Carton size management control classification

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)

Manufacturing length (width) = inner dimension length (width) + corrugated board thickness ÷ 2* layers of corrugated board

Manufacture of high dimensions = high inner dimensions + corrugated board thickness ÷ 2* layers of corrugated cardboard

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.

According to the requirements of design and development in the 9000 standard, the output of the new product design should be verified and confirmed. There are two methods to verify the output of the product: one is to measure and verify that its size meets the design's expected requirements; the other is to perform a physical load test. The second method is very practical and very simple. The first kind of measurement requires the mastery of scientific methods, otherwise the results of the measurements will be biased.

This is described in the SN/T 0262-93 Inspection Rules for Shipping Corrugated Paper Containers for Export Commodities. The cartons are supported and formed, and the angle between adjacent surfaces is 90°. The inner diameter ruler is used to measure the lap joint tongue at a distance of 50 mm from the box mouth. The length of the box and the width of the box shall be taken from the distance between the bottom of the box and the top of the box. But before measuring, there is a step that must be done: close the end of the flap, and support the cardboard box. The angle between the adjacent faces is 90°C, close to the gauge, and the inside of the box is pressed against the inner flap with a pressure plate. Open the top outside swing cover, place the wooden ruler horizontally on the inner swing cover, and then use the inner diameter ruler to measure the distance between the two faces in the length, width and height direction of the box at 50mm from the mouth of the box. If the height of the carton is small, the position from the first to the second spike distance can be measured because the two nails are relatively accurate in size. If the above test equipment is not available, the carton can be folded and shaped after measurement, leaning against the corner of the wall to ensure that the angle between the adjacent faces of the carton is 90°C. The author once encountered such a problem during the customer's visit. The customer's feedback was that the carton was not well formed and the dimensional deviation was large. After the visit, the original customer's inspector folded the carton and measured it directly at the press line. There are two errors in this. First, the carton is packed horizontally, in which the creases of the two pressure lines are aggravated, so that the cartons are often formed into a diamond shape after being folded. The cartons that are not properly folded can not guarantee the accuracy of measurement. Secondly, after the carton is formed, the shaking cover will support all four sides, especially in the pressure line, with the greatest error. In principle, the tongue should be 50mm from the pressure line or between the first and second spikes. The most accurate and reasonable position measurement.

The execution process is "fuse"

High-quality products are produced and not tested. Therefore, strict implementation of good processes is a prerequisite for ensuring product quality. The quality of the staff is a key factor. Carton molding process are: line longitudinal slitting lines, post-press slitting lines, die-cutting, manual touch line and so on. Hand touch is only seen in the smaller third-level plants. The quality of the touch-up line has a considerable relationship with the proficiency of the operators. The rest of the molding methods are relatively accurate, and the variation error is not large, especially now many It is computer-controlled, as long as employees take it seriously, the correct size input, the probability of a problem is very small.

After the remedy is "regret medicine"

If you are not afraid of 10,000, you will be afraid that if there is a problem in any link, it will be a serious non-conformity item. What should I do if something goes wrong?

First of all, we must immediately inform customers and carry out adequate coordination and communication. Once the product is produced and the customer's specific intentions are printed, it is impossible to resell others. The final result is only two: scrapped processing or customer concessions. The supply and demand sides of modern enterprises are all aiming at a win-win situation. If communication is sufficient, then by adopting certain remedial measures, it may be possible to avoid certain losses, but this is not advocated. The main remedial measures are:

n change the arrangement and manner of contents;

If the size of the n is slightly larger, padding or spacers should be added appropriately for filling.

If the size of the n is slightly smaller, properly crush the corrugated board.

(Note: This is extremely dangerous, and cartons that require strict compression resistance must never be done. The size of the next increase is also very limited.)

As the saying goes: Long carpenters, short blacksmiths, the principle of carton is also very small. However, as long as we are skilled in mastery of theory, scientific design, and strict implementation of technology, then why don't we just do simple things right?

Reprinted from: Industry Technology (Carton)