single-face web between stations

Hot Plates: Heat the board during double backer bonding

Slitter-Scorer: Cuts and scores board to width

Cut-Off: Cuts board to length

Quality Measurements

ECT (Edge Crush Test): Measures stacking strength

FCT (Flat Crush Test): Measures cushioning

BCT (Box Compression Test): Measures box strength

Cobb Test: Measures water absorption

Caliper: Board thickness

Adhesive Terms

Gel Temperature: Temperature at which starch gelatinizes

Viscosity: Adhesive flow resistance (Stein-Hall seconds)

Carrier: Pre-cooked starch that suspends raw starch

Tack: Adhesive stickiness

Open Time: Time adhesive remains workable

Production Terms

MSF: Thousand Square Feet (production unit)

Web: Continuous sheet of paper or board

Warp: Board curling or twisting

Wash Boarding: Visible flute pattern on liner

Delamination: Separation of board layers

This glossary covers English terms commonly used internationally. Local markets may use different terminology.