The effect of paper hand-over transfer on overprinting

The J2205 offset press conveys the paper through the swinging paper and transfers the paper from the paper transport station to the impression cylinder, so that single and double color printing can be performed. The paper handing tooth played the role of transportation and bridge in this process and completed the job of receiving paper, transferring paper, and putting paper. The work was done in a certain position according to certain rules. If due to the paper-feeding tooth itself or other factors, can not follow the specific rules to complete the paper transfer work, it will cause overprinting faults.
In the daily product sampling inspection, we found that in the same batch of products, in the absence of any change in its rules, with the increase in printing speed, the product showed a variety of rules (previous regulations) phenomenon, and imprinted gradually dragged on The direction of the tip moves, but the dimension of the pull gauge does not change. Therefore, we analyzed and overhauled the J2205 machine that caused this phenomenon.
The paper is fed from the paper feeder and transported to the front gauge. The front gauge and the side gauge position the paper. The paper is in perfect condition. We printed at 5000 prints/hour, 5,500 prints/hour, 6000 prints/hour, and 6,500 prints/hour. We compared the dimensions of the product's front gauges and found that there were four kinds of print rules for the four kinds of print speeds. The dimensions are basically the same in the lateral direction. That is to say, as the speed of the J2205 machine increases, the imprint is gradually removed toward the tip. It can be seen that during the process of splicing, transferring, and feeding of the paper-feeding teeth, the paper is compressed when the impression cylinder squeezes its teeth, so that a small amount of displacement occurs in the printing process. The key to this is whether the swinging feed teeth perform the action according to the standard. Therefore, we focused on the inspection of the delivery teeth, especially the observation of the main movement points, and the disassembly of the parts connecting the delivery shaft and the delivery tooth spindle. The result was found to be fixed on the swing feed shaft. The 3 needle roller bearings, due to lack of oil for a long time, the roller needles dry and friction between each other, so that the clearance between the needle rollers is too large, and a few bearings inside a few needles, needle rollers and needles within the bearing The gap increased. In this way, when the printing speed is increased, the distance between the inner and outer rings of the bearing cannot be guaranteed to be the same, and the distance between the two points of the inner ring and the outer ring fluctuates and the distance between the inner ring and the outer ring fluctuates and the distance between the two points of the outer ring fluctuates. Variety of rules.
Through the above analysis, we replaced the bearings of the same type and lubricated in time, and the above phenomenon no longer occurs.