In this guide, we will introduce the definition, use, benefits, and other knowledge of corrugated boxes in detail. Read on for more information.

1. What is a Corrugated Box?

A corrugated box is a disposable container whose sides are made up of layers of material that include an inside layer, outer layer, and middle layer. The middle layer is fluted, which means it is styled in rigid, wave-shaped arches that provide cushioning and support for weighted materials placed in a corrugated box.

The common cardboard box has been around for over 200 years. The practice of adding flutes for corrugation began in the middle of the first industrial revolution. Over the years since its development, the corrugated box has become the most common form of shipping container and is found in every aspect of material management and transport.

Corrugated Box

2. How Corrugated Boxes are Made

Though the construction of a corrugated box may seem to be a simple and easy process, various elements have to be considered prior to beginning manufacturing. As with all manufacturing and shipping equipment, corrugated boxes are designed and engineered to determine what they can hold, how much, and their strength.

The first step in box manufacturing is to examine the various elements of the box, which are construction, flute size, burst strength, edge crush strength, flat crush strength, the heaviness of the cardboard sheets, the weight of the paper, and types of surface treatments.

1) The Important Elements of a Corrugated Box

The following are elements of a corrugated box.

#1. Corrugated Box Construction

There are three types of walls for a corrugated box: single, double, or triple.

  • Single Wall – This is the simplest corrugated wall design, with a single outer layer and inner layer with fluting between the two layers.
  • Double Wall – The double wall design adds an additional layer of fluting to produce a box capable of handling heavier and larger items.
  • Triple Wall – As the name implies, triple wall corrugated boxes have three layers of flutes. Each layer has differently-sized flutes to add stability. The added layers maximize cushioning and compression strength.

Corrugated Box

#2. Corrugated Flutes

There are five common types of corrugated flutings, which are A, B, C, E, and F. Though these are standard, manufacturers and designers can create and construct customized versions, which can be combinations of the standard versions or unique, unusual designs.

  • A – is the original type of flute at 36 flutes per foot and is used for double wall applications and thick corrugated padding.
  • B – has the second highest arch size with 49 flutes per foot and has stacking strength and crush resistance.
  • C – most commonly used flute with 41 flutes per foot for cushioning, stacking, and printing properties.
  • E – second common flute, environmentally friendly with 90 flutes per foot.
  • F – has small, tighter flutes, and is environmentally friendly with 128 flutes per foot.

Aside from the five above flute styles, there are specialty flutes that are combinations of the above flutes or that fall between the regularly used flutes, such as D flutes. Other special flutes include EE, EF, and BC, which are used with double-wall flute profiles. Flutes such as N and O are rarely used and are extremely small at less than half a millimeter.

#3. Mullen Test (Burst Strength)

The burst strength of a corrugated box refers to the amount of force that can be applied before the material ruptures, cracks, or falls apart. The Mullen Test, which was developed over 130 years ago, applies force to the face of the corrugated material until it bursts. The results of the test are given in pounds with a rating. For example, a box rated at 200# can withstand 200 pounds (90 kg) of force per square inch. The results of the Mullen test offer data regarding the amount of force per square inch required to burst through the paper on a corrugated box.

The Mullen test is an indicator of how a box will endure its treatment when it is being shipped individually and subjected to the rough handling of assembly operations and mail carriers. As it moves through the multiple distribution channels, the contents of the box are more likely to move inside and possibly cause a puncture.

The flaw with the Mullen test is that the fluted medium doesn’t add to the bursting strength of the box. This isn’t to say the medium isn’t important because 50% of the stacking strength of a box comes from the medium. This is where the Edge Crush Test comes in.

#4. Edge Crush Test (ECT)

The ECT test measures the vertical compression strength of a box and serves as an indicator as to how well a box will react to being stacked for shipping or placed on a pallet. It is a sensible and reliable test to determine how well a box will hold its form during transit and while being handled. The ECT test is a “performance-based” property test rather than a “material characteristics” test.

The ECT of a box can be influenced by several factors, which include humidity, the amount of time a box remains stacked, the number of crushes from going through a production machine, and the stacking pattern. A box that tests with an ECT of 55 will be able to withstand 55 lbs (25 kg) of pressure.

Corrugated Box

#5. Basis Weight

The basis weight is a measurement of the weight of cardboard sheets before being made into boxes and is the weight, in pounds, of a ream of paper. Since paper comes in different sizes and widths, the basis weight can vary and must be calculated by measuring and weighing a piece of paper.

