Roller parts adjustment and maintenance

Roller parts adjustment will directly affect the normal use of offset presses and print quality. In addition to strict requirements on the accuracy of the drum parts, there are strict requirements on the adjustment of each part. Only in this way can the drum parts play a good role in the offset printing work and cooperate with other parts. To complete the task of exquisite printing (encyclopedia). The following adjustments must be made to the installation of the roller parts.

1) Ensure that the radial runout of the three cylinders of plate cylinder, blanket cylinder, and impression cylinder is within the allowable range. The roller is positioned by the tolerance of the eccentric sleeve that participates in the cooperation work. Accumulation error is bound to exist between them. The more eccentric sleeves that participate in the cooperation work, the greater the cumulative error will be. It will directly affect the axial and diameter of the roller. Positioning accuracy. Therefore, we should pay special attention to the clearance of the fit when installing the roller bushing.

2) The axial turbulence of each roller shall not exceed 0.03mm, otherwise it will cause print quality failure.

3) Offset printing is a unique printing method that requires wetting of the printing plate surface with fountain solution. Offset fountain solution contains acidic substances, surface active substances, etc. It has certain corrosiveness on the surface of the three cylinders of printing plate, rubber, and embossing. In particular, the printing plate roller is in contact with the fountain solution for a long period of time. If the printing plate cylinder is eroded seriously, it will cause irregularities on the surface of the printing plate, resulting in illegibility of the graphic network dots and partial printing pressure. Repairing a plate cylinder is an extremely troublesome thing.

In order to prevent the dampening solution from eroding the plate cylinder, the best way is to apply a layer of butter to the two sides of the backing plate of the plate cylinder and the blanket cylinder. Using the principle of repelling oil and water, the fountain solution cannot penetrate into the plate cylinder and eraser. Within the drum, to achieve the purpose of maintaining the printing plate cylinder.

4) For the impression cylinder, in addition to ensuring the same requirements as other cylinders, it is also necessary to pay attention to the normal function of a set of dental caries with the impression cylinder. Printing faults such as inaccurate overprinting, tearing, crumpled paper, and ghosting are mostly caused by the abnormal condition of tooth decay. Therefore, while maintaining the impression cylinder, it is necessary to pay attention to whether the work condition of the gripper is normal. Lubricants are often added regularly to keep them lubricated for a long period of time and they work under good lubrication conditions.

5) The printing rollers should be kept clean. For the printing plate and the rubber roller, it is more important to ensure the cleanliness of the shoulder iron and a small part of the exposed roller parts. If the ink is stuck, it should be cleaned in time, otherwise it will be in the cylinder body. Long-term accumulation of ink around the block and form. The agglomerated ink is located in the gap between shoulder rollers of the press roller, which affects the normal printing state of the roller, and will cause impact bounce at the ink layer bump, causing inaccurate ink bars or overprints.

6) If the roller bearings, roller gear sets and other components will not be cleaned for a long time will speed up the wear between them, the machine equipment is unfavorable. Because the impression cylinder is often exposed, the cylinder body is often affected by various external factors, so care should be taken to maintain the impression cylinder body. Each class should be cleaned in a timely manner to clean the surface of the work, and the ink blots attached to it should be cleaned to keep the work surface clean.

7) In the process of use, we also need to install the plate cylinder clamping device, and rubber blanket curling mechanism regularly check, found that the problem in a timely manner to deal with, so that the roller parts are maintained in the best state to run.