In the automatic production process of cardboard, almost all manufacturers want high strength and good stiffness of cardboard. However, they often counterproductive. Cardboard produced by many manufacturers is soft and has low strength, and customers are not satisfied and even fail to meet national standards. What are the reasons for these problems? This article analyzes such reasons and proposes solutions to the problems, and discusses them for reference by the majority of cardboard manufacturers.
The causes of the cardboard softness and solutions are as follows:
First, cardboard water is too high:
The solution is to reduce the moisture in the board. There are many factors that cause high water content in cardboard, and the situation is also more complicated. The specific analysis and solutions are as follows:
1. Cardboard production lines use more glue. Solution: Reduce the water in the glue.
2. A large amount of glue. There are two reasons for the large amount of glue applied: First, the gap between the gumming rolls is large. The solution is to adjust the slit of the applicator roll appropriately. Second, under the condition that the slits are not changed, the viscosity of the glue is too large, and the actual amount of glue will be relatively increased; the viscosity of the glue is small, and it is obviously smaller than the actual amount of glue. When the viscosity is too small, the amount of rubber to be coated is very small, and even the glue cannot be applied. Solution: Adjust the size of the slit of the rubber roller to ensure the proper amount of glue. In addition, when dispensing rubber, keep the size of the glue basically the same, when the viscosity of the glue varies greatly, the slit size should be adjusted at any time to ensure that the amount of glue is moderate.
3. The boot speed is too fast, the board stays in the drying tunnel for a short time, and the drying time is not enough. Solution: Control a reasonable boot speed according to the situation.
4. Steam pressure is low. Solution: Increase the vapor pressure; if you can not increase the vapor pressure, only reduce the startup speed.
5. The paper itself has high water content. Paper moisture in the same paper mill is not constant, and the water in the same batch of incoming paper will be high or low. Solution: Control the moisture of the paper. The water content of the paper is too high and should not be used.
6. The humidity of the air is high and the water does not evaporate. Solution: Only reduce the boot speed, extend the drying time, and reduce the water content of the board.
7. The width of the paperboard is so large that it is difficult to disperse moisture when producing large and wide cardboards. Solution: There is no good solution, but can only reduce the boot speed.
Second, corrugated forming is not good or the forming temperature is low, it will also cause the cardboard strength is not high.
Solution: Take appropriate measures to improve the forming temperature of the corrugation and ensure that the corrugated form is in good condition.
Third, the paper's own strength is not high.
Solution: Use high-strength paper.
Fourth, the adhesive strength is not enough.
Solution: Identify the cause of poor adhesion and ensure firm adhesion. For details, see separate article.
Fifth, the hardness of the film is not enough, causing the cardboard strength is not high. At present, most manufacturers use pure cornstarch, plus a certain amount of caustic soda, borax, their own plastic, their own use, the adhesive itself is not high hardness of the film, the role of improving the strength of the cardboard is not. Starch produced by different origins and different manufacturers has almost no difference in the film strength of the glue prepared with the same formulation; but if the same kind of starch is different, the adhesive strength of the formulated glue is different. In order to increase the strength of the film, the use of simple corn starch adhesive strength is not enough, but also can not produce high strength cardboard. Solution: The cardboard production line should use a special growth rate rubber powder.
In the automated production process of cardboard, the reasons for the softness and low strength of the paperboard are various, and the solution should also vary from one case to another. When a problem arises, it is first necessary to carefully analyze the problem, find out the cause, and successfully solve the problem. It should not simply be attributed to a certain reason.
Through the above analysis, we can see that as long as we understand what factors affect the strength of the board, in the production process, control these factors in the best condition, we can produce high-strength cardboard to meet the needs of market competition. (Xue Zhangli, Senior Engineer, Hefei Xuegong Adhesive Technology Co., Ltd.)
The causes of the cardboard softness and solutions are as follows:
First, cardboard water is too high:
The solution is to reduce the moisture in the board. There are many factors that cause high water content in cardboard, and the situation is also more complicated. The specific analysis and solutions are as follows:
1. Cardboard production lines use more glue. Solution: Reduce the water in the glue.
2. A large amount of glue. There are two reasons for the large amount of glue applied: First, the gap between the gumming rolls is large. The solution is to adjust the slit of the applicator roll appropriately. Second, under the condition that the slits are not changed, the viscosity of the glue is too large, and the actual amount of glue will be relatively increased; the viscosity of the glue is small, and it is obviously smaller than the actual amount of glue. When the viscosity is too small, the amount of rubber to be coated is very small, and even the glue cannot be applied. Solution: Adjust the size of the slit of the rubber roller to ensure the proper amount of glue. In addition, when dispensing rubber, keep the size of the glue basically the same, when the viscosity of the glue varies greatly, the slit size should be adjusted at any time to ensure that the amount of glue is moderate.
3. The boot speed is too fast, the board stays in the drying tunnel for a short time, and the drying time is not enough. Solution: Control a reasonable boot speed according to the situation.
4. Steam pressure is low. Solution: Increase the vapor pressure; if you can not increase the vapor pressure, only reduce the startup speed.
5. The paper itself has high water content. Paper moisture in the same paper mill is not constant, and the water in the same batch of incoming paper will be high or low. Solution: Control the moisture of the paper. The water content of the paper is too high and should not be used.
6. The humidity of the air is high and the water does not evaporate. Solution: Only reduce the boot speed, extend the drying time, and reduce the water content of the board.
7. The width of the paperboard is so large that it is difficult to disperse moisture when producing large and wide cardboards. Solution: There is no good solution, but can only reduce the boot speed.
Second, corrugated forming is not good or the forming temperature is low, it will also cause the cardboard strength is not high.
Solution: Take appropriate measures to improve the forming temperature of the corrugation and ensure that the corrugated form is in good condition.
Third, the paper's own strength is not high.
Solution: Use high-strength paper.
Fourth, the adhesive strength is not enough.
Solution: Identify the cause of poor adhesion and ensure firm adhesion. For details, see separate article.
Fifth, the hardness of the film is not enough, causing the cardboard strength is not high. At present, most manufacturers use pure cornstarch, plus a certain amount of caustic soda, borax, their own plastic, their own use, the adhesive itself is not high hardness of the film, the role of improving the strength of the cardboard is not. Starch produced by different origins and different manufacturers has almost no difference in the film strength of the glue prepared with the same formulation; but if the same kind of starch is different, the adhesive strength of the formulated glue is different. In order to increase the strength of the film, the use of simple corn starch adhesive strength is not enough, but also can not produce high strength cardboard. Solution: The cardboard production line should use a special growth rate rubber powder.
In the automated production process of cardboard, the reasons for the softness and low strength of the paperboard are various, and the solution should also vary from one case to another. When a problem arises, it is first necessary to carefully analyze the problem, find out the cause, and successfully solve the problem. It should not simply be attributed to a certain reason.
Through the above analysis, we can see that as long as we understand what factors affect the strength of the board, in the production process, control these factors in the best condition, we can produce high-strength cardboard to meet the needs of market competition. (Xue Zhangli, Senior Engineer, Hefei Xuegong Adhesive Technology Co., Ltd.)
Ningbo Ruichang Commodity Packaging Co.,Ltd , http://www.nbrcpackaging.com