TYPES OF CORRUGATED MATERIALS

Single Face Sheet

A corrugated medium with a linerboard facing adhered to one side. It can be manufactured in sheets or rolls. Single face is principally used as a wrapping material, and occasionally for interior packing or padding. 

Single Wall Corrugated

Single Wall Corrugated A corrugated medium with a linerboard facing adhered to both sides. It is also referred to as “Double Face”. This popular and versitile 3-ply construction is converted into a wide variety of containers and packaging components.

  • Most popular
  • Wide range of strengths

Double Wall Corrugated

Two corrugated mediums with a linerboard facing adhered between them and to both sides. This 5-ply construction is most applicable for packing heavy items where high rigidity and protection is required.

  • Made up of B and C Flutes
  • Extra padding and strength
  • Great for stacking heavy items

Triple Face Sheet

Three corrugated mediums and four linerboard facings. This 7-ply construction is used where large container sizes are involved, such as pallet packs.

  • Made up of B and C Flutes
  • Extra padding and strength
  • Great for stacking heavy items

Triple Wall Corrugated

Three corrugated mediums and four linerboard facings. This 7-ply construction is used where large container sizes are involved, such as pallet packs.

  • Made up of two layers of C Flute and one layer of B Flute
  • Very strong and crush resistant
  • Excellent for storage and transit

To vary the look of your corrugated box, you have the following choices in outside liner grades:

  • Kraft — Naturally brown in color. The most commonly used and least expensive liner.
  • #3 White — Mottled white, with underlying kraft showing through. Provides a cleaner look and better printability than kraft.t
  • #1 White — Bleached bright white. Offers very good printability, but easily soils during transit.
  • Premium Grades — Surfaces have a bright white clay coating, minimizing porosity so printing inks sit up on the surface. Gives excellent printability as colors are more vibrant and lower absorbency improves registration. However, because of the high hold-out, ink rub can be a problem
  • Litho-printed labels (for labels laminated onto corugated boxes).

Corrugated Flutes

The inventors of corrugated board applied the same principles to paper as ancient architects did to buildings. When trying to uphold heavy loads, the most efficient way is by using an arch. Generally the larger flute profiles give greater vertical strength and cushioning. The smaller flutes help enhance graphic capabilities while providing greater structural integrity. By experimenting with flute profiles, designers can vary compression strength, cushioning strength and thickness. Flutes come in several standard sizes such as A, B, C, E, and F. We currently convert all the above flutes in our facility. Different flute profiles can be combined in one piece of combined board. For instance, our doublewall board uses a B-C flute combination.

Standard US Corrugated Flutes

Flute Destination Flutes Per Linear foot Flutes Thickness (IN.) Flutes Cross Section
A Flute
33+3
3/16
B Flute
47+3
1/8
C Flute
39+3
5/32
D Flute
90+4
1/16

Other specialized flute size, includeing L, F and N, are less common but also available.
(Source: The Wiley Encoyclopedia in Packaging Technology)

TYPES AND DESCRIPTIONS OF FLUTES

The “Flute” describes the structure of the wave shaped cardboard material that makes up a board’s corrugation.

Flutes come in several sizes, known as flute profiles. The standard profiles range from A-flute (the largest) to F-flute and below (microflutes).

  • A-flute = 33 flutes/linear foot
  • B-flute = 47 flutes/linear foot
  • C-flute = 39 flutes/linear foot
  • E-flute = 90 flutes/linear foot
  • F-flute = 128 flutes/linear foot

Generally, larger flutes provide greater strength and cushioning, while smaller flutes have better 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 instance, CE double wall gets its durability from its C-flute layer, while the E-flute gives it a smoother printing surface.

A-Flute

A-Flute, the original flute, is the highest flute size, and therefore, when combined with an inner and outer facing, is the thickest. With 36 flutes to the foot, A-Flute makes the most of corrugated’s cushioning and stacking properties for fragile and delicate items. Because A-Flute offers excellent stiffness qualities and short column crush resistance, it has application across a broad range of customer uses.

