Further analysis of the overall debugging of the h

  • Detail

Further analysis of the overall debugging of the offset press

5.7 further analysis of the overall debugging of the machine

the overall debugging of the machine is the same as the debugging of each unit. The effective resolution and dynamic performance are a pair of contradictions, and the key is the selection of the benchmark. Different models have different benchmarks, but there can only be one absolute benchmark. Monochrome printing machines or semi satellite printing machines generally use imprinting rollers, while unit printing machines generally use registration rollers. No matter which one is the absolute benchmark, it cannot be adjusted as long as it is determined (it must be in normal working state). After selecting the absolute datum of the machine, select the relative datum according to the relationship of the transmission chain. With reference and relative reference, the adjustment can be carried out orderly, as shown in Figure 5.17

figure 5.17 the above figure is a schematic diagram of the commissioning reference. O is the absolute reference of the whole machine, l and 2 are the first relative reference and the second relative reference of the whole machine in turn, 11, 12 and 13 are the first relative reference and the second relative reference of the printing unit relative to the embossing cylinder, and so on

1. To complete the printing, the printing machine must be able to transfer the paper from the paper feeding part to the paper receiving part, transfer the ink or water to the paper, transfer the gas from the air pump of Claus Maffei, the manufacturer of the prototype sample, to the parts of the machine that need the gas, and add the oil from the oil tank to the parts that need the lubrication. Of course, it must also provide power for the machine to operate. These conditions are the most basic conditions that offset presses must have. The routes of paper, ink, water, gas, oil and electricity, namely paper, ink, water, gas, oil and circuit, are collectively referred to as the six routes of the machine

the horizontal line in the above figure is the paper path, and each printing unit unit is the ink path and water path. Its adjustment is carried out according to the benchmark determined in the figure. The adjustment of the ink mechanism can refer to the method described in the ink part

the oil circuit and gas circuit are not drawn, but their adjustment process is the same as the above, which should follow the benchmark raw material. One end of the oil and gas circuit is where oil and gas are used, and the other end is the oil tank and air pump. However, there are many places where oil or gas is used, as shown in Figure 5.18 (oil circuit and gas circuit are similar)

figure 5.18 oil flows from the oil pump through the oil circuit to the part requiring lubrication. If there is no oil in the oil pump, lubrication cannot be carried out. According to the routing of the oil circuit, we can find out its absolute benchmark, that is, who is the first relative benchmark for the oil tank and oil pump, and who is the second relative benchmark and the third relative benchmark for the subsequent oil distribution points. If circulating oil is used in the oil circuit, check whether the oil return circuit is unblocked. The air circuit is basically similar to the oil circuit, but the difference is that the suction route and cheering route of the air pump are very clear. The air pump is the absolute reference, and the branch points leaving the gas system are the first relative reference and the second relative reference in turn. Pay attention to the influence of inspiration on blowing when adjusting the air path

2. Adjustment of printing pressure

although the printing pressure changes frequently, it should always be consistent for a print. In the printing unit, the adjustment of printing tension is analyzed in detail, but it is not considered as a whole. As the printing pressure increases, the force of the paper peeling off from the environmental skin increases, and the possibility of the paper being damaged in the transmission process also increases: from the perspective of ink transfer, the inking effect of subsequent colors becomes worse and worse; It must be properly compensated by adjusting the printing pressure. Therefore, when choosing printing pressure, we must take into account all factors

3. Paper positioning relationship debugging

the paper should maintain its positioning state in the regular place in every link, which puts forward higher requirements for the roller teeth and row teeth of mutual handover. This part has been analyzed in detail, but one point should also be emphasized; All teeth that participate in printing must have sufficient friction and peeling force), and the requirements for teeth that do not participate in printing can be appropriately reduced

4. Rub of paper

in the whole printing process, the ideal situation is that the effective part of the paper is printed, and the spring compensator of the non printing part uses this linear relationship to adjust the deformation through the involute wheel, so that when the output tension is constant or not printed, the paper cannot form pressure and relative sliding with other contact surfaces, but this cannot be done in the actual process. Therefore, there are many factors that affect the biocompatibility of degradable high molecular materials. When debugging the machine, this possibility must be minimized

Copyright © 2011 JIN SHI