Tension information detection method
(1) Tension sensor detection method: It is a method of detecting the tension directly, closely combined with the machine, and without moving parts. Usually two sensors are paired and mounted on the end shafts on both sides of the detection guide roller.
(2) Roll diameter calculation type detection method: It uses the proximity switch installed at the reel to detect the rotation speed of the reel. Because the reel rotates once, the winding diameter will change twice the thickness of the material.
The current diameter of the reel is obtained by cumulative calculation by the initial value of the reel diameter and the material thickness, and the change of the corresponding reel diameter reflects the change of the actual tension value.
(3) Floating roller position detection mode: It uses the cylinder attached to the slitter to connect the floating roller to drive the angular displacement sensor to detect the tension change. When the tension is stable, the tension on the material is balanced with the cylinder force, so that the floating roller is in the center position. When the tension changes, the balance between the tension and the cylinder force is broken, and the position of the floating roller will rise or fall. At this time, the swing lever will rotate around a point and drive the floating roller angular displacement sensor to rotate together.
(4) Floating roller position + tension sensor combined tension detection mode: It can simultaneously detect the floating roller position signal output by the floating roller angular displacement sensor and the tension signal output by the tension sensor, thereby providing higher precision tension control to the system. .
Causes, countermeasures and effects on the quality of BOPP film slitting quality ---
(iv) Effect of film roll tightness on product quality
2. The volume is too loose:
1 Shift: Due to the looseness of the winding, the film roll is easy to move in series and shifts. If the degree is serious, it cannot be used.
2 Core-pulling: Due to the looseness of the winding, the film roll has serious end face misalignment near the paper tube during the loading or unloading or use process, commonly known as “core pulling”, which affects the appearance and use effect of the product.
3 The film wrinkles produced by the loosening of the rolls and the pit lines (stars) formed by the tightness of the inner pines affect the appearance quality and the use effect of the products to some extent.
4 Face wrinkles: Due to the looseness of the winding, the point support force of the end face of the film roll during the movement is reduced, and the fish scale-like end face wrinkles are easily generated.
5 Eccentricity: If the winding is too loose, the film roll will be eccentric (elliptical), and the unwinding tension will be uneven during the unwinding process, which will affect the use effect, especially the printing overprinting effect.
Reasons, countermeasures and effects of BOPP film slitting quality ---
ten. Color circle
The color circle is caused by a certain degree of contamination inside or outside the film, which causes the quality of the color circle on the end face of the film roll after slitting and winding. Membrane surface pollution sources come from two aspects. One is the film-forming process. The color circles generated in the front part of the film, such as raw materials, feeding systems, extrusion systems, and die flow channels, generally cause pollution to the inside of the film (core layer). Some color-circle products can clearly observe a large amount of fish-eye impurities in the film. The color circles generated in the film-forming stage and the slitting process mainly cause pollution to the outside (surface) of the film, but whether it is internal or external pollution, It is impossible to remove the impurities from the contaminated film and restore the original appearance. The product with serious color circle has low transparency, the film color is different from the normal product, and it can not be used at all. It can only be reduced to other external treatments, while the products with slight color circles are It has little effect on the transparency of the product and does not affect the use effect of the single film. However, due to the inconspicuous appearance of the color circle product, the “selling phase” is poor, which has a great influence on the image of the German brand. It is not suitable for direct delivery. Secondary processing. If the color circle is caused by external dust pollution factors, the dust will be adsorbed on the surface of the film, resulting in poor quality of heat sealing and poor laser compression.
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