GLOSSARY OF TERMS

Corrugating Material or Corrugating Medium: Paperboard used in forming the fluted portion of the corrugated board.

Linerboard: Paperboard used for the flat facings in corrugated linerboard.

Facings: A form of linerboard used as the flat members of corrugated fiberboard.

Corrugator: A machine which takes container board from three rolls and combines it into a corrugated board consisting of two exterior facings and an intermediate fluted member. The corrugator forms the intermediate material into a series of arched trusses and attaches the facings to them with adhesive applied at the tips of the flutes. The resulting board is called single wall corrugated fiberboard. By taking containerboard from five rolls, it also produces a corrugated board, commonly known as double wall, consisting of three facings and two corrugated mediums. By adding another corrugated medium and facing, triple wall corrugated fiberboard is produced. The machine also cuts the fiberboard to size and may score it in one direction.

Single Face Corrugated Board: The structure formed by one corrugated member glued to one flat facing.

Single Wall Corrugated Board: Also known as Double Face. The structure formed by one corrugated inner member glued between two flat facings.

Double Wall Corrugated Board: The structure formed by three flat facings and two intermediate corrugated members.

Triple Wall Corrugated Board: The structure formed by four flat facings and three intermediate corrugated members.

Heavy Duty: Same set up as single wall, but the liner board is heavier.

Score: An impressions or crease in corrugated or solid fiberboard to locate and facilitate folding.

Slot: A cut made in the fiberboard sheet, usually to form flaps and thus permit folding. Widths of one fourth and three eighths inch are common.

Slit: A cut made in fiberboard sheet without removal of material.

FOL: Flaps of full overlap slotted containers (FOL) are all the same length. Outer flaps overlap not less than inside width of box minus a maximum of 1 inch. This style is especially resistant to rough handling and is an excellent option for an end-loaded carton.

RSC: Regular slotted container. All flaps are the same length, and lengthwise flaps meet at the center of the box. RSC boxes are in more general use than any other style because they are economical to manufacture and use.

OSC: Overlap Slotted Container. All flaps are the same depth; the outer laps overlap by 1" or more.

Five Panel Folders: End flat construction and tuck are specified on FPF. When assembled, have several thicknesses of fiberboard in each end. The FPF has a particular advantage when used for packing long articles of small diameter which might be damaged if forced through ends of the container.

Die cut: A cut made with special steel rule dies. The act of making a part or container which is cut and scored to shape by such tools. Also used to denote a board which has been die cut.

Liner Board and Paper Fibers: The main component of corrugated is liner board. Liner board is made up of compacted pulp paper fibers of varying lengths. Virgin pulp fibers are longer and, as a result, stronger than the shorter fibers of recycled paper. Liner board with a high recycled content will tend to be structurally weaker than liner made from virgin pulp.

Mullen Test and Edge Crush Test (ECT): The original, historic measurement for corrugated boxes was the Mullen Test. This test was performed by taking a 1”x1” steel rod and poking it through a sheet of corrugated. The amount of weight required to push the rod through the sheet indicates the board measurement. The most common box strength of shipping containers is 200lb. The Edge Crush Test (ECT) was developed as a better measurement of a box’s strength, since it measured the weight required to crush the vertical edge of a box, where it’s strength is more important. ECT also allowed for great variability in the liner board combinations while still ensuring the box’s comparative strength.