FLAT CRUSH RESISTANCE (FTC)
Purpose of the test
This test is performed to determine the flat crush resistance of corrugated board.
Procedure
Operate the instrument in accordance with ISO 3035 and the manufacturer’s instructions.
Leave the samples exposed for 24 h to 23°C and 50% R.H., according to ISO 187.
Cut one test piece of at least 50 cm² from the middle of each sheet.
Place the test piece with the corrugations parallel to the length of the tester beam to prevent leaning corrugation due to the sideways movement of the platens.
Check on leaning corrugation and report this addition “LC” on the form.
Report 10 measures for the maximum force sustained by the test piece before collapse of the fluting (be aware that there might be more than one peak) in kPa, their mean and standard deviation calculated to 3 significant figures.
ISO 3035
Nr. of samples
12 test pieces per level
Size: 140 x 140 mm²
Special size A4, A3
Levels
Level 1: 100÷250 N
Level 2: 300÷450 N
Reporting
Report 10 valid results of measurements in kPa, their mean and their standard deviation. All to three significant digits.