Basic Information for Transport Packaging Design

The objective of transport packaging is preservation of the product in its delivery from point of manufacture to the customer. Without packaging, most products would have a difficult and expensive trip through handling and transportation, many of them delivered to customers in a damaged condition. Transport packaging actually adds to the value of the product, by lowering the cost for customers to obtain possession of the product from its origination.

Transport packaging, also known as "distribution packaging" in North America, includes the shipping container, interior protective packaging, and any unitizing materials for shipping. It does not include packaging for consumer products such as the primary packaging of food, beverages, pharmaceuticals, and cosmetics. In the USA transport packaging represents about one-third of the total purchases of packaging; the balance is attributable to primary packaging for consumer products.

The goal in transport packaging is to provide the correct design for packaging such that its contents will arrive safely at its destination, without using too much or too little packaging material. In other words, the package designer must assure that this equation is maintained:

The following will demonstrate how to determine the right amount of each of the three variables so the equation will always balance, with no excessive over-packaging cost nor loss from damage.

The functions of transport packaging can be summarized as follows:

• Containment - The basic purpose of packaging is to contain the product. Packaging permits products to move from their source to the customer, supplying use value to products which are otherwise useless to the customer who is usually remote from source.

• Protection - Most products require some degree of protection from the hazards in distribution. Packaging furnishes the degree of protection needed to safely transport products from source to customer

• Performance - Packaging aids in transportation, handling, storing, selling and use of the product. This function includes such things as orientation of the product, ease of identification, appropriate quantity, ease of disposal, handling features.

• Communication - The package must identify its contents and inform about package features and handling requirements. It generally provides space for shipping information as well.

To design a transport package one must have Goals or Objectives in mind. These will vary with products, customers, distribution systems, manufacturing facilities, etc. but most, transport packaging should address the following objectives:

Product Protection - The primary purpose of any transport package is to insure the integrity and safety of its contents through the entire distribution system.

Ease of Handling and Storage - All parts of the distribution system should be able to economically move and store the packaged product.

Shipping Effectiveness - Packaging and unitizing should enable the full utilization of carrier vehicles and must meet carrier rules and regulations.

Manufacturing Efficiency - The packing and unitizing of goods should utilize labor and facilities effectively.

Ease of Identification - Package contents and routing should be easy to see, along with any special handling requirements.

Customer Needs - The package must provide ease of opening, dispensing, and disposal, as well as meet any special handling or storage requirements the customer may have.

Environmental Responsibility - In addition to meeting regulatory requirements, the design of packaging and unitizing should minimize solid waste by any of the following: reduction-return-reuse-recycle.

Since transport packaging should always be economical, the above goals should be balanced or optimized to achieve the lowest overall cost.

The scope of design in transport packaging must consider all aspects of the distribution system including customers, carriers, and distributors as well as the manufacturing plant, packaging line, warehousing and shipping. Successful package design is a total system approach.

Once created, a package does not magically form around the product, float through shipping, travel hundreds of miles in isolation, arrive at the customer’s site and disappear. It has an influence on and is influenced by everyone and everything it encounters. Many of these encounters will affect manufacturing and distribution costs, or products integrity with indirect impact on sales. Therefore such events should be considered in the design process.

Unfortunately, there is often too much focus on the cost of packaging materials to the exclusion of other factors, including cost-related ones in handling, storage and transportation. If the package is slightly larger and/or heavier than it really has to be, costs in all three areas will be higher than necessary, perhaps producing an even greater effect on profits than would higher packaging costs for a smaller/lighter package.

For instance, although each industry and company is different, a general rule of thumb states that transportation will cost between 3 to 10 times as much as packaging on average for all shipments. A small reduction in package size or weight could mean much more savings in transportation plus handling and storage. For example, a small kitchen appliance in bulky wrap-around die-cut may involve less material cost, but molded packaging may pack faster and require less cube, permitting more pieces per unit load, fewer handling trips, more units per storage cube, and more units per truckload…for an overall savings.

An inverse relationship exists between packaging cost and maintaining product integrity with low damage rates. Other factors being equal, an increase in packaging will provide more protection to the contents and therefore lower the potential for damage. Or conversely, cutting packaging costs without other improvements generally means less protection and higher damage rates.

The real cost of getting the product safely to market is the sum of packaging and damage. Optimizing the total is the true goal of packaging design. If damages rise too high, both replacement/repair costs and potential for loss of customer good will and cancellation of orders increase.

No matter where packaging design takes place, in engineering, manufacturing, shipping, or at the supplier, all factors above must be considered, costed, and involved in a total system approach.

