Edge Crush Test vs. Box Compression Test

Edge Crush Test vs. Box Compression Test (aka ECT vs. BCT): New Performance Metrics for Corrugated Square Off

by Rob Kaszubowski, CPP

Chainalytics

As packaging consultants we are constantly faced with the challenge of learning a client’s vernacular and acronyms – as well as common acronyms within the packaging industry. For years the standard for corrugated packaging has been the ECT or Edge Crush Test. Edge crush slowly surpassed Mullen burst as the standard metric for corrugated strength. (Read more about ECT vs. Mullen Burst Here).  The ECT value is then utilized to help calculate the “theoretical box compression strength” which is derived from the McKee formula which dates back to the 1960s.

Lately, the more common term around the industry is now the BCT value or Box Compression Test. This value is often tied to a company’s packaging specification as part of their performance spec requirements.  That means that depending on a number of factors (the weight of the box contents, stacking pattern, safety factor, length of storage, storage conditions, etc.) a company may call out a target compression value that their secondary packaging must meet as a minimum threshold for performance.

So for example, a very simple requirement in the past may have been:

§  Box style = RSC

§  Size = 15 x 12 x 10

§  Material = 44# C ECT Kraft

Now that same company may specify the BCT (Box Compression Test) value:

§  Box style = RSC

§  Size = 15 x 12 x 10

§  BCT = 940 lbs

At the end of the day the customer doesn’t care what makes up this box, or what the paper combinations are. They just want to be sure that it can hold 940 pounds and make it through their supply chain with their products unscathed.

To perform the ECT test, a 2” x 2” swatch of corrugated is cut from a sample sheet stock. It is placed in an edge crush tester machine and thus the ECT value is obtained.  

Common ECT target values include:

§  26 (B or C flute)

§  32 (B or C flute)

§  44 (B or C flute)

§  55 C flute

§  42 BC flute

§  48 BC flute

§  51 BC flute

§  61 BC flute

§  71 BC flute

Corrugated board consists of three combined layers of paper: a single face liner, medium, and double face liner. Just as there are multiple ways to slice up a pizza, there are also multiple combinations of paper that can equal a certain ECT value. The weight of the paper liners used typically depends on what paper weights the supplying paper mills typically carry and source to the corrugators.  The amount of recycled content or virgin fiber can also be a factor in the final ECT value.

Anatomy of Corrugated Board

So as companies look to standardize their packaging and consolidate sourcing they are looking towards a much more simplified corrugated box specification: one that no longer calls out the ECT value, but rather the BCT value. Packaging engineers and procurement teams are stating: I don’t care what you make the box out of, as long it meets my minimum strength thresholds. This shift in the market should ultimately make it easier for suppliers to focus on running paper combinations that they run well and run fast and deliver an optimized product.

If you have questions about what your minimum BCT values or stacking safety factors should be for your secondary or tertiary packaging, contact the packaging engineering team at Chainalytics.

Product Packaging Strategies to Maximize Profitability

by Kyle Ous
@PKGPlaymaker
Chainalytics

When it comes to designing products for the marketplace, it seems there are countless tasks to complete before products are introduced and available on the retail shelves. While speed to market is important, packaging design is a critical component to the overall profitability of the product and is important to evaluate before entering the marketplace. Does this mean companies need to follow a rigorous packaging engineering design process and justify each added cost?

Companies that are best in class are doing iterative package design analysis and testing before phasing in new packaging. Although this is an involved process, this task prepares the packaged product for distribution year-over-year and enables companies for future growth within their categories.

Profit margin is a key metric for success. As it relates to packaging, there are a handful of ways to maximize this metric. It is important to understand the supply chain channels that your customers are using to buy their new products. Online retail sales are a growing channel and seem to be a popular buying experience across many demographics.

Keurig 2.0 On Shelf Retail Package for Consumers

Keurig 2.0 coffee maker systems are using customized packaging strategies for different supply chain channels through to the customer. Out of the box, Keurig utilizes high-end lithographic labels with an integrated carrying handle for sales at the retail shelf. Although the packaging is more expensive, it tends to differentiate from other products on shelf and offers enhanced customer experience in the final mile. Contrary to popular belief, the same packaging does not need to be used for online sales or replacement parts that are sent directly to the consumer. Kraft corrugated with direct print on the outside of the shipper box is a cost effective alternative to retail packaging. Typically a 15-30% cost-take-out can be achieved in this simple, yet operationally challenging opportunity.

Online direct to customer packaging of similar product

Companies that utilize best-in-class packaging strategies are continuously analyzing different ways to maximize profit margin. One simple truth behind packaging is the most successful design concepts plan for transportation efficiency and minimize the amount of packaging related damage through package testing. Inside the box, Keurig uses an engineered cushioning design made out of molded pulp for the Keurig 2.0 system. In this example, retail sales and online sales use the same style and type of cushioning to protect the product. While the supply chains are different, the performance of the cushion was likely tested for both shipping environments. 

If you are looking to become ‘best-in-class’ in your category, packaging strategy and alternatives are a ‘must-have’ on your packaging design check sheet. Feel free to reach out to kyle.ous@chainalytics.com if you’d like to sound out alternatives and logical steps in your design process with our Packaging Consulting Services at Chainalytics.