#6. Paper Weight

The weight of cardboard is dependent on how thick the cardboard paper is. The weight of the paper to make the sheets of corrugation is measured in pounds, which can vary from 26 lbs. to 42 lbs (11.8 to 19 kg).

#7. Coatings

During the production of corrugated boxes, coatings, and finishes are applied to protect the stability of the box and give it a certain appearance. There are two basic types of coatings, which are aqueous and UV.

  • Aqueous – Aqueous is a clear fast-drying coating that serves as protection for the surface of a box. It can be high gloss or matt and protects against wear and dirt.
  • Ultraviolet (UV) – Ultraviolet is cured under ultraviolet light and is resistant to scratches and scuffs. It is more expensive than aqueous coating but lasts longer and is sturdier.

2) How Corrugated Boxes are Made

The following are about how the corrugated boxes are made.

#1. Producing Corrugated Board

The machine that produces the corrugated board for corrugated boxes is called a corrugated box machine. The main elements of a corrugated board are liners that are flat-facing of the board and come from various grades of paper. This central element is made from the long fibers of softwood trees. The fluted portion is made from shorter fibers found in hardwood trees.

Huge rolls of paper are combined in a single facer that produces the fluted form. To create the flute, the paper is steam heated to 338 ° F (170° C). The fluted paper is attached to a single sheet of the liner by the application of glue at a controlled temperature to the peaks of the flutes and pressed flat by pressure rollers. This produces the single-faced web.

The single-faced web leaves the single facer and moves on to the double glue unit and double backer. To produce a double wall corrugated paper, two single-face webs are fed into the unit as well as the liner. In the double glue unit, the exposed flute tips have glue applied to connect the outside liner. During the process, the liner and fluted single-face web are constantly heated at controlled and monitored temperatures to cure the glue and ensure a secure bond.

After leaving the double backer, the corrugated board is pulled through the dryer, scored, and cut to the required lengths.

The various lengths of the board are stacked to be fed into the box printing and creation equipment. Depending on the type of boxes, they are printed with logos, designs, and an assortment of colors.

Corrugated Box

2) Finalizing Corrugated Boxes

The scored, printed, and cut corrugated boards are fed into a trimmer that perforates the boards to create flaps and handles. This process can complete as many as 90 boxes per minute.

Once the boxes have been sufficiently formed and trimmed, they are sent on to the folding machine that bends the box along the score lines and applies glue to the sections that will be joined together to complete the forming of the box.

3. Uses for Corrugated Boxes

What we consider to be the common shipping box is one of the most used shipping tools available to manufacturers for use in shipping their products. Since corrugated boxes can be designed and produced to fit nearly every shipping need, they are one of the most omnipresent and accessible logistical devices.

Corrugated boxes are famous for their structural rigidity and protective cushioning for shipping fragile and delicate items. There are countless advantages to using corrugated boxes that can be customized to fit any type of shipping need.

An important reason that corrugated boxes are used by industry is the ability of box manufacturers to print on the boxes and place a company‘s logo. A clean image of a company‘s logo goes a long way to promoting its brand and making it recognizable. Boxes are an inexpensive way of making a company‘s image unique and distinct.

1) Uses for Corrugated Boxes

The following is about the use of corrugated boxes in various fields.

#1. Food Industry

In the manufacturing process of corrugated boxes, the glue used to connect the flutes and liners is made from water and starch to avoid contaminating fresh fruits and vegetables. There are many benefits to using corrugated boxes for shipping food. The most important of the benefits is their safety and resistance to bacterial infection. Various research studies have shown that corrugated boxes keep food fresher longer.

Corrugated Box machine

#2. Office Supply and Stationary

The main concern when shipping or storing office supplies, especially paper, is the possibility of supplies being damaged in transit or while sitting on a shelf. The strength and cushioning of corrugated boxes prevent this from happening and remove the worry of having damaged work materials.

#3. E-Commerce

In the e-commerce industry, boxes serve multiple purposes, the most important of which is an efficient and highly responsive supply chain, a critical part of e-commerce. Corrugated boxes are the backbone of the e-commerce supply change and have been growing in use over the last two years. A challenge for the e-commerce industry is the shipment of smaller quantities to a growing number of unique and unusual destinations. Corrugated boxes offer the type of security and safety that the e-commerce industry demands.

