Corrugated box is widely used as product packaging due to its light weight, printability, low cost and many other advantages. In order to improve the space utilization of the warehouse, the boxes are usually stacked together. For this reason, one of the important functions of a corrugated box is to provide crush resistance (product protection) and adequate strength for stacking in warehouses. There are many factors that can influence stacking strength of corrugated box, such as the internal structure and the content of water.

The corrugated box must have sufficient stacking strength, otherwise the boxes located at the bottom of the stack may be deformed or even crushed by the compressive loads applied onto their faces to diagonally opposite edges, or to corners. Therefore, before stacking, the stacking strength of the corrugated box must be tested to guarantee its performance during storage or transportation.

This article provides a simplified test method for stacking strength of corrugated box for your reference. The specimens are supplied by one corrugated box manufacturer. The testing instrument is Labthink’s XYD-15K Box Compression Tester.

Figure 1. Common Corrugated Boxes

The tests can be performed according to the following procedures.

(1)   Fill the corrugated box with content (product) or similar content and then seal the box in the same way as it is shipped.

(2)   Measure the dimension of the corrugated box.

(3)   Place the corrugated box on the lower platen of the instrument. Calculate the preload applied on the box according to the number of the stacks and compressive force of each stack. Set preload and time and other test parameters.

(4)   The upper platen of the instrument will move downward until it reaches on the surface of the box. When the preload is reached, the system start counting test time.

(5)   When the preset test time is reached, the test is stopped. Then remove the specimen and measure its dimension after test.

By measuring the dimension before and after stacking strength test, the user can calculate the deformation rate of the corrugated box under certain load and determine whether the tested corrugated box can meet the requirements for stacking.

For more details about XYD-15K Box Compression Tester, please visit www.labthink.com

About Labthink Instruments Co., Ltd:

Labthink Instruments Co., Ltd is one leading supplier of packaging testing instruments, which is headquartered in Jinan, China and operated in Boston, U.S.A.