Here is a proven 10-step procedure which assures that a transport package design will provide maximum performance at least overall cost.

1 - Identify the Physical Characteristics of the Product

Product knowledge means more than knowing simply its dimensions and weight. The package designer must be aware of surface characteristics and susceptibility to abrasion or corrosion, the ability to hold a load in compression, internal characteristics affected by vibration, and particularly the product’s fragility. Guessing about any of these factors will surely lead to potential problems.

Package design must incorporate marketing and distribution requisites in addition to product characteristics. One must know: the number of units that will ship in a container; the composition and attributes of the primary package; the identity of customers and their handling and storage requirements, the package disposal criteria, total volume expected per shift/day/year, expected life cycle, the planned modes of transport, types of distribution channels, etc.

It was emphasized earlier that knowledge of the distribution environment is key to designing an optimum package. Major hazards to be expected in the environment are: rough handling; vibration and shock in-transit; compression in storage or in-transit; high humidity and water; temperature extremes; and puncturing forces/concentrated impacts. Learning about them may include observation, reading other’s research, or conducting measurements.

There are many alternatives available for shipping containers, interior packaging, and unit loads. All should be considered and reviewed before selecting the final types for further development. Trade-off analysis techniques such as make vs. buy often help. Rather than considering only materials that one has experience with, comparing paper vs. plastic vs. wood vs. metal is a good exercise at times to assure the best for the particular project. Once the basic materials have been selected, detailed work on design can begin.

5 - Design the Shipping Unit (Container, Interior Packaging and Unitload)

With basic materials and information established in steps 1-4, the designer can now scientifically engineer a distribution package, and unitload where appropriate. Each component of the shipping unit (container-interior-unitload) is analyzed for strength and other required properties and compared to technical data available from suppliers. Some packaging materials have good design data available, but most do not. The designer frequently must rely on experience to reach a successful solution; the novice may find that lack of information makes it difficult to arrive at an optimum solution. In that case, suppliers or consultants may be of help.

Trial and error can be shortened for the novice, as well as the experienced designer, by conducting engineering tests in package development. Impact, vibration and compression testing in the lab not only identifies shortcomings but helps to fine-tune to the optimum solution.

After the shipping unit is designed, perhaps with the aid of engineering development tests, it should then be performance tested. This consists of subjecting the unit to a sequence of anticipated hazards/tests in the laboratory for the purpose of a pass/fail decision. Will the shipping unit protect its contents all the way through distribution?

The performance test methods should be based on industry standards. Such standards have considerable experience and history behind their development and use, and a successful completion of the test sequence almost guarantees damage-free shipments. The most widely used standard is the International Safe Transit Association’s Procedure 1, in use since 1948. The 1982 approved ASTM D-4169  provides a more complete array of distribution possibilities and identified hazards with corresponding test sequences, and permits the user some flexibility in selecting test intensities. For users who can clearly define their distribution cycles, but find them different than the standard cycles in D-4169, the ASTM standard also provides a means of developing a unique sequence of tests, resulting in performance tests which can more precisely simulate the actual conditions.

There is an old saying which goes - One Test Is Worth 1000 Expert Opinions. Often performance test results fool even the most experienced engineers and it is necessary to repeat an entire cycle of redesign and retesting as many times as required to reach a "pass" decision.

8 - Redesign the Product Where Indicated and Feasible

Occasionally testing reveals a product weakness which can be compensated for by protective packaging, but at excessive cost. If at all feasible, the product should be redesigned to correct the weakness rather than redesigning the package. This is particularly important when the cost of the redesigned product is less than the increased packaging.

It is usually difficult for package designers to bring about product redesign when they are located organizationally in other than the product engineering group. If this is the case, the packaging designer should attempt to establish a continuing line of communication with the product engineers. Sometimes this means educating product engineers in the hazards of distribution and showing them how to correct product weaknesses.

An important part of package design is packing of the product in the shipping container and unitizing of containers. Although this may be the responsibility of someone else, i.e. Industrial Engineering, the designer must be aware of cost factors and the appropriateness of mechanizing or automating all or part of the operations. Sometimes a trade-off in package design must be implemented to achieve overall system economics.

One step repeatedly overlooked in the design process is documentation. This includes documenting test results, specifications, drawings and methods of packing. Drawings should be in company standard formats with appropriate designations for reference in the corporate spec system. Relying on supplier sketches or drawings as the reference document is not a wise idea. They should be transferred to company format so purchasing, manufacturing and engineering can reference them.

On any package design project, apply these 10 steps. Then check your work against the following Checklist. Doing so will significantly reduce potential of an unpleasant surprise when shipments begin.

Checklist for Each Package Design Project