Generally small and medium-sized packaging, such as beer, beverages, fruit and other food cartons, more and more products using white paper for color printing. The preprinting process of the carton is much better than the quality of printing directly with corrugated cardboard. However, as with other printing processes, it is also not possible to print various cartons or cartons and paper bag products with an offset or letterpress printer. Avoid some quality problems. Therefore, correct understanding and understanding of several fault phenomena in the printing process, and good printing operations and process technology, in order to better improve production efficiency and product quality.
First, the problem of ink stick caused by unsatisfied printing pressure:
When the bearing of the blanket cylinder is seriously worn, due to excessive roller separation, the surface of the cylinder is caused to slide and cause ink mark marks. This is a situation; the second case is due to the use of a hard lining, embossing In the process, ink sticks are caused by the sliding phenomenon; in the third case, the roller gears are worn badly, and the center distance of the drum is too large, so that the backlash of the gears is too large, so that the gears vibrate after the drums are pressurized, and the sliding friction occurs on the drum surface. The fourth situation is that the pressure between the plate cylinder and the blanket cylinder is too large, so that the blanket is squeezed to form a large frictional slide, which causes the longitudinal deformation of the screen surface to expand and cause ink bars. The above situation shall be achieved by replacing the roller bearing, adjusting the characteristics of the packing material, and reducing the center distance of the roller, so that the meshing backlash of the gear is less than 0.1mm; according to the specification of the equipment, the thickness of the packing shall be set to avoid the occurrence of excessive pressure. In order to prevent the occurrence of ink bars