  • 36 Flutes / Foot
  • 1/4″

B-Flute

B-Flute, the second flute size adopted by the corrugated industry, has lower arch heights than A and more flutes per foot (50). This means that the medium contacts and supports the liners at a greater number of points, providing a stiff, flat surface for high quality printing and die cutting and with excellent crush resistant properties. B-Flute is also preferred for high speed, automatic packing lines and for pads, dividers, partitions and other forms of inner packing. Complex die cuts and beverage trays are excellent applications for B-Flute as are can cases, wrap-around blanks, glass-to-glass packs and slipsheets. B-Flute is generally combined with light weight liners but can be used with heavier facings if the need arises.

  • 49 Flutes / Foot
  • Good puncture resistance
  • Less space consumed in warehouse
  • Uses: canned goods, displays

C-Flute

C-Flute came along next to split the difference between A and B Flutes. With 42 flutes per foot, it’s thinner than A-flute, thicker than B, and offers good cushioning, stacking and printing properties. C-Flute is by far the most widely used flute size. An estimated 80% of today’s corrugated containers are made of C-Flute board.

  • 41 Flutes / Foot
  • Good stacking strength
  • Good crushing resistance
  • Very common
  • Uses: glass, furniture, dairy

E-Flute

E-Flute has the greatest number of flutes per foot at 94 which gives it the greatest crush resistance and the flattest surface for high quality printing applications. The thin board profile of E-Flute (it is one-fourth the thickness of C-Flute) reduces box size and saves storage space. Because of its thin profile and excellent cushioning properties, E-Flute can often substitute for conventional folding cartons or solid fiber containers. Examples of E-Flute applications include boxes for cosmetics, fragile glass and ceramic items and delicate instruments. Another growing end-use is for pizza boxes where the retailer wants a cost effective container with good graphics and excellent product protection.

  • 95 Flutes / Foot
  • Light weight
  • Strong alternative to paper board
  • Superior printing surface
  • Excellent for custom die cut boxes
  • Uses: displays, point of purchase boxes

F-Flute

F-Flute, the newest flute, is just a little more than half the thickness of E-Flute and is the newest growth segment in the corrugated industry. The idea behind the new flute, originally developed in Europe, is to make packages with lower fibre content.

F-Flute, the newest flute, is just a little more than half the thickness of E-Flute and is the newest growth segment in the corrugated industry. The idea behind the new flute, originally developed in Europe, is to make packages with lower fibre content.

  • 128 Flutes / Foot
  • 1/32″

Corrugated Box Styles Overview

Over 90 percent of all goods in most developed countries are shipped in corrugated boxes. These boxes can be used for everything from apples to washing machines. By changing the design of corrugated boxes, combining layers of corrugated or adding interior packaging, a corrugated box can be manufactured to efficiently ship and store almost any product.Over 90 percent of all goods in most developed countries are shipped in corrugated boxes. These boxes can be used for everything from apples to washing machines. By changing the design of corrugated boxes, combining layers of corrugated or adding interior packaging, a corrugated box can be manufactured to efficiently ship and store almost any product.

The numerical code system, known as the International Fibreboard Case Code, was developed by the European Solid Fiberboard Case Manufacturer’s Association (ASSCO) to avoid confusion when communicating in different languages.

This code has been adopted by the International Corrugated Case Association (ICCA). Copies of the International Fibreboard Case Code are available from FEFCO.

There are many standard corrugated box styles- so many, in fact, that it is impossible to describe them all here. As you look through the following style descriptions, please keep in mind that there are other standard styles to choose from. In addition, corrugated boxes can be custom-designed to meet the specific needs of any box user. A manufacturers representative will have more information about additional box style options.

