Talking about the causes and countermeasures of bulging and damaged cartons

There are two main problems in the use of cartons:

1. Fat bag or swollen bag;

2. Damage to the carton.

We analyze the causes of the problem as follows:

1. The cause of the problem

Fat bag or bulge bag

1. Improper selection of flute type

The height of the A tile is the highest. Although the same paper has good vertical pressure performance, it is not as good as the B and C types. After the A-watt carton is loaded with the product, the carton will be subjected to horizontal and vertical vibration during transportation, and the repeated impact between the packaging and the carton will make the wall of the carton thinner and appear fat or bulging.

2. The impact of stacking finished shovel plates

When the products are stacked in the finished product warehouse, they usually pile up very high, usually two shovel plates are stacked high. During the stacking process of cartons, the strength change of cartons, especially bottom cartons, is a "creep" process, which is characterized by a relatively stable load acting on the cartons for a considerable period of time, and the cartons will produce continuous bending deformation under static load. If the static pressure is maintained for a long time, the cartons will collapse and be damaged. Therefore, the cartons of the lowest layer stacked on the shovel will often swell and part of them will be crushed. When the carton is under vertical pressure, the center of the box surface deforms the most, and the crease after crushing appears like a parabolic bulge. The test proves that when the corrugated box is compressed, the strength at the four corners is the best, and the strength at the midpoint of the transverse edge is the worst. Therefore, the feet of the upper shovel are directly pressed in the middle of the carton, causing a concentrated load in the middle of the carton, which will cause the carton to break or be permanently deformed. Also, because the gap between the shovel plates is too wide, the corners of the cartons fall in, which will cause the cartons to be fat or swollen.

3. The exact size of the box height has not been determined

The carton height of carbonated beverage boxes and water tanks is generally determined to be the bottle height of the contents bottle plus about 2mm. When the cartons are stacked, they bear static load for a long time, and are subject to shock, vibration, and bumps during transportation, which causes the thickness of the cartons The thinness increases a part of the height, making the box height larger than the bottle height, thus making the fat or bulging of the carton more obvious.

A large number of damages to cartons are mainly due to the following factors:

1. The design of the carton body size is unreasonable

The length, width, and height of the carton have a greater relationship with the damage of the carton. The size of the carton is generally determined according to the number of bottles to be packed and the height of the bottles. The box length is the number of bottles in the longitudinal direction × the diameter of the bottles, the box width is the number of bottles in the width direction × the diameter of the bottles, and the box height is basically the bottle height. The perimeter of the four sides of the box is equivalent to the entire side wall supporting the pressure load of the carton. Generally, the longer the perimeter, the higher the compressive strength, but this increase is not proportional. If the perimeter of the four sides is too large, that is, the number of bottles in the contents is relatively large, the gross weight of the whole box will be large, and the requirements on the carton will also be high. It needs to have higher compressive strength and burst resistance to ensure the use performance of the carton, otherwise , The cartons are more prone to breakage during the circulation process. On the market, the 596mL×24-bottle pure water tank is the most damaged among all cartons, because its gross weight is relatively large, and it is also a single-tile carton, which is prone to damage during the circulation process.

When the length and width of the carton are the same, the height has a greater influence on the compressive strength of the empty carton. When the perimeter of the four sides of the carton remains unchanged, as the height of the carton increases, the compressive strength decreases by about 20%.

2. The thickness of corrugated cardboard does not meet the requirements

As the corrugated roller is worn during use, the thickness of the corrugated cardboard does not meet the specified requirements, so that the compressive strength of the carton is low, and the strength of the carton is also reduced.

3. Corrugated deformation of carton

The cardboard that produces corrugated deformation is soft, with low plane strength and low rigidity. Corrugated boxes made of such cardboard have low compressive strength and puncture strength. Because the shape of the corrugated board is directly related to the compressive strength of the corrugated board. Corrugated shapes are generally divided into U-shaped, V-shaped, and UV-shaped. U-shape has good stretchability, elasticity and high energy absorption. Within the elastic limit, it can still return to its original state after the pressure is removed, but the strength of the flat compression is not high due to the unstable point of the arc. V type has little contact with the paper surface, poor adhesion, and easy peeling. With the help of the combined force of the two diagonal lines, the stiffness is good and the flat compressing strength is greater. However, if the external force exceeds the pressure limit it can withstand, the flute shape is destroyed and cannot be restored to its original shape after the pressure is removed. The UV type takes the advantages of the above two flute types, with higher compressive strength, better elasticity and elastic recovery ability, and is an ideal flute type.

4. The number of cardboard layers of the carton is unreasonably designed

The unreasonable design of the number of cardboard layers will increase the damage rate of the outer packaging carton. Therefore, the number of cardboard layers used in the carton should be considered according to the weight, nature, stacking height, storage and transportation conditions, storage time and other factors of the packaged goods.

