The most important use of corrugated boxes is packaged goods, but if there is a size deviation in the carton, it is equivalent to making a fatal mistake. Many people in the industry will feel that the carton size management control is the most basic and the simplest, but as a corrugated box user often does not think so, the size problem directly determines the value of the carton. The right size customer will accept the use. Improper size, no matter how good the other projects are, it will not help. However, it is a very systematic task to truly manage and control the size of cartons. Therefore, it is the most economical and scientific management to deal with simple things once and for all.
Good size is the "foundation stone"
There are three forms of corrugated box size: outer size, manufacturing size, and inner size. All three forms are composed of the length, width and height of the carton. Therefore, the specific expression is divided into the width of the foreign minister, the length and width of the interior, and the length, breadth and height of the manufacture. The outer size is the size of the volume taken from the outside of the corrugated box, which is generally used as the basis for the calculation of freight and the labeling on the outside of the carton. The inner size is the distance from the inside to the surface measured after the corrugated box is supported and shaped. The inner dimension is determined according to the volume of the contents. Generally, the inner size is slightly larger than the volume of the contents. The manufacturing size is the size of the production process converted from the size of the carton, and the production operation is generally performed according to the production size and the adjustment of the pressure line.
The relationship among outer size, inner size, and manufacturing size: (Example of 0201 carton)
Outer dimension length (width) = inner dimension length (width) + corrugated board thickness * number of layers of corrugated board (2 layers)
Outer dimension height = inner dimension height + corrugated board thickness * number of layers of corrugated board (includes 4 layers of inner and outer flaps)
Manufactured in Long (Width) = Inner Length (Width) + Corrugated Board Thickness ÷ 2* Number of Corrugated Boards Manufactured Dimensions High = Inner Dimensions High + Corrugated Cardboard Thickness ÷ 2* Corrugated Cardboard Dimensions
There is also a comprehensive size in the national standard. The overall size of the carton is the sum of the length, width and height of the carton. In the above three dimensions, the manufacturing size is relatively flexible, and it is changed at any time according to the thickness of different corrugated cardboard, different pressure line molding equipment, and different molding processes, so grasping the manufacturing size is the first to control the size of the carton. step. The same is true for shaped cartons. Regardless of the number of layers of corrugated board, the total thickness of these corrugated cardboards must be added to the inner dimensions, which is the outer dimensions of the cartons.
Scientific design is "vaccination"
Designing the size of a corrugated carton requires first the design of the inner dimensions. Because the inner size is relatively easy to determine, it is determined by the actual measurement of the product or the outer dimensions calculated by the physical combination. The discharge of contents should be as space-saving as possible, and reasonable consideration should be given to the factors of support. From the mechanics point of view, if the contents share a part of the supporting force, the requirements of the carton compressive index can be appropriately reduced. Therefore, it means cost reduction and profit acquisition. If the contents are paper trays, consider the direction of the cassette's strands, as the longitudinal filaments are better than the transverse filaments.
In the forming process of the corrugated box, the corrugated board is pressed to make the corrugated board to be well bent, and at the same time, the pressure line breaks the structure of the corrugated board so that the inner paper shrinks and the front paper extends. The amount of stretching is directly related to the thickness of the board and the way the lines are pressed. The thicker the cardboard, the larger the stretch value, the wider the pressure line, the greater the stretch value. However, no matter whether it is a two-line, three-line or five-wire type corrugated box, the protruding part of the bottom line of the pressure roller will squeeze the compression part of the corrugated board into the center position of the corrugated board. Therefore, the inner size of the corrugated box is slightly shorter than the distance between the line and the pressure line when the corrugated box is unfolded. In this case, the shortened portion is added as a correction value, which is closely related to the thickness of the corrugated cardboard.
The most common carton boxes are usually butt-sealed in order to protect the contents. This requires that the flap size of the carton must be calculated accurately, and there should be no gap after the docking, nor can the flap stack be overlapped. In principle, the theoretical width of the swing cover width should be one-half of the box width. However, because the inner and outer flaps are on the same pressure line, the inner flap is folded to support the outer flap, and the outer flap must have a certain gap at the butt joint. Therefore, it is very important to calculate the correction value of the dimensions of the outer flap width. This correction value is generally half of the thickness of the pressed cardboard, but the different pressure line equipment caused by the cardboard surface, the paper is not the same as the expansion and contraction, so it is best to be determined through actual measurements.
In short, in the structural design of corrugated boxes, it is necessary to determine according to the manufacturing equipment used and the different production processes and the types and properties of the different types of corrugated cardboard and interior products used. Only the design corrugated boxes are mastered. The corrugated boxes that protect the goods and beautify the products can be manufactured only after the contents of the structure and dimensions are relevant.
Source: Corrugated box industry