Determination of edge compression strength of corrugated board

Foreword

This standard is equivalent to ISO3070:1987 "Corrugated fiberboard-Determination of edge crush resistance".

This standard is a revised version of GB6546-86 "Determination of edge crush resistance of corrugated fiberboard".

This standard is prepared in accordance with GB/T1.1-1993 "Guidelines for Standardization Work Unit 1: Rules for Drafting and Presentation of Standards Part 1: Basic Provisions for Standard Preparation".

From the date of implementation, this standard will replace GB6546-86.
Drafting unit of this standard: China Pulp and Paper Industry Research Institute.
Main drafters of this standard: Li Lanfen, Zhang Shaoling.
This standard was first issued on June 30, 1986.

National Standard of the People's Republic of China GB/T6546-1998idt ISO3070:1987

Determination of edge crush resistance of corrugated fiberboard replaces GB6546-86
Corrugated fibreboard-Determination of edgewise crush resistance

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1 Scope

This standard specifies the determination method of edge crush resistance of corrugated fiberboard.

This standard applies to the determination of edge compression strength of single-flute (three-layer), double-flute (five-layer), and triple-flute (seven-layer) corrugated cardboard.

2 Reference standards

The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the feasibility of using the latest version of the following standards.

GB450-89 Paper and cardboard sample collection

GB10739-89 Standard atmosphere for handling and testing of pulp, paper and cardboard samples

3 Test principle

The rectangular corrugated cardboard sample is placed between the two pressure plates of the compression tester, and the corrugation direction of the sample is perpendicular to the two pressure plates of the compression tester, and then pressure is applied to the sample until the sample is crushed. Measure the maximum pressure that each sample can withstand.

4 Test instrument

4.1 Fixed pressure plate type balance wing electronic compression tester

The compression tester is operated by a fixed pressure plate and another direct rigid drive pressure plate, and the moving speed of the dynamic pressure plate is (12.5±2.5) mm/min. The size of the pressing plate should meet the selected size of the sample so that the sample does not extend beyond the pressing plate. The pressing plate should also meet the following requirements:

a. The parallelism deviation of the pressing plate is not greater than 1:1000;
b. The lateral movement does not exceed 0.05mm.

4.2 Bending beam compression instrument

This compression instrument is based on the working principle of beam bending, and the requirements for the upper and lower pressing plates are the same as those of the fixed pressing plate electronic compression instrument. During the test, the scale at the moment of crushing should be within the range of 20%-80% of the deflection range that the instrument can measure; when the pressing plate begins to contact the sample, the speed of the pressing plate pressure increase should be (67±13)N/s.

When using this instrument for testing, it should be noted in the report and shall not be used for cutting inspection.

4.3 Sample cutting device

A band saw or knife can be used, or a mold can be used to prepare the sample, but the edge must be cut smooth, straight and perpendicular to the surface of the cardboard.

4.4 Guide blocks

Two polished and shaped metal blocks with a cross-section size of 20mm×20mm and a length of less than 100mm; the guide blocks are used to support the sample and make the sample perpendicular to the platen.

5 Sample collection and processing

5.1 Sample collection shall be carried out in accordance with the provisions of GB450.
5.2 The sample shall be subjected to temperature and humidity treatment in accordance with the provisions of GB10739.

6 Sample preparation

Take a rectangular sample with the short side in the corrugated direction, with a size of (25±0.5)mm×(100±0.5)mm. There shall be no indentation, printing marks or damage on the sample. Unless agreed by both parties, at least 10 samples shall be cut.

7 Test steps

Sampling and testing shall be carried out under the atmospheric conditions specified in Article 5.2.

Place the sample in the middle of the platen so that the short side of the sample is perpendicular to the two platens, and then support the sample with a guide block so that the end face is perpendicular to the space between the two platens, and the two guide blocks are parallel to each other and perpendicular to the surface of the sample.

Start the balance wing tester and apply pressure. When the pressure is close to 50N, remove the guide block until the sample is crushed. Record the maximum pressure that the sample can withstand, accurate to 1N.
Test the remaining samples according to the above steps.

8 Result expression

The vertical edge compressive strength is calculated according to formula (1) and expressed in N/:

R = F × 103 / L

Where: R—vertical edge compressive strength, N/m
F—maximum pressure, N;
L—size of the long side of the sample, mm.

9 Test report

The test report includes the following:

a. The number of this national standard;
b. Sample type and specification;
c. Standard used in the test;
d. Atmospheric conditions of the test site;
e. Model and pressure speed of the test instrument used;
f. Arithmetic mean of the test results;
g. Other information that helps to explain the test results.