Reasons, countermeasures and effects of BOPP film slitting quality ---
Seven. Sharp edge
The curling occurs at the edge of the film winding, which causes the curling. The reason is that the edge of the thick film is curled up and the edge part is lifted up; the second is that the winding is too tight, and the tension can be shortened by slitting. Speed ??to improve the resulting edge curling phenomenon; third, the cutter is too blunt, and the stretching phenomenon occurs at the slit when slitting, causing the edge of the film roll to be turned outwards after winding to cause the curling edge, and the cutting should be replaced in time. The knife can avoid the occurrence of the curling problem; the fourth is that the tool is not installed correctly, such as the blade is close to the edge of the sipe and the blade is passivated. Cutting with a round knife can improve the curling of the film roll.
In the use of the unwinding process, there will be different degrees of side-floating in the unwinding process, and it is impossible to track the alignment with the electric eye, which directly affects the use effect. Therefore, it is necessary to change the product with the curled edge.
Domestic cutting machine development status and outlets ---
3. Lack of insight into the characteristics of different materials at the time of slitting, distinguishing between control systems and structures
Everyone knows that the physical properties of different materials are inconsistent. Some materials are smooth and firm. Some materials are very soft and soft, and the physical properties of the same material with different thicknesses are not the same. Among the slitting machines, the structure is also different, and there is a lack of changes in the control system due to its structural changes. The difference is rarely studied. In particular, the change in the difference in the control curve is even less known, and its mature control system software is still very few in China. Although some people have tried the application of a slitter control software, the chances of success are very low. Most of them are characterized by “headaches and pains.” Although our company has experienced 7-8 years of hard work, Some experience has been gained and the control system is becoming more mature, but there is still a certain gap compared with the materials covered by well-known foreign brands.
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