There are different parameters on which a corrugated fibre board is a quality tested. A good board should have high bursting strength, provides a good cushion to the packing, should have high resistance against physical impacts and weathering conditions. Although, Edge crush test, i.e. ECT is popularly performed.
Cardboard Edge Crush Test (ECT)
It not only simple to perform test but can be substituted for Box compression test. In this test, the raw material that is going to be used for the production is a test prior to use in the production cycle. Whereas, in BCT, an end product is tested. Moreover, BCT is a destructive test. This test tells a lot about the stacking ability when stored in a warehouse or during transits.
In paper and packaging industry, Edge Crush Tester is the most commonly used testing machine. Since, years, this test result has been accepted worldwide to adjudge the box strength. In this test, a sample is prepared, preferably square or rectangle and made to stand edgewise while corrugators are perpendicular to the horizontal axis. A predefined load is applied to see the behaviour of the sample.
Sample preparation is a very crucial aspect of this test. The sample has to be clean, cut precisely as per dimension defined, without any deformity. If the specimen prepared is damaged prior to testing, it will collapse prematurely and does not provide accurate test results.
There are many formulae defined in the standards that can be used to derive the box compression test values by using the observed values of ECT. Hence, this is a convenient way to skip the crush test for a carton as BCT can be easily calculated from ECT.
Using the values observed from ECT, the stacking height can be easily estimated along with the weight of the box. Other factors like packing effectiveness, internal supports, humidity, the length of storage and stacking methods can be used to further improve the calculation for deriving crush strength of a carton.
ECT Versus Burst Test
With the determination of more accurate results with ECT, it has been preferred over the bursting test. Especially in industries like footwear, ECT has completely replaced the Burst test as cartons were failing despite passing the tests. ECT provides an ample of information about the behaviour of the box in real time working conditions. Burst test is unable to determine the endurance of the corrugated fibre boards. Thus, Presto is glad to see how Edge Crush Tester is being adopted by industries for generating reliable reports.