The following drawings are grouped into styles according to broad categories: Slotted Boxes, Telescope Boxes, Folders, Rigid Boxes (Bliss Boxes), Self-Erecting Boxes and Interior Forms.

Slotted Boxes: International Fiberboard Case Code: 02 Series

Slotted Box styles are generaly made from one piece of corrugated or solid fiberboard. The Blank is scored and slotted to permit folding. The box manufacturer forms a joint at the point where one side panel and one end panel are brought together. Boxes are then shipped flat to the user. When the box is needed, the box user squares up the box, inserts product and closes the flaps. The International Fibreboard Case Code refers to these styles as Slotted type Boxes, While carrier classifications call them Conventional Slotted Boxes.

0200 HALF SLOTTED CONTAINER (HSC)
Same as Regular Slotted Container without one set of flaps

0201 REGULAR SLOTTED CONTAINER (RSC)
All flaps have the same length, and the two outer flaps (normally the lengthwise flaps) are one-half the containers width, so that they meet at the center of the box when folded. If the product requires a flat, even bottom surface, or the protection of two full layers, a fill in pad can be placed between the two inner flaps.

This is a highly efficient design for many applications. There is very little manufacturing waste.

The RSC can be used for most products and is the most common box style.

0202 OVERLAP SLOTTED CONTAINER (OSC)
All flaps have the same length. The outer flaps overlap by one inch or more.

This style is especially resistant to rough handling. Stacked on its bottom panel, the overlapping flaps provide added cushioning. Stacked on its side, the extra thickness provides stacking strength.

0203 FULL OVERLAP SLOTTED CONTAINER (FOL)
All flaps have the same length (the width of the box). When closed, the outer flaps comes within one inch of complete overlap.

This style is especially resistant to rough handling. Stacked on its bottom panel, the overlapping flaps provide added cushioning. Stacked on its side, the extra thickness provides stacking strength.

0204 CENTER SPECIAL SLOTTED CONTAINER (CSSC)
Inner and outer flaps are cut to different lengths. Both pairs of flaps meet at the center of the box.

The style is especially strong because both the top and bottom have double the thickness of corrugated board. The inner flaps with no gap, provide a level base for the product.

A variation of this box is the Side Special Slotted Container – SSS. All pairs of flaps meet, but not at the center of the box.

0205 CENTER SPECIAL OVERLAP SLOTTED CONTAINER (CSO)
All flaps have the same length (one-half the length of the box). The length of the box can be no more than twice its width.

When closed, the inner flaps meet at the center of the box, providing a level base and full top protection. Depending on the ratio of length to width, the outer flaps overlap at random, up to full overlap.

CENTER SPECIAL FULL OVERLAP SLOTTED CONTAINER (SFF)
Inner and outer flaps are cut to different lengths. When closed, the inner flaps meet at the center of the box, and outer flaps fully overlap.

With three full layers of combined board over the entire top and bottom, this style provides extra cushioning when stacked on its bottom, or extra stacking strength when stacked on its side.

0215 SNAP 0R 1-2-3 BOTTOM CONTAINER WITH TUCK TOP
The four flaps the form the bottom panel are die cut. To set up, the user folds the largest bottom panel first, then the two end panel is folded and pressure is applied near the center, the flap “snaps” into the slot created by the other panels.

The style is convenient for small-volume shippers who do not have automatic set up equipment. Because the bottom is not fully sealed, it may not be suitable for heavy products.

0216 SNAP OR 1-2-3 BOTTOM CONTAINERS WITH RSC TOP
Same as 0215, replacing the tuck top configuration with RSC style Flaps.

0225 FULL BOTTOM FILE BOX, HAMPER STYLE, FT. WAYNE BOTTOM, OR ANDERSON LOCK BOTTOM
When set up, this box provides an interlocking thickness on its bottom and on its end panels

0226 BELLOWS STYLE TOP AND BOTTOM CONTAINER

Telescope Boxes: International Fiberboard Case Code: 03 Series

Telescope boxes usually consist of a separate top, or top and bottom, that fit over each other or a separate body. The International Fiberboard Case Code calls these boxes Telescope-Style. The truck and rail classification call them Telescope Boxes if the cover extends over at least two-thirds of the depth, and Boxes with Covers if the cover extends over less than two-thirds of the depth.