#4. Textiles

Online shopping has led to a rapid rise in the use of boxes for the shipment of textiles. Billions of dollars are being invested in shipping materials that will guarantee safe, reliable, and damage-free delivery. Since customer satisfaction is the key to maintaining and keeping customers, corrugated boxes have become a significant part of the planning for meeting customer demands.

It is estimated that over 50% of customers will return to a company if the textiles they receive are packaged properly. Corrugated boxes make it possible for textile manufacturers to personalize boxes to fit the product and the customer, which ensures repeat customers.

#5. Electronics

Great care has to be taken when choosing boxes for the shipping of electronics and electronic components. These types of items are fragile and can be damaged easily by not being packed correctly. For this reason, corrugated boxes are used and supplemented with packing materials for added protection. The greatest concern is the amount of stress placed on components in the handling of the box. The shock from such stress can damage a circuit or loosen a connection. The cushioning found in a corrugated box alleviates worry and prevents damage, ensuring that an electronic product arrives on time in perfect condition.

#6. Healthcare

Much like the needs of the electronics industry, materials shipped for healthcare needs require the same type of care and concern. Delicate and sensitive medical instruments can be easily damaged by poor packaging and mishandling. In the case of medications, there are several requirements regarding shipping conditions to ensure that they arrive safely. The wide assortment and selection of corrugated boxes make it possible for pharmaceutical companies to ship their products with confidence, knowing that medications are well-protected and safe.

#7. Batteries

Shipping materials for the battery industry have to meet strict guidelines and regulations for safety and legal compliance. The fiberboard used to produce these specially designed boxes follows the established guidelines of the corrugated box industry. Aside from the use of specially produced liners, each battery shipping container has to be clearly marked regarding the contents with appropriate safety guidelines.

Corrugated Box machine

#8. Automotive

The shipping of auto parts requires careful preparation since they come in a wide variety of sizes and shapes. The basic rule is to protect the part to be shipped from harm by providing packing material that is sturdy, able to handle weight, and cushioned.

The choice of container is highly dependent on the parts to be shipped, which can vary from lug nuts to carburetors. Large parts need a box that won‘t burst or be destroyed by handling. Box manufacturers and part suppliers have charts that offer guidance regarding what type of box to use for certain parts.

#9. Military

When supplying shipping materials for the military, there are several Mil-Spec regulations that must be followed. Unlike other industrial applications, the military provides a list of requirements and a description of production methods for producing materials for their use. The first and most obvious requirement for military boxes is that they be sturdy.

Aside from being strong and sturdy, corrugated boxes must be designed to withstand a variety of climatic conditions, which include high humidity, extreme temperature changes, and wet environments. The function of military shipping materials is to offer maximum protection for sensitive and technical instruments, as well as meet American Society for Testing and Materials (ASTM) standard D5118.

#10. Publishing

For publishing companies, the shipping of books, documents, magazines, and other printed material has the major problem of weight since a large amount of printed material can be significantly heavy. Once the problem of weight is resolved, the next concern is moisture, which can severely damage printed matter.

Though the exterior of corrugated boxes is coated with protective finishes, it is important to line the interior of the box with plastic or some form of wrapping material as an extra layer of protection from moisture. The most obvious solution is to use boxes that have a triple thickness of fiberboard.

Corrugated Box

4. Benefits of Using Corrugated Boxes

After careful study of corrugated boxes, it is easy to see how valuable they are as a shipping tool. Their main advantage is their strength and durability, even though they are made of molded paperboard and glue. Each type of box is designed to perform under a wide variety of conditions, from places where it rains constantly to extreme heat. This flexibility is the reason that corrugated boxes are an essential part of world shipping.

1) Protective against Outside Elements

The productive strength of corrugated boxes includes their ability to keep moisture and bacteria out. They serve as a stable cushion and come in sizes that can vary according to the items to be shipped.

Corrugated boxes keep products safe during long-distance transportation, shipping, and handling. The type of corrugated protection can be adjusted for fragile and delicate items using varied thicknesses and sizes.

The wavy fluted medium provides a lightweight layer of protection. Corrugated fiberboard offers excellent protection against the elements as well as the wear and tear of shipping. The lightweight corrugated fiberboard makes it a better shipping material than wood or plastic. It’s also far less expensive and easier to recycle, making it better for the environment and pocketbook.

2) Customizable to Demands

Though there are standard shapes and sizes of corrugated boxes, they can easily be manufactured to fit any type of circumstance and demand. An additional part of their customization is the ability to have their sides or top and bottom printed with company logos and designs.

