Causes, countermeasures and effects on the quality of BOPP film slitting quality ---
two. Wrinkle (wrinkle, vertical wrinkle, cross wrinkle, line wrinkle)
Through many years, the BOPP industry has carried out a series of intensive and meticulous work on solving the problem of wrinkling. From the two aspects of process parameter screening and equipment adjustment and transformation, we have found a set of effective solutions and received very good results. effect,
1 The wrinkles near the core of the paper can not be stretched, which is largely related to the contact roller pressure of the slitter. It has been proved that when the contact roller pressure is increased, the wrinkles increase, and when the pressure is reduced, the wrinkles are reduced, and the air inside the film roll is reduced. The amount is increased, so that the gap between the membranes is increased to reduce friction, which is beneficial to reduce wrinkles;
2 When the winding pressure is small, the wrinkle is less, but the small pressure will cause the film roll to run off. Therefore, it is very important to set the pressure curve reasonably. When starting, set a small pressure, when it is easy to wrinkle. After a length of time has passed, the pressure should be increased rapidly to avoid the occurrence of deviation;
3 In the improvement of wrinkle, the control of winding tension should be considered. If only the winding pressure is considered, the initial pressure setting value will be very small. In case of special circumstances, the deceleration will cause deviation due to small pressure. Defects, so the tension curve setting is also very important, and the winding pressure and tension must be matched properly.
4 The pressure at the core of the paper cannot be reduced indefinitely. If it is too small, the inside of the film roll will be too loose, and the end face will appear star-shaped, causing the film to wrinkle. Therefore, it should be adjusted to the film roll when setting the pressure curve. The end face has neither a star shape and minimizes wrinkles;
Reasons, countermeasures and effects of BOPP film slitting quality ---
On the surface, slitting is the process of dividing a film of a width into several equal or unequal width products by a cutter. The slitting process is relatively simple, but often contains mystery in simplicity, in actual production. The slitting operation is a very important part in the production of BOPP film. The quality of the slitting will directly affect the quality level of the film and affect the quality of the user. Therefore, the quality of the slitting must not be underestimated in the film production process. . Only by fully recognizing the importance of the slitting process and fully grasping the basic essentials of slitting, can we minimize consumption and ensure the best product quality, in order to fully meet the needs of customers, and provide the most reliable product quality for BOPP film. Guarantee.
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