0301 “SS” SIDE SLOTTED
0301 “ES” END SLOTTED

0301 FULL TELESCOPE DESIGN STYLE CONTAINER (FTD)
The two-piece box is made from two scored and slotted blanks (trays)

0310 DESIGN STYLE CONTAINER WITH COVER (DSC)
A tube forms the body. The two interchangeable covers are usually design style. The pieces are shipped flat to the user, who opens the tube and sets up the covers.

This style is frequently used for tall or heavy products that would be difficult to lower into a box. The item is placed on the bottom cover, and the tube is lowered over the product.

0320 FULL TELESCOPE HALF SLOTTED CONTAINER (FTHS)
The two-piece box is made from two half slotted containers.

0325 INTERLOCKING DOUBLE COVER CONTAINER (IC)
Flanges on the body, folded together (interlocked/baseloid) with flanges on the covers, are held in place with strapping.

The style offers the same ease of packing provided by the double-cover box, with the assurance that the covers will not separate from the body.

This feature is advantageous for moving large or heavy products such as washers, dryers, refrigerators, water heaters, vending machines and some hazardous materials.

0351 OCTAGONAL DOUBLE COVER CONTAINER
Same as 0310 with additional panels.

Folders: International Fiberboard Case Code: 04 Series

For folders, one or more pieces of combined board provide an unbroken bottom surface, and are scored to fold around a product. The International Fiberboard Case Code describes them as Folder-Type Boxes. The carrier classification uses the term Folders.

0401 ONE PIECE FOLDER (OPF)
One piece of board is cut so that it provides a flat bottom, with flaps forming the sides and ends, and extensions of the side flaps meeting to form the top.

0403 ONE PIECE FOLDER WITH AIR CELL/END BUFFERS, PROTECT ALL OR BOOK WRAP

0406 WRAP AROUND BLANK
A wrap-around blank is formed blank into a box by folding it tightly around a rigid product. The positioning of the product, folding and sealing are performed by automatic equipment.

The finished box is essentially an RSC, turned on its side so that the bottom and top are unbroken. The joint, however, is not formed until the final closure.

0410 FIVE PANEL FOLDER (FPF) OR HARNESS STYLE FIVE PANEL FOLDER
A tube forms the body. The two interchangeable covers are usually design style. The pieces are shipped flat to the user, who opens the tube and sets up the covers.

This style is frequently used for tall or heavy products that would be difficult to lower into a box. The item is placed on the bottom cover, and the tube is lowered over the product.

0411 CENTER SEAM (FPF)

0415 ONE PIECE FOLDER (OPF) WITH DUST FLAPS

0416 ONE PIECE FOLDER (OPF) DIE CUT WITH DUST AND TUCK FLAPS

0422 ROLL END TRAY, WALKER LOCK TRAY OR TRAY WITH SELF LOCKING ENDS
Formed from a single piece of combined board, the design features an unbroken, and several; layers of corrugated in the end panels.

Trays are not shipping containers, but they are frequently used as inner containers for parts, delicate produce, letter mail and other products, or as elements of display stands.

0427 ROLL TRAY WITH LOCKING COVER

0457 SELF LOCKING TRAY, JOINT LESS TRAY

0460 DISPLAY TRAY OR HIGH WALL TRAY

0470 ROLL END TRAY WITH TUCK TOP AND INTERIOR BOTTOM FLAPS OR REVERSE WALKER LOCK WITH INSIDE TUCK TOP
Rigid Boxes (Bliss Boxes): International Fiberboard Case Code: 06 Series

0601A BLISS STYLE CONTAINER WITH END FLAPS

0601B BLISS STYLE CONTAINER WITH END FLAPS AND END PANEL LEGS

0606A BLISS STYLE CONTAINER
0606B BLISS STYLE CONTAINER WITH END PANEL LEGS

0606B Bliss Style Container With End Panel Legs

0711 PRE-GLUED AUTO BOTTOM WITH RSC TOP FLAPS
The top panels of the box are usually those of a regular slotted container.

