I am a four-color machine printing apprentice. I would like to know how the printing machine operates?

1. In terms of printing color sequence, try to place the full page in the fourth group of prints to reduce the chance of the prints being damaged.

2. The fluidity of solid printing ink should be greater than normal. In winter, use a combination of red drying oil and ink-adjusting oil, with a proportion of about 8%. This ink is used for printing coated paper and white cardboard. Ink for printing on ordinary paper can be prepared in normal proportions.

3. When replacing the new release paper still does not solve the problem, it is recommended to install 3 to 5 springs with a diameter of about 6mm (in the circumferential direction) on the take-up roller. If there are no suitable springs, find a few with plastic coverings. A wire with a diameter of about 2mm can also be substituted, but the effect is slightly worse.

4. Glue a 5mm thick piece of foam plastic to the corresponding part of the non-solid part of the printed product that is in contact with the delivery roller to increase the distance between the delivery roller and the printed product. If the field version is arranged in the first few groups, the thickness of the foam must be controlled within a range that does not affect overprinting.

5. When printing with a Manroland four-color machine, the solid plates should be arranged in one or two groups. The paper transmission tooth row in the middle will also stain the printed matter due to ink accumulation. As long as it is cleaned frequently, the problem can be solved.

6. Some Manroland machines only have a few take-up rollers on the take-up roller. If you often print coated paper, it is best to modify it by referring to the take-up roller of the domestic 08 machine, which is also easier to do.

During the printing process, paying attention to the above points can basically solve the problem of bruises when printing large-area field prints