Coatings, treatments, different adhesives, and flame resistance can all be applied. Corrugated boxes come in all sizes to be easily folded into different shapes to make a perfect fit.

High-quality custom designs make a product recognizable. Good quality shipping materials reinforce the values of a company‘s operation and the power of its brand. By having a well-engineered and creative display on a corrugated box, a company creates a stronger, lasting brand identity.

3) Cost-effective and Reusable

The main reason that corrugated boxes have become so widely used is their cost compared to other forms of containers. Their use does not require increased labor, expensive tooling, or specialized equipment. Once they have met their usefulness, the corrugated fiberboard can be returned for recycling and remanufacturing.

4) Compatible with Branding

Every company is constantly devising methods to make their image and name known. One of the least expensive methods for achieving this goal is by placing the name and brand on a corrugated box, which can have any form, color, design, or configuration. The smallest company can appear to be a major competitor by creating a sophisticated and quality design to put on their shipping boxes. Custom branding impresses customers and presents a professional appearance.

5) Biodegradable and Eco-Friendly

The most important feature of corrugated boxes is their ability to be recycled and repurposed. In this age of environmental awareness, every company is striving to develop a way to protect and sustain the environment. Since over 70% of the material used to produce corrugated boxes is recyclable, corrugated boxes are an essential part of a company‘s efforts in proving it is environmentally wise. According to governmental regulations, corrugated boxes are assembled using glues and materials that are non-pollutant and ecologically friendly according to governmental regulations.

6) Lightweight Materials

A major factor in any shipping operation is the control of cost, which can be increased by shipping heavy materials in heavy boxes. Since corrugated boxes are lightweight but strong, they are the perfect solution to weight shipping problems. Regardless of their weight, corrugated boxes still have the strength to ensure the safety of any product.

Corrugated Box

7) Flexible Paper Types

One of the advantages of corrugated fiberboard is its many types, including single, double, and triple-walled, which can be produced from a variety of paper types depending on shipping needs. Any product that a manufacturer can produce can be shipped using a corrugated box.

8) Inexpensive and Custom Printing

Corrugated fiberboard is an inexpensive material for printing company graphics, logos, brand names, and graphics. Included in the production of most fiberboard is a customizable printing process for the application of designs. Custom printing is a vital part of the branding process and is one of the least expensive since it does not require additional advertising costs or an advertising agency. The layer of flute protection and flat surface for printing make corrugated boxes the bridge between marketing and logistics.

The use of corrugated boxes provides companies with the opportunity to creatively develop their professional, personalized logistic tool. A well-designed and engineered box can be tailored to fit the culture and personality of a business. The extra effort to create a company corrugated box will differentiate a business from its competitors and place a professional image in its market.

9) Product Safety

A corrugated box is an insurance policy for products that have to travel long distances through various conditions to make it to market. The flutes and walls of a corrugated box may be the only defense a product has against the environment and the ill-treatment it may receive during shipping. The extra cushioning is protection against shocks, abrasions, vibrations, and being tossed about on a plane, truck, or train.

Aside from preventing damage from abuse, corrugated boxes can protect the most fragile products, such as perfume, colon, and chemicals, from exposure to dirt, grime, dust, and bacteria. The fiberboard of a corrugated box serves as a shell casing that ensures the safe delivery of products.

10) Sustainability

A major dynamic in modern business is sustainability, where only as much is used as needed to match what is being resupplied. Corrugated boxes fit easily into the sustainability model since they can be repurposed at the end of their usefulness and put back into the supply chain. This factor removes the concept of diminishing returns since a company can never run out of corrugated material or boxes.

11) Meets Global Recycled Standard (GRS)

The GRS is owned by the Textile Exchange, an organization with several industry partners that support joint climate and biodiversity initiatives. The range of products covered by the GRS under the Textile Exchange goes beyond the limitations of the textile industry to include a wide range of products that have recyclable content.

Included in the certification standards for the GRS are social, environmental, and chemical criteria to verify responsible practices.

The GRS certifies organizations using various parameters, which include:

  • The Reclaimed Material Declaration Form guarantees that materials that would have gone into landfills will be reclaimed.
  • A Transaction Certificate identifies the transfer of ownership and must declare the pre-and post-consumer recycled content of the materials.

Corrugated Box

5. Conclusion

To sum up, a corrugated box is a disposable container whose side is composed of an inner layer, an outer layer, and an intermediate layer of material.