For a telescope-style box, two self-erecting pieces can be used. (International Fibreboard Case Code 0714).

0760 SELF ERECTING SIX CORNER TRAY
Interior Forms: International Fibreboard Case Code: 09 Series
Liners, tubes, pads, build-ups, dividers, partitions and other inner pieces can be made in an infinite variety of ways to separate or cushion products, to strengthen the box or to prevent product movement by filling voids. This may be simple rectangles, or scored, slotted, scored and slotted, or die cut shapes. Many of the common interior forms have been given International Fibreboard Case Code numbers. The carrier classifications provide specifications for some pieces used in the packing of glassware and other fragile articles.

0900 PADS
Pads are plain shapes of corrugated or solid fiberboard. They can be used to fill the space between the inner flaps of an RSC, to completely cover the bottom or top of a box, or to separate layers of product. Vertically, they can be used to separate products.

Tubes are scored rectangles, folded and sometimes joined with tape to form a multisided structure open at both ends. When used as sleeves for individual items such as glassware, adjacent shell provide double protection.

PARTITIONS
Partitions or divides provide a separate cell for each item in a box. They are used primarily for glassware and other fragile articles.

Scored and a folded inner packing pieces can take many shapes. Included in this group are built-up pads consisting of multiple pieces glued together. Inner packing pieces are used for cushioning, suspension and separation, and to fill voids. The suspension function holds the product away from the walls of the box to lessen the impact of drops or bumps. Completely filling the voids created by irregularly shaped products adds strength to the box.

Inner Packing Forms are usually die cut to position and support irregular products form below, or lock them into position from above. Alternatively, forms can be place on two sides or ends of a product. Some inner packing forms are extensions of the box flaps.

Bulk Bins

The bulk bin is a large corrugated fiberboard tube of half-slotted body, with one or two covers, frequently of the interlocking type.

The distinction between a box and a bulk bin is not defined in the box style itself, but usually refers to the quantity of the contents. The container for 40 pounds of a granular product, or a single refrigerator, is a box; the container for 3000 pounds of a granular product (“in bulk”), or 500 Towels (“loose” products) or small packages is a bulk box.

Some carriers encourage the use of bulk bins to consolidate smaller packages and reduce handling time. However, the customer must be capable of handling the bulk at its ultimate destination.

Because of their filled weigh, bulk bins are frequently placed on a pallet, providing easy access for the tines of a forklift truck. Lift trucks with special attachments (baseloid) are sometimes used; the attachments slip under the flanges of the interlocking covers and pallets are not needed.

Bulk bins are used for everything from automobile parts to marshmallows.

BOX DIMENSIONS

Dimensions are given in the sequence of length, width and depth. Internationally, the words length, breadth and height may be used to express these dimensions. The dimensions of a box are described based on the opening of an assembled box, which can be located on the top or the side, depending on how it is to be filled. The opening of a box is a rectangle; that is, it has two sets of parallel sides. The longer of the two sides is considered its length, the shorter of the two sides is considered its width. The side perpendicular to length and width is considered the depth of the box.

Dimensions can be specified for either the inside or the outside of the box. Accurate inside dimensions must be determined to ensure the proper fit for the product being shipped or stored. At the same time, palletizing and distributing the boxes depends on the outside dimensions. The box manufacturer should be informed as to which dimension is most important to the customer.

