To manufacture packaging products, the ratio of usage of Cardboard products is very high. This is why corrugated boxes are popular in the packaging industries. Be it two-ply, three-ply or multi-ply corrugated boxes, you can choose any as per the requirement of the application.

These boxes are eco-friendly in nature, durable and cost-effective. But all the corrugated boxes are not equal in terms of quality. So, to test the strength of these corrugated boxes, it is important to perform certain types of tests in terms of chemical resistance, thickness, compressive strength and a lot more.

Whenever choosing a corrugated box, you must be aware of its quality. The construction quality and strength of the box will help you analyze how much weight the box can withstand. If the box is weak in nature, it will get punctured during warehousing and transportation. On the other hand, if the box is very bulky in nature, it means you are paying a few extra bucks for that material and also adding to environmental wastage.

To help you determine how to choose the right corrugated boxes, we have jotted down a few testing procedures. Let’s have a quick glimpse of the test process that you can run on the corrugated boxes and then will discuss those in detail.

• Bursting Strength Test
• Edge Crush Test
• Cobb Sizing Test
• Vibration Test for Packaging
• Box Compression Tester
• Grammage Test

First, is the Bursting Strength Test.

About : It tests the bursting strength of a box when subjected to predefined amount of pressure
Purpose: To evaluate the exact weight a corrugated box can tolerate during rough handling

Also known as Mullen Test, Bursting Strength Test helps to measure the toughness of the walls of a corrugated box when provided to force or pressure. During the test procedure, a sample of corrugated board is placed on a rubber diaphragm to apply pressure to the sample until it bursts.

The rubber diaphragm is expanded using hydraulic pressure. As the diaphragm increases, the corrugated board bursts due to excessive pressure.

Formula to calculate bursting factor is as below:

Bursting factor = Bursting strength x 1000 / Grammage

Where, Bursting strength is measured in kg/cm2
And grammage is measured in gm/m2

Second is the Edge Crush Test (ECT).

About: Crushing of a corrugated board
Purpose: To test the stacking strength and material quality

Another most popular method to test the stacking strength of corrugated boxes is the Edge Crush Test or ECT.

As discussed earlier, corrugated boxes are made of two or more layers of sheets. In layman language, thin sheets with grooves and ridges pattern is sandwiched between two flat sheets and so on to make it two ply or three ply. These grooves provide immense strength to the boxes which explains that a box can easily bear a huge amount of pressure even when exerted from one direction.

Packaging boxes bear a huge amount of pressure from one side especially when they are placed one above the other during warehousing or transportation. Edge Crush Tester or Flat Crush Test or Ring Crush Test helps to determine this strength of the corrugated boxes.

Hope you have got good information in this blog.

Keep following us, we will talk about the rest of the testing techniques in the next part of the blog. Stay Tuned! Next Blog- 2