Debugging and Maintenance of Rubber Rollers

Debugging and proper use

　　Regardless of the type or model of the printing machine, after the new equipment is installed, the printing rubber roller must first be installed by technicians and the lead machine. The height of the rubber roller must be adjusted reasonably, and it must be in close contact with the ink roller and the printing plate; both are indispensable. Those engaged in printing know that the height of the relief plate is 3.14mm, which is consistent with the height of the type, while the PS plate is relatively lower at 1.2mm, so when installing and adjusting the rubber roller, one must be aware of this. If it is a printed product with a background color, the rubber roller can be adjusted a little lower, with an error of ±0.5mm, so that the ink transferred from the ink roller to the printing rubber roller is more uniform, and the same effect is reflected on the printing plate, making the printed product pleasing to the eye. If not, phenomena such as ink streaks and ink paths will occur.

　　When printing text, the height of the rubber roller should be basically level with or slightly lower than the text plate, so that the printing rubber roller can gently rub against the printing plate, resulting in very clear and clean text printing. The wear surface of the rubber roller is small and not easily damaged, which can extend the service life of the printing plate. During adjustment, a rubber roller adjustment tool should be used. Before use, the printing plate should be removed, and the adjustment roller should be inserted and pulled out a few times to level it. The size of the ink dots on the adjustment roller will immediately be displayed, and the operator can determine the height of the printing rubber roller according to different printing needs, and then secure the top screw. This way, the height of the rubber roller will not change during high-speed printing.

　　If we lack patience when using the rubber roller and are eager to achieve results for convenience, the following situations may occur:

(A) The rubber roller may show surface damage, flaking, causing the text printing to be incomplete, unclear, or even resulting in smudging and jumping ink.

(B) The ink coverage on the text is uneven, and there may even be printed products with only text impressions but no ink color.

(C) If the rubber roller is adjusted too tightly against the ink transfer rubber roller, it may damage the printing rubber roller, causing economic losses and equipment accidents. In the technology of offset printing, the key is the control of the balance between the water path and the ink path, and the balance of water and ink relies on the rubber roller and ink roller, which are key components whose quality directly affects product quality. This is even more true for gravure, relief, and flexo printing.

　　General printing companies must maintain their equipment once a week, which includes the maintenance of the printing rubber roller. The maintenance methods are as follows:

1. After completing daily production operations, the rubber roller should be carefully cleaned and washed twice.

2. Cleaning the printing rubber roller must use designated chemical agents, such as industrial alcohol, and must not use corrosive solvents.

3. During holidays, the rubber roller should be removed to prevent deformation due to pressure.

4. For the protection of the surface of the printing rubber roller, it should be wrapped in newsprint and placed in a ventilated, dark place. In the working process, the printing rubber roller usually shows wear, holes, and other phenomena. If a new roller is replaced, the cost is too high and affects production progress.

　　Rubber repair agents can be used for repair. The repair process, taking rubber repair agents as an example:

1. Surface treatment: The area to be repaired should be roughened, cleaned, degreased, and dried.

2. Mixing the repair glue: Pour the curing agent B group of the rubber repair agent into the main agent A group and stir quickly until evenly mixed (A:B=1:1), then pour it onto the area to be repaired and smooth it out.

3. Curing: It can be used after curing at room temperature for 4-6 hours, and reaches maximum strength after 48 hours.