Corrugated is the ultimate in flexible packaging material. Ninety (90) percent of all goods shipped to market are packaged in corrugated. There are many standard styles (some listed below) and there is also an unending array of custom designed packaging products.Box makers normally prefer dimensions of a box to be expressed as inside dimensions. It is very important to be precise in giving us the three dimensions accurately.

METHODS OF BOX CLOSURE

Stapling: An effective method of box closure

There are four main ways to close a corrugated box: Taping, stapling, strapping and gluing. In this article, we will focus on the use of staples in corrugated carton closure. What are some of the benefits of stapling over the other methods of box closure, you ask? Well, for starters, stapling is:

Cost effective
The more cartons you close, the more you’ll save by stapling. Strapping and taping can be up to 50% more expensive in terms of material and labour costs. Furthermore, many packaging designs can be simplified to use less material when staples are used for closing – and less material means lower packaging costs.

Strong, stable and secure
Stapling is ideal for packaging heavy items and for long distance shipping. They also hold well in all weather and environmental conditions. A stapled box is always a safe package, whether damp, dusty, hot or cold.

Attractive and “pilfer-proof”
A stapled box leaves a clear, unmarred surface; no part of the box is obscured (especially print) and the box achieves its function as a messenger. And because a stapled box is difficult to re-close, the staples act as a deterrent to the thief. Traces of the crime are obvious; thus a break-in during transport can be detected before the package reaches the customer.

Environmentally friendly and efficient
Staples are 100% natural and recyclable. They are also compact, requiring only 1/40 of the space needed by tape.

The best way to staple corrugated cartons

The following illustrations show the most efficient method of stapling the tops and bottoms of corrugated boxes. Note that the number of staples required in each case depends on several factors, including board quality and test, contents, staple type etc.

Packaging Tape: A sticky business

A very common question asked by many of our customers that use packaging tape is “What is the difference between PVC and Polypropylene packaging tapes?” …which is usually followed by “Which kind of packaging tape should I be using?”

PVC (polyvinylchloride) and Polypropylene are the base materials used to make a packaging tape’s backing.

Adhesives – Natural rubber, acrylic or Hot Melt – are then applied to the PVC or Polypropylene backing to provide the ‘sticking’ power.

In general, most people find that PVC packaging tape is superior to Polypropylene in every area except price and recyclability. Don’t worry – both tapes work well in most situations. As a general rule, however, you should use PVC for quality and Polypropylene for economy.

To help our customers decide which packaging tape makes the most sense for them, we provide this list of packaging tape ‘adhesive’ performance criteria and which packaging tapes perform good, better, and best against each criteria.

Resistance to yellowingNRBestBetter

Adhesive Performance Natural Rubber Acrylic Hot Melt

PVC Backing

Polypropylene Backing
Overall Performance
Best
Better
Good
On over-stuffed cartons
Better
Good
Best
On printed/coloured cartons
Best
Better
Good
On rough/recycled cartons
Best
Better
Good
On poly film/wrap
Best
NR
Better
Resistance to dampness
Best
NR
Better
Overall calrity
Good
Better
Good
In cold temperatures
Best
Better
NR
In hot temperatures
Best
Better
NR
Application temperatures
32-150F
32-150F
45-120F
Service temperatures
-40-170F
-10-150F
-10-140F

NR = not recommended for this application

Both PVC and Polypropylene packaging tapes are printed and are available in various colors. PVC tapes have a smoother, quieter ‘unwind’. Polypropylene packaging tape with an acrylic adhesive is more environmentally friendly because the adhesive is water-based.