5. The carton has poor bonding strength

To judge the adhesion of the carton, just tear off the adhesive surface by hand. If the original paper surface is found to be peeled off, it means that the paper is well-adhered; if there is no tearing paper fiber or white in the lugfeng adhesive. Powdery, it means that it is fake stick, which will cause the carton's compressive strength to be low, and affect the strength of the entire carton. The bonding strength of the carton is related to the grade of the paper, the preparation of the adhesive, and the manufacturing equipment and process operations.

6. The printing design of the carton is unreasonable

The corrugated shape and structure of corrugated cardboard determine the bearing pressure of corrugated cardboard. Printing will cause certain damage to the corrugated board. The size of the pressure and the size of the bearing area are a major factor affecting the compressive strength of the carton. If the printing pressure is too high, it is easy to crush the corrugation and reduce the corrugation height. Especially when printing at the press line, in order to perform forced and clear printing at the press line, the entire cardboard will be crushed and the compressive strength of the carton will be greatly reduced. Therefore, try to avoid printing here. When the carton is full or surrounded by graphics and text, in addition to the pressing roller on the corrugated cardboard, the ink also infiltrates the paper surface, which in turn reduces the compressive strength of the carton. When a general carton is fully printed, its compressive strength drops by about 40%.

7. The cartons' paper regulations are unreasonable and the paper does not meet the requirements

In the past, goods were mainly handled by humans in the circulation process, and the storage conditions were poor, and they were mainly in bulk form. Therefore, the burst resistance and puncture degree were used as the main criteria to measure the strength of the carton. With the mechanization and containerization of transportation and circulation methods, the compressive strength and stacking strength of cartons have become the main indicators to measure the performance of cartons. When designing cartons, the compressive strength that the cartons can withstand is used as the condition and the stacking strength is inspected. Code strength.

If the minimum compressive strength is not considered in the design and determination of the carton paper, the carton paper cannot reach the required compressive strength, which will cause a lot of damage to the carton. There are clear regulations on the paper quantitative of each carton. When the supply is changed, the paper can only be high-allocated, not low-allocated.

8. Impact of transportation

Many of the reasons for the damage of commodities in the circulation process are caused by improper transportation or loading. Although some product packaging protection measures have reached high requirements, damage will still occur. In addition to the unreasonable packaging design, the reason is mainly related to the choice of transportation means and methods. The impact of transportation on the compressive strength of cartons is mainly impact, vibration, and bumps. Due to the large number of transportation links, the impact on the cartons is greater, coupled with the backward transportation method, the savage loading and unloading of the movers, and the random stepping and falling, which are easy to cause damage.

9. Poor management of the seller’s warehouse

Due to the short aging of carton performance, the compressive strength of corrugated boxes in circulation will decrease with the extension of storage time.

In addition, the humidity in the warehouse environment has a great influence on the strength of cartons. The carton has the function of draining and absorbing the moisture in the environment. The relative humidity in the warehouse environment is very high, and the strength of corrugated boxes will plummet.

Distributors often pile up goods very high due to small storage locations, and some even pile goods on the roof, which has a great impact on the strength of cartons. If the compressive strength of the carton measured by the standard method is 100%, then 70% of the static load is added to the carton, and the carton will collapse in one day; if the static load is 60%, the carton can withstand 3 weeks; add 50 When %, it can withstand 10 weeks; when it increases by 40%, it can withstand more than one year. It can be seen from this that if the stack is too high, the damage to the cartons will be fatal.

2. Measures to solve the problem

Measures to solve the fat bag or bulge of the carton:

1. Determine the corrugated type of the carton as the appropriate corrugated type

Among Type A, Type C, and Type B corrugations, Type B has the lowest corrugation height. Although the vertical pressure resistance is poor, the plane pressure is the best. After the carton adopts B-type corrugated, although the compressive strength of the empty carton will be reduced, the contents are self-supporting and can bear part of the stacking weight when stacked, so the stacking effect of the product is also good. In actual production, different flute types can be selected according to specific conditions.

2. Improve the storage conditions of products in the warehouse

If the warehouse location allows, try not to stack two shovel boards as high as possible. If it is necessary to stack two shovel boards high, in order to prevent the load concentration when the finished products are stacked, a corrugated cardboard can be inserted in the middle of the stack or a flat shovel board can be used.

3. Determine the exact carton size

In order to reduce the fat bag or bulging phenomenon and reflect a good stacking effect, we set the height of the carton box to be the same as the bottle height, especially for carbonated beverage cartons and pure water tanks with relatively high box height.

