GB/T 6543-2025Single and double corrugated boxes for transport packages (English PDF)

3.1 Corrugated fiberboard

A composite fiberboard consisting of one or more layers of corrugated paper bonded between several layers of paper or fiberboard.

[Source. GB/T 6544-2008, 3.1.2, modified]

3.2 Corrugated box

A box made of corrugated fiberboard (3.1) as the main material.

3.3 Inside dimension of length plus width and depth

The sum of the length, width and height of the inner dimensions of the box.

[Source. GB/T 16717-2013, 3.1]

3.4 Hole of box corner

Holes at the corners of a corrugated box (3.2) after it is formed.

3.5 Prime section

The part of the printed image that reflects the theme.

3.6 Subprime section

Any part of the printed image or text other than the prime section (3.5).

4.1 Types of corrugated boxes

Corrugated boxes are divided into 2 categories and 20 types based on the maximum mass of the contents, the inside dimension of length plus width and depth, the distribution environment, and the type of corrugated fiberboard used. See Table 1.The performance of the corrugated fiberboard used in each type of corrugated box must not be lower than the specified values in Table 1 of GB/T 6544-2008.Category 1 boxes are primarily used in relatively harsh distribution environments, while Category 2 boxes are primarily used in more favorable distribution environments.

4.2 Basic box type and code

The basic types and codes of corrugated boxes are listed in Annex A. Depending on the contents, other types of corrugated boxes may be used. Corrugated boxes may contain accessories such as partitions, padding, and bases. Their types and codes are listed in Annex B.

5.1 Appearance

5.1.1 The outer surface of the corrugated box should be smooth and free of obvious defects such as dirt, scratches, and corner wrapping. The outer surface of the box should not have obvious color differences within the same batch of boxes.

5.1.2 The content of printed labels on corrugated boxes should comply with the

requirements of the drawings confirmed by both the customer and the supplier, with clear patterns and texts and no obvious color difference.

5.1.3 The nails on the corrugated boxes should be firmly nailed and fully nailed. There should be no defects such as overlapping nails, warped nails, or poor corners.

5.1.4 There should be no defects such as glue overflow and glue see-through when bonding corrugated fiberboard boxes.

5.2 Dimensions and deviations

The external dimensions of rigid rectangular corrugated boxes should comply with GB/T 4892.The dimensional tolerances for length, width, and height should be ±3 mm for single corrugated boxes and ±5 mm for double corrugated boxes. The unfolded dimensions, internal dimensions, external dimensions, extension, and their relationships for 0201 boxes are shown in Annex C. Other boxes may refer to this guide.

5.3 Squareness

For boxes with an inside dimension of length plus width and depth not exceeding 1000 mm, the difference between the lengths of the top and bottom diagonals should not exceed 5 mm. For boxes with an inside dimension of length plus width and depth exceeding 1000 mm, the difference should not exceed 8 mm.

5.4 Hole of box corner

When the box is stretched and formed, the maximum size of the hole of box corner of the box should not be greater than 5 mm.

5.5 Nailing

When nailing, the spacing between nail lines should be no more than 80 mm for a single nail and no more than 110 mm for a double nail. Nail along the centerline of the overlapping portion, using diagonal nails (at approximately a 45° angle to the vertical edge of the box) or horizontal nails. The distance between the top end of the head nail and the centerline of the top indentation and the bottom end of the tail nail and the centerline of the bottom indentation should be no more than 25 mm. The width of the tongue edge of the nailed overlap of corrugated boxes should be no less than 30 mm for single corrugated boxes and no less than 35 mm for double corrugated boxes.

5.6 Bonding

5.6.1 Overlapping tongue width

For single corrugated boxes, the width should not be less than 20 mm. For double corrugated boxes, the width should not be less than 30 mm.

5.6.2 Bond strength

The bond strength is expressed as the peel rate. When tested according to the method in 6.7, no less than 70% of the bonded surface should be damaged during peeling.

5.7 Fold-resistant swing cover

When tested according to method 6.8, the face paper should not have any cracks, and the total length of the cracks in the lining paper should not be greater than 25% of the flap length.

5.8 Properties of fiberboard after processing

After corrugated fiberboard is processed into corrugated boxes, its thickness and edge

6.1 Appearance

Conduct visual inspection under natural light, at a distance of 1 m.

6.2 Dimensions and deviations

To measure the inside dimensions, stretch the box to form a square. After the two adjacent non-overlapping surfaces form a right angle, measure the length and width at the lap joint, 50 mm from the flap indentation. Measure the height as the distance between the inner flaps at the bottom and top. To measure the unfolded dimensions, unfold the box and fully flatten it. If it doesn't flatten, place a heavy object on top. After flattening, measure the length and width between the two adjacent vertical indentations.

Measure the height as the distance between the upper and lower corresponding flap indentations. To measure the outside dimensions, stretch the box to form a square. Fold the inner and outer flaps inward, sealing the box. Measure the length and width at the center of the top. Measure the height at the center of the box side, between the outer flaps at the bottom and top.

Using a measuring tool with an accuracy of at least 1 mm, measure the length, width, and height using the above method. Take the maximum deviation for each dimension, accurate to 1 mm.

6.3 Squareness

Stretch the box so that adjacent, non-overlapping surfaces form right angles. Fold the inner and outer flaps inward to seal the box. Measure the lengths of the top and bottom diagonals using a measuring tool with an accuracy of at least 1mm. Calculate the difference between the top and bottom diagonals. Take the maximum value, accurate to the nearest 1 mm.

6.4 Hole of box corner

Stretch the box so that its two adjacent, non-overlapping surfaces form right angles.

Fold the inner and outer flaps inward to seal the box. Measure the maximum dimension of the hole of box corner using a measuring tool with an accuracy of at least 1 mm. Take the maximum value, accurate to the nearest 1 mm.

6.5 Nailing

Stretch the box to form it. Using a measuring tool with an accuracy of at least 1 mm, measure the minimum distance between each pair of adjacent nails on the outer surface of the nail joint. Take the maximum value of these results, accurate to 1 mm. Also, using a measuring tool with an accuracy of at least 1 mm, measure the distance from the top end of the head nail to the centerline of the top indentation and the distance from the bottom end of the tail nail to the centerline of the bottom indentation, accurate to 1 mm.

6.6 Overlap tongue width

After disassembling the box along the joint, use a measuring tool with an accuracy of at least 1 mm to measure the distance from the edge of the lap joint to the lap joint pressure line. The minimum value is used as the lap joint width, accurate to 1 mm.

6.7 Bond strength

Use a knife to completely cut the bonded joint from the corrugated box. Peel the bond vertically along the bond line. After peeling, calculate the bond peel rate.

6.8 Fold-resistant swing cover

After pre-treating the sample according to GB/T 10739, expand the box to form the desired shape. Fold the flap inward 90°, then open and close it 180°. Repeat this cycle three times. Visually inspect the front and back paper for cracks. If cracks are present in the back paper, measure the length of all cracks with a measuring tool with an accuracy of at least 1 mm. Sum the lengths of all cracks to the nearest 1 mm. Calculate the percentage of the crack length to the total press line length.

6.9 Properties of processed corrugated fiberboard

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