A Schematic Of The Structural Principles Of A Large Barrel Supporting The Entire Machine CI Flexible CI Type Flexographic Printing Machine

1. In a nutshell: What is Type CI?
CI type flexographic printing machine, also known as ``central Impression ''. Its core features only one-the entire machine around a large diameter of the central impression cylinder. Instead of being arranged in a straight line, all the color groups are evenly distributed around the circumference of the large drum, which resembles a sunflower petal. To understand the roller is to understand the entire structural logic of the CI machine.
2, Central impression cylinder: the whole machine the "sea fixing needle ''.
This drum is the soul component of the CI machine. Its diameter is much larger than ordinary unit type embossing rollers, and it is usually made surface smoothness high strength steel and precision ground. When moving paper, the printing material is always pressed against the surface of the drum. With each roller, the paper travels a fixed distance along its circumference.
The larger the diameter and circumference of the drum, the more printing units can be installed, and the larger the "span" between color groups, leaving room for a drying system. It can be said that the size of drum diameter directly determines the machine's color group capacity and paper path design.
3, Multiple printing units rotate around the drum.
Around the central drum, several printing units evenly distributed (commonly 6 or 8 colors). Each unit is a complete independent printing system, including mesh roller, scraper roll, plate roll and embossing roller four-piece set: mesh roller quantitative transfer of ink, scraper scrape off excess ink, plate roller contact with the substrate for transmission, embossing roller to ensure uniform pressure. All units share a central roller as a pressure base, each responsible for one color, and complete multicolor printing with a feeder.
4,. Paper Usage: Complete multicolored single-loop printing.
This is the most ingenious part of CI's structure. The printing material enters from the feeding end, affixes to the surface of the central drum, and passes through each printing unit arranged on the circumference in turn. After more than half a lap is completed, it is drawn from the output end. Because the paper is attached to the same drum throughout the printing process, there is no "separation repositioning" step between colors, and the printing base is naturally uniform, with no displacement due to intermediate tension or tension fluctuations.
5, One drum exchange for three major advantages.
** First, high printing accuracy. **All colors have a common reference plane, minimum cumulative error, stable lines, small characters, and accurate patterns.
** Second, tension is stable. **Thin films, shrinkage films, and other easily stretched materials are most afraid of tension fluctuations. CI type structure is the main solution for flexible packaging printing, with short paper path, full adhesion to paper cylinder and better tension control than unit type.
**Thirdly, multi-color compactness. ** Color groups are arranged along the circumference, and the elongation of the fuselage of 6 and 8 colors is not obvious, saving more factory space and ensuring more uniform drying distance between colors.
6, Structure determines trade-offs.
There is no perfect structure. The larger diameter and overall weight of the central drum result in higher construction and maintenance costs; the circular layout limits the thickness range of the substrate and machine adjustments are relatively cumbersome when material specifications change significantly; and paper products are less flexible and adaptable than modular systems. Therefore, CI type packaging is almost the only option for flexible packing films, whereas modular packaging is often more convenient for flexible small and medium batch scenarios such as labeling and paper boxes.
7, Summary
All the essence of CI flexographic printing machine is centered on this large cylinder, which is not only the basis of the die, but also the path of paper feeding, and a guarantee of the accuracy of overprint. Understanding the concept of ``support the whole machine '', we can master the selection and operation of CI machine core. Equipment is not absolutely good or bad, whether it is suitable for their own products is the only criterion.