Reasons, countermeasures and effects of BOPP film slitting quality ---
eleven. Width deviation is too large
The width of the film roll is limited by the gap of the sipe roll. The actual slit width will deviate from the width required for the order, but the deviation should be controlled within the tolerance range of ±2mm required by the national standard. The so-called width deviation Large, that is, the actual width of the film roll exceeds the requirements of internal control standards or customer standards.
Not all products have a tolerance of ±2mm, and some customers can only take deviations from the film width, such as the Pd film of Kunshan Zhangpu, the LL film of Shanghai Zhicheng, the PL film of Beijing Amcor, etc. It is required to adjust the film width.
Domestic cutting machine development status and outlets ---
1. Not rigorous in the manufacturing process
Tolerance control in the mechanical manufacturing process is not precise enough, and the surface is rough, especially in the matching electroplating industry, which is shoddy. There is a defect in the dynamic balance of the roller for cutting the Chinese-made equipment at one time. The lag of the related industry, the rubber coated by the roller has far less wear resistance and anti-aging than the foreign products. The bearings used seem to use well-known foreign brands, but the counterfeit and shoddy floods the domestic bearing market. Even when the real goods are purchased, the precision is far lower than the precision used by foreign slitting machines.
In the entire production process of a slitting machine, there is no guarantee of production process. At present, most of the slitting machines produced in China are completed by a number of outsourcing units, and the quality of their production is even more difficult to guarantee. In addition, the metal materials used and the heat treatment process are not rigorous enough, resulting in many problems in the use of a slitting machine. It has seriously affected the share of a slitting machine in the domestic market. The secondary and tertiary slitting machines have fewer problems than the one slitting machine, because the parts of the secondary and tertiary slitting machines are completed by the slitting machine manufacturer, and the dynamic balancing machine used is in a narrow range. It can accurately control the unbalanced grams, and the industrial difficulty coefficient of manufacturing is reduced. Its selling price is far lower than that of foreign products. Therefore, the proportion of domestically produced slitting machines in the domestic slitting machine market getting bigger.
Slitting machine parts ---
2. Attenuation and tension compensation of the tension of the rewinding and unwinding: It is generally believed that maintaining the constant tension of the aluminum foil during the rewinding and unwinding of the aluminum foil is beneficial to the apparent quality of the finished aluminum foil, but it is not. The best method is to increase the tension of the aluminum foil according to a certain rule as the diameter of the coil increases, and the smaller the diameter, the lower the tension value. There are automatic tension control and manual tension control during the slitting operation. The automatic tension control system is the leading set tension attenuation value, which is maintained throughout the winding process. The manual tension control requires the operator to continuously adjust the diameter of the master roll to meet the tension required for the aluminum foil during operation. When setting the automatic tension operation, set the initial tension before setting the tension attenuation value. Taking the setting of the slitting and unwinding attenuation value as an example, the setting principle is that the aluminum foil tension attenuation value (%) is equal to the tension at the end of winding of the aluminum foil minus the initial tension and then divided by the initial tension. Multiply by 100%. When setting the automatic tension value of the unwinding, it should not be too large, otherwise the aluminum foil winding surface has a large hardness and is prone to warping. But the tension should not be too small, too small and easy to cause the rewinding body to be too loose, and the winding is not neatly running. Therefore, the quality of the rewinding and unwinding during the aluminum foil slitting operation is mainly affected by the change of the tension of the aluminum foil. It can be seen that the mastery of the retracting and unwinding control system is the key to affecting the quality.
3. The change of speed during slitting affects the change of tension: When the speed is increased or decelerated, the speed of the main motor changes. Firstly, it causes the instantaneous change of the tension of the unwinding traction to the winding section of the aluminum foil, and it is necessary to slightly vibrate the aluminum foil after a period of time to gradually stabilize the tension. The instability of this tension is manifested in the fact that the finished roll is not well-wound, and the end face has unevenness, which affects the quality of the product.
Zhengzhou EAST IMPORT AND EXPORT co., ltd . ( a goulian group of company) a manufacturer and exporter for all kind of packaging machinery , like bopp tape coating machines, bopp tape slitting machines. Bopp tape core cutter, bopp tape core loader etc