STORING AND HANDLING BOXES

How to store and handle corrugated boxes

Box users make major investments in the development, production and promotion of their products. The boxes they need for shipment represent, on average, less than 1% of the value of their contents. Consequently, if a few boxes are unusable, the loss involved is relatively insignificant, right? Wrong! Remember, without the lowly corrugated box, the product can not be shipped! Simply stated, unusable boxes can result in unsold products. Therefore, it is worth protecting your inventory of empty corrugated boxes to ensure that:

  • The boxes are usable, and don’t end up ready for recycling before they can fulfill their purpose;
  • The boxes will run smoothly on automatic setup, filling and closing equipment, avoiding costly jam-ups, repacking and lost time;
  • The boxes will stack squarely, avoiding costly accidents during palletization, storage and shipment;
  • The boxes provide the intended protection against damage, leakage or other loss.

Guidelines for proper handling and storage of empty boxes, developed by the Fibre Box Association and the Packaging Machinery Manufacturers Institute, have been summarized and presented below. Following these simple guidelines will maximize the performance and prolong the useful life of your corrugated boxes:

Position

1. Store boxes flat from the time they are received until they are ready for use.

Damage to the edges of boxes can occur if they are stored on edge, which can affect runnability on automatic equipment, closure and product protection.

Stability in Storage

2. Leave the strapping, bundling or other unitizing device in place until boxes are ready for use.

3. Alternate bundle direction, or alternate loose boxes at intervals for greater stability.

4. Avoid stacking boxes too high, whether loose or banded, because of slight instability of stack.

Although close, most box styles are not totally flat. The extra thickness of the tab used at the joint adds a bulge, usually near the centre, giving a tilt to a loose stack of boxes. Alternating directions of bundles when stacking compensates for the tilt and increases stability.

Crushing & Puncture

5. When building pallet loads of flat boxes, use deck boards to distribute weight evenly.

6. Stack boxes only on smooth, clean surfaces.

7. Use good materials handling procedures; don’t drop or throw bundles or pallet loads into place.

8. Don’t stand, sit or climb on stacked boxes, or place other heavy objects on them.

This may crush or distort the flutes in corrugated boxes which will reduce their protective abilities. Any uneven pressure on the flutes can cause crushing or puncture.

Storage Environment

9. Store boxes off the floor, on pallets or other flat dunnage.

10. Store boxes indoors and protect them from overhead moisture.

This may require covering boxes or storing them away from overhead pipes or areas of ceiling condensations.

11. Avoid temperature and humidity extremes and fluctuations in storage areas.

This may require storage away from doorways that are opened frequently. When it is impossible to avoid extremes or fluctuations, bring the boxes to the packing line or another area for a period of time to condition them to a more normal atmosphere before using them. Excessive moisture or water can soften or dissolve the corrugating adhesive, causing delamination; a box that literally falls apart won’t offer much protection. Heat can reduce the moisture content of corrugated boxes, making them brittle. Extreme cold also affects moisture content, making the boxes more fragile.

Old Age

12. Follow “first in, first out” practices in using inventory.

Corrugated boxes stored under ideal conditions will remain usable for a long period of time. Less-than-ideal or fluctuating conditions reduce their effectiveness and shorten their useful life. Common sense dictates that old inventory be used before starting on the new.

The preceding information and illustrations on how to store and handle corrugated boxes are from the Fibre Box Handbook (Fibre Box Association, Rolling Meadows, IL, 1992)

CONVERSION CHARTS

Minimum Bursting Test, Singlewall, Doublewall (lbs. per sq. in) Minimum Edge Crush Test (ECT) (lbs. per in. width) Minimum Combined Weight of Facings, Including Center Facing(s) of Doublewall Maximum Weight of Box and Contents (lbs.) Maximum Outside Dimensions, Length, Width, and Depth Added (inches)

Singlewall
125
23
52
20
40
150
26
66
35
50
175
29
75
50
60
200
32
74
65
75
250
40
111
85
85
275
44
138
95
95
350
55
180
120
105

Doublewall
200
42
92
80
95
275
48
110
100
95
350
51
126
120
105
400
61
180
140
110
500
71
222
160
115
600
82
270
180
120

E Flute
150
26
66
35
50
200
32
84
50
60

F Flute
150
26
66
35
50
200
32
84
50
60