What you need to know about boxes and packaging!
Types of corrugated boxing materials!
Corrugated fiberboard is comprised of outer linerboard and heavy paper medium or fluting.
Linerboard is the flat, outer surface that adheres to the medium. The medium is the wavy, fluted paper between the liners. Both are made of a special kind of heavy paper called containerboard.
Board strength will vary depending on the various linerboard and medium combinations.
FLUTE FACTS
Corrugated board can be created with several different flute profiles. Generally, larger flute profiles deliver greater vertical compression strength and cushioning. Smaller flute profiles provide enhanced structural and graphics capabilities for use in retail packaging.
![Fluting Types & Sizes](https://www.boxesandmore.co.za/wp-content/uploads/2021/06/fluting-types-size-boxesandmore.jpg)
The five most common flute profiles are:
A-Flute: On average 33 flutes per foot. Original corrugated flute design.
B-Flute: Approximately 47 flutes per foot and measures 1/8″or 3.175mm thick; perfect for canned goods.
C-Flute: Averages 39 flutes per foot and measures 5/32″or 3,968mm thick; common for shipping cartons.
E-Flute: Approximately 90 flutes per foot and measures 1/16″ or 1,5875mm thick, used for advertising displays.
F-Flute: About 125 flutes per foot and measures 1/32″ or 0,793mm thick; for small retail packaging.
Different flute profiles can be combined in one piece of combined board. For example, a triplewall board may contain one layer of A-flute medium with two layers of C-flute medium.
Mixing flute profiles allows designers to adjust compression strength, cushioning strength and total thickness of the combined board.
Terms you might encounter
- Adhesive: The substance used to hold plies of solid fiberboard together, to hold linerboard to the tips of flutes of corrugated medium, or to hold overlapping flaps together to form the joint or to close a box.
Basis Weight: An attribute of containerboard, but the values may be determined from the combined corrugated board. When determining the basis weight from combined board, the take-up factor of the corrugated medium, which varies with flute size, and the weight of the adhesive must be considered.
Bending: The ability of containerboard or combined board to be folded along score lines without rupture of the surface fibers to the point of seriously weakening the structure.
Blank or Box Blank: A flat sheet of corrugated board that has been cut, scored, and slotted, but not yet glued together.
Box Manufacturer: An establishment that has equipment to score, slot, print and join corrugated or solid fiberboard sheets into boxes, and that regularly uses that equipment in the production of fiberboard boxes in commercial quantities.
Box Style: Distinctive configuration of a box design, without regard to size. A name or number identifies styles in common use.
Boxboard: The types of paperboard used to manufacture folding cartons and set up (rigid) boxes.
- Carton: A folding box made from boxboard, used for consumer quantities of product. A carton is not recognized as a shipping container.
Compression Strength: A corrugated box’s resistance to uniformly applied external forces. Top-to-bottom compression strength is related to the load a container may encounter when stacked. End-to-end or side-to-side compression may also be of interest for particular applications.
Containerboard: The paperboard components (linerboard, corrugating material and chipboard) used to manufacture corrugated and solid fiberboard. The raw materials used to make containerboard may be virgin cellulose fiber, recycled fiber or a combination of both.
Corrugated Board, Corrugated Fiberboard: The structure formed by gluing one or more sheets of fluted corrugating medium to one or more flat facings of linerboard.
Die Cut: The act of cutting raw material (such as combined board) to a desired shape (such as a box blank) by using a die.
Dimensions: The three measurements of a box: length, width and depth. Inside dimensions are used to assure proper fit around a product. Outside dimensions are used in the carrier classifications and in determining pallet patterns.
Edge Crush Resistance/Short Column Compression (ECT): The amount of force needed to crush on-edge combined board is a primary factor in predicting the compression strength of the completed box. When using certain specifications in the carrier classifications, minimum edge crush values must be certified.
Facings: Sheets of linerboard used as the flat outer members of combined corrugated board. Sometimes called inside and outside liners.
Fiberboard: A general term describing combined paperboard (corrugated or solid) used to manufacture containers.
Flaps: Extension of the side wall panels that, when sealed, close the remaining openings of a box. Usually defined by one score-line and three edges.
Flute: The wavy layer of corrugated medium that is glued between the flat inner and outer sheets of linerboard to create corrugated board. Fluting generally runs parallel to the height of a shipping box.
Joint: The opposite edges of the blank glued, stapled, wire stitched, or taped together to form a box.
Kraft: German word meaning “strength”; designating pulp, paper or paperboard produced from wood fibers.
Panel: A “face” or “side” of a box.
Seam: The junction created by any free edge of a container flap or panel where it abuts or rests on another portion of the container and to which it may be fastened by tape, stitches or adhesive in the process of closing the container.
Stacking Strength: The maximum compressive load a container can bear over a given length of time, under given environmental/distribution conditions, without failing.
Tensile Strength: Indicates the containerboard’s resistance to breaking when it is pulled into or through equipment during the converting and printing processes.