1. Quality failure caused by bad machine of associated parts
When the printing roller shaft, pressing roller shaft, drive shaft, gear and important parts associated with the printing wear, loose, in the process of printing roller or roller will produce beating or sliding phenomenon, due to the pressure is unstable, the printing layout and cardboard contact is abnormal, cause cardboard printing surface paste or local marks. Through careful observation and analysis, find out the exact part of the fault, take corresponding measures to deal with, the wear, loose parts to repair, eliminate the fault phenomenon.
2. Quality failure caused by the improper adjustment of the pressure roller
If the position of the pressure roller is too high or too low, so that the contact with the corrugated board is too tight or too loose, there will be dirty, paste or local graphic unclear, should adjust the pressure roller to the appropriate position, make the gap between the pressure roller and the roller and the thickness of the board, to ensure that the printing layout, avoid the fault phenomenon.
3. Quality failure caused by bad ink roller
When the ink roller shaft head is loose, the ink roller roller body bending, deformation or surface damage, will also cause the layout of dirty, paste or local graphics are not clear. The cause should be found out, and the corresponding measures should be taken to deal with, so that the ink roller and the printing plate to maintain uniform and appropriate contact conditions, the damaged ink roller to be replaced, to eliminate the fault phenomenon.
4, the quality fault caused by uneven corrugated board thickness
If the surface of the formed corrugated board is damaged by the depression trace, the paper surface of the depression will also appear unclear imprinted quality defects, if the printing pressure to make up for this, it is easy to make the text, line layout paste quality problems. In order to avoid the layout paste, corrugated board in the process of stacking, handling, should pay attention to light moving, light putting, light pressure (to control the stacking height), do not use throwing, smashing, pressure and other bad production habits for handling.
5. Quality fault caused by the uneven thickness of the printing plate
When the thickness of the rubber plate is not uniform, the printing plate layout will appear in different height. The high layout is easy to paste, the low layout is easy to appear incomplete ink, resulting in unclear imprinting, in order to avoid the occurrence of this bad situation, can be used by sporadic plate making, the plate into several small pieces, the plate should use the same plate is made separately, so that its thickness difference is relatively small. If the rubber plate has been made, when there is a thickness difference, the multi-adhesive cloth layer can be made up in the back of the local thin printing plate, so that the whole printing plate remains basically the same thickness, to ensure the printing pressure and the layout of the ink.
6. Quality failure caused by improper color order
If the layout is full of pictures and pictures arranged in the first color group printing, when the corrugated board enters the next color group mechanism printing process, the printing of the first color group has large ink and slow drying speed, it is very easy to make the imprint transfer and cause the layout dirty. In order to prevent this problem, it is appropriate to arrange the small layout in the first color group printing, and arrange the large layout in the subsequent color group printing, so as to avoid the phenomenon of dirty version caused by imprint transfer.
Source: http://news.naliyin.com/
