I am an apprentice to four-color printing. I want to know how this printing machine works.

1. In the printing color sequence, try to arrange the whole page in the fourth group of printing on the spot to reduce the link of printed matter being bruised.

2. The fluidity of on-site printing ink should be greater than normal. In winter, red drying oil should be mixed with ink blending oil at a ratio of about 8%. This ink is used for printing coated paper and white cardboard. Ordinary paper printing ink can be prepared in normal proportion.

3. When replacing the new release paper still can't solve the problem, it is suggested to install 3-5 springs (along the circumferential direction) with a diameter of about 6mm on the delivery drum. If there is no spring suitable for I, it is possible to find some wires with a plastic sheath diameter of about 2mm instead, but the effect is slightly worse.

4. Stick a small piece of foam plastic with a thickness of 5 mm on the non-solid part of the printed matter and the corresponding part in contact with the delivery drum to increase the distance between the delivery drum and the printed matter. If the field edition is arranged in the first few groups, the thickness of foam must be controlled within the range that does not affect overprinter.

5. When Roland four-color printing is used for printing, the printing plates are arranged in one group or two groups according to the facts, and the middle paper feeding tooth row will also get dirty printed matter due to ink accumulation. As long as it is cleaned frequently, the problem can be solved.

6. Some Roland machines have only a few delivery wheels on the delivery drum. If you often print coated paper, you'd better refer to the delivery drum of domestic 08 machine, which is simpler.

In the printing process, pay attention to the above points, which can basically solve the problem of bumping when printing on the spot in a large area.