Corrugated products are used for storage, packaging and shipping of products to warehouses, factories and stores. They are also used for gift packing, displaying grocery store items etc. The compressive strength of corrugated carton or the load bearing capacity is at the side walls. The compressive strength purely depends on the perimeter of the carton, i.e. longer the perimeter, higher the compressive strength. The vertical corrugation has the capacity to bear more load than the horizontal corrugation. So, at the time of stacking, the boxes must be vertically corrugated.

It is important to note that in the whole process of load bearing, 2/3rd of the total pressure is taken by the four corners of the boxes. So, they are prone to maximum damage. Proper alignment at the time is stacking must be ensured as the little deviation of stacking can damage the strength of the boxes. The number of stacking layer also influence the strength of boxes as it affects the mechanical properties of the cartons. The bottom layer is the most affected at the time of stacking and the load taking capacity depends on the bending deflection. At the time of transportation, the cartons undergo vibration from all directions which leads to thinning of carton walls.

The Box Compression tester measures the compressive strength of the box. The test can be initiated by placing the sample between the two plates. The plates move towards each other and exert a load on the sample box. The plates use a hydraulic press to be operated. After the box is compressed and deformed, the force that is applied is measured. The formula to calculate the compression strength is:

BCT=k1*ECT*✓h*Z

Where:

K1 is 5.87(Constant value)

ECT= edge crush value (pounds)

H=Corrugated Fibreboard (CFB) thickness (inches)

Z= box perimeter (inches) = 2(L+W)

The Box compression tester gives an accurate result with the help of a chip based display unit. Hold Peak and Tare values and has a strong base plate to conduct the test efficiently. It has an overall capacity of 500kgf with ±2% full scale. The least count measure is 200gm with a test platform size of 450*450 mm. The speed of the test is 12.5±2.5 mm/min. It adheres to ASTM D642, ASTM D4169, TAPPI T804, ISO 12048 and JIS Z0212 standards.