Measures to solve the damaged carton:

1. Reasonably designed carton size

When designing a carton, in addition to considering how to save materials with a certain volume, it should also consider the restrictions on the size and weight of a single carton in the market circulation, sales habits, ergonomics, and the convenience and reasonableness of the internal arrangement of the goods. Sex and so on. According to the principle of ergonomics, the appropriate carton dimensions will not cause fatigue and injury to the human body. Heavy carton packaging will affect the transportation efficiency and increase the probability of damage. According to international trade practice, the weight limit of a package carton is 20kg. In actual sales, for the same commodity, different packaging methods have different degrees of popularity in the market. Therefore, when designing a carton, you should try to determine the size of the packaging according to sales habits.

Therefore, in the carton design process, various factors should be considered comprehensively, and the compressive strength of the carton should be improved without increasing the cost or affecting its packaging efficiency. And after fully understanding the characteristics of the contents, determine the reasonable size of the carton.

2. Corrugated cardboard reaches the required thickness

The thickness of corrugated cardboard has a great influence on the compressive strength of the carton. During the production process, the corrugated rollers are severely worn, causing the thickness of the corrugated cardboard to decrease, and the compressive strength of the carton also decreases, resulting in an increase in the damage rate of the carton.

3. Reduce corrugated deformation

First of all, it is necessary to control the quality of the base paper, especially the physical indicators such as the ring compressive strength and moisture of the corrugated core paper. Secondly, the corrugated board process is researched, and the corrugation deformation caused by factors such as the wear of the corrugating roller and the insufficient pressure between the corrugating rollers is changed. Third, improve the carton manufacturing process, adjust the gap of the paper feeding roller of the carton machine, and change the carton printing to flexographic printing to reduce the deformation of the corrugation. At the same time, pay attention to the transportation of cartons, and try to use vans to transport cartons to reduce corrugated deformation caused by tarpaulin and rope binding and the stepping of stevedores.

4. Design the appropriate number of corrugated cardboard layers

Corrugated cardboard can be divided into single-layer, three-layer, five-layer, and seven-layer according to the number of layers of its material. As the number of layers increases, it has higher compressive strength and stacking strength. Therefore, the choice can be made according to the characteristics of the product, environmental parameters and consumer requirements.

5. Strengthen the control of the peeling strength of corrugated boxes

The bonding strength of the corrugated core paper and the face paper or the inner paper of the carton can be controlled by a testing instrument. If the peel strength does not meet the standard requirements, find the reason. Suppliers are required to strengthen the inspection of carton raw materials, and the tightness and moisture content of the paper must meet the relevant national standards. And by improving the quality of adhesives, improving equipment, etc. to achieve the peel strength required by the national standard.

6. Reasonable design of carton pattern

Carton boxes should try to avoid full-page printing and horizontal strip printing, especially the horizontal printing in the center of the box surface, because its function is the same as the horizontal pressure line, and the printing pressure will crush the corrugation. When designing the printing on the carton surface, it is necessary to reduce the number of color registrations as much as possible. Generally, after single-color printing, the compressive strength of the carton is reduced by 6%-12%, and after three-color printing, it will be reduced by 17%-20%.

7. Determine the appropriate paper regulations

In the specific carton paper design process, appropriate base paper should be selected appropriately. The quality of raw materials is the main factor that determines the compressive strength of corrugated boxes. Generally, the compressive strength of corrugated boxes is directly proportional to the basis weight, tightness, stiffness, and transverse ring compressive strength of the base paper; it is inversely proportional to the moisture content. In addition, the influence of the appearance quality of the base paper on the compressive strength of the carton cannot be ignored.

Therefore, to ensure sufficient compressive strength, first of all, we must choose high-quality raw materials. But when designing the paper for the carton, don't blindly increase the grammage and grade of the paper, and increase the total grammage of the cardboard. In fact, the compressive strength of corrugated boxes depends on the combined effect of the ring compressive strength of the face paper and the corrugated core paper. Corrugated core paper has a greater impact on strength, so regardless of strength or economic considerations, the effect of improving corrugated core paper grade performance is better than improving facial paper grade, and it is much more economical. You can go to the supplier to check on the spot, take samples of the base paper, and measure a series of indicators of the base paper to control the paper used in the cartons, prevent cutting corners, and shoddy.

8. Improve transportation

Reduce the number of transportation and handling of goods, use the method of nearby delivery, improve the handling method (shovel handling is recommended); educate porters, improve their quality awareness, and prevent rough loading and unloading; pay attention to rain and moisture during loading and transportation , The binding cannot be too tight and so on.

9. Strengthen the management of the dealer's warehouse

The goods sold should follow the first-in-first-out principle, the number of stacking layers should not be too high, the warehouse should not be too humid, and it should be kept dry and ventilated.