ECT - Testing

For the testing of ECT (Edge Crush Test), specimens are cut with a length of 100 mm and the width of 25 mm from conditioned board. ECT then is measured in a compression tester with the specimen standing with the glue lines vertically.

10 individual specimens are crushed and the average is calculated and reported in kN/m. 7 % variation is normal for a good corrugated board. The American method with wax dipping the edges of the test specimen or the Japanese method with "neck down" may somewhat reduce the variation but even better is the calculation of ECT from the crush resistance of the components liner and fluting.

With a razor blade slitter test sheets 100 mm wide are cut from the board, with the cuts being made parallel to the flutes. The Billerud cutting table is a handy tool for this purpose.

From the test sheet, test pieces 25 mm wide are cut perpendicular to the flutes. It is very important that the cut edges are straight, clean and parallel and perpendicular to the flutes. A special precision cutter has been developed by Billerud and this device is now marketed by AB Lorentzen & Wettres Maskinaffdr, Stockholm under the trade name "Billerud cutter".

Scope And Application

This test is used to determine the compression rigidity of corrugated board and solid fiberboard above 800 um. This property is related to the prediction of a board's performance when used in cartons or fiberboard cases.


A test piece is subjected to an increasing force applied in the direction of the shorter dimension of a sample strip in a compression tester conforming to standard design

Test Piece Holder

The holder consists of two bare of rectangular cross section which can be held together such that the full length and 19 mm +/- 0.2 mm of the test piece is securely clamped in a vertical position.

Cutting Device

Ten strips must be cut with absolutely square edges. Solid board test strips may be cut by guillotine.

Corrugated board strips are cut using the illustrated cutter.


Samples and specimens to be selected according to intended application of tent, i.e. as required for routine testing or in accordance with BS 3430.


Preparation and Conditioning of Test Pieces

Condition specimens in accordance with BS 3431 (Test conditions 65% R.H and 20 degrees C). Cut sufficient test pieces for test purposes. For normal needs board is only tested in the "across machine" direction, i.e. grain running in the longer dimension of the strip. Tests may be conducted in machine direction as required. Strips must be cut cleanly and with parallel edges.

Test pieces should be cut:

100.0 +/- 0.1 mm X 25.0 +/- 0.1 mm



Test in standard conditioning atmosphere. Place specimen strip in the holder tighten sufficiently to ensure strip is vertical without damaging the specimen. Operate the tester until the test piece collapses. Record the maximum. force sustained by the test piece before collapse to the nearest Newton.


1) For machine-direction and across machine-direction separately, the mean of the test results to the nearest Newton together with the range of results. Results should be reported in units of KN/M.

2) Any deviation from this standard method