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Conversion Chart for Edge Crush Testing

Conversion chart for edge crush testing

Edge crush testing, also known as ECT, is a cost effective and convenient way to work out the peak load that a material can handle. It is one of the most popular ways of measuring the strength of cardboard, paperboard and corrugated paper.

If you’re using cardboard in your packaging or products, ECT is invaluable in helping maintain and improve quality control. Make sure you’ve wrapped your head around exactly what your ECT results mean for your corrugates with the help of our conversation chart and breakdown.

Why use an edge crush test?

Unlike Mullen burst testing, which is particularly useful for working out how much rough handling a cardboard box can take, ECT is perfect for getting a good picture of overall strength. This is useful for the packaging and corrugated cardboard of today, which is much lighter and more durable than traditional cardboard boxes.

It is also essential for a clearer broad picture. While the Mullen burst test remains an industry standard, it requires a minimum board base weight. This baseline is now being challenged by the introduction of more recycled materials in corrugated board products. The change in composition revealed that composites with recycled components weren’t performing as well in the Mullen test despite the fact they had very good compression and damage resistance qualities. ECT offers an easy way to determine these qualities.

Edge crush testing is good for determining a box’s stacking durability as well as the maximum weight it can carry.

How does edge crush testing work?

ECT measures the edgewise compressive strength of corrugated board by compressing a piece of the board between two rigid platens. This pressure is applied perpendicular to the direction of the boards’ flutes. When the board collapses, it has reached peak load and the amount of pressure required to reach this state is recorded.

The load that a sample of corrugated board can withstand is reported as force in pounds per lineal inch of load bearing edge (lb./in). This is different to Mullen Burst Testing, which notes results in pounds. This means that a box with burst rating of #200 is one that can withstand up to 200lbs of force before rupturing. The same box would have a 32 ECT rating.

Edge crush testing conversion chart

Box Mullen Burst Test Edge Crush Test Max. Load per Box
Standard 200# 32 ECT 40lbs
Heavy Duty 275# 44 ECT 65lbs
Heavy Duty + Double Wall 275# 48 ECT 80lbs

 

ECT with Industrial Physics

Looking for a new edge crush testing solution? Hoping to upgrade from a burst or Mullen test or planning to add an additional machine to your line-up? We’ve got the expertise to help. Our years working in corrugated and packaging testing mean we are well placed to advise. If you’d like to hear more about how to design and implement a testing setup to suit your products, get in touch with our corrugated specialists.

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FAQs

  • Edge crush testing measures the strength of corrugated cardboard by determining its resistance to crushing along the edges.

  • The conversion chart helps translate edge crush test results into equivalent values for different cardboard grades.

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