Causes, countermeasures and effects on the quality of BOPP film slitting quality ---
two. Wrinkle (wrinkle, vertical wrinkle, cross wrinkle, line wrinkle)
1. The effect of wrinkles on the quality of use
BOPP film is commonly known as "cellophane", which reflects the film's high stiffness, high transparency and good gloss. The film is wrinkled, which means that the flatness of the film is damaged to a certain extent. This is not allowed for any film. Not only will it affect the appearance of deep-processed products, but also cause quality defects in use, such as lack of coating, lack of printing, and so on. 2. Causes and countermeasures of wrinkles
The wrinkles caused by the slitting of the film have various forms such as wrinkles, longitudinal wrinkles, cross wrinkles, and line wrinkles, and the causes are also different, as follows:
(1) Wrinkle: also known as bottom wrinkle, initial wrinkle, etc., is the wrinkle appearing in the section of the original winding film of the paper core. Since the wrinkle is mostly irregular wrinkles, the user generally uses the film to wrinkle. Disposal. The degree of wrinkling is an important indicator reflecting the level of cutting technology of a BOPP film company. The film produced by different companies has a wrinkle length ranging from a few meters, tens of meters to several hundred meters, and the more serious the wrinkles, the more The greater the losses caused by users, therefore, each film company is committed to improving the research of slitting and 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,
Slitting machine operation guide ---
4 operational requirements
4.2.1 When loading paper, it is necessary to standardize the operation. If there are products that do not meet the quality requirements, the products should be picked out and clearly marked, and feedback should be sent to the squad leader.
4.2.2 Before the official production, the crew must pass the start-up information to each other, and it is not allowed to stack debris that interferes with the operation around the machine. The captain (blocking vehicle) shall compare the trial production sample with the standard proof, and self-check the product size specification. After confirming the pass, sign the first proof, and the sample will be retained until the end of the project.
4.2.3 When cutting, it is necessary to see the product specifications and determine in advance whether the size of the slitting knife meets the product quality requirements.
4.2.4 Each group of products must be self-tested, and the quality requirements and production process control shall be carried out according to the “Product Printing Process Card”.
4.2.5 After each group of products has been cut, the product label is affixed to the self-test and the production record is filled. The products to be re-rolled are processed on the shift; the items to be treated or scrapped are labeled and transferred to the treated area or waste as required. Area. The label of each product must clearly and accurately indicate the current product status, quality or problems.
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