What should you pay attention to when adjusting the amount of ink?

During the printing process, sometimes the amount of partial ink used on the layout is small, or it is blank, no ink is needed, and the ink key is completely closed through the console, but the ink key of the actual ink fountain is not completely closed, and continues to pass. ink. In this way, when printing, the ink on the ink roller will accumulate more and more, which is easy to cause malfunctions such as paste, flying ink, etc., not to mention keeping the ink color of the layout uniform. When there is a large area on the surface, the amount of ink is adjusted to the maximum through the console, but the printed ink is not enough, and the field is partially faint. In addition, there may be cases where the ink fountain of the printing press is not in place and the ink is leaked. Poor ink control can cause a lot of waste, which can seriously affect the quality of printing and even lead to production interruption. Therefore, it is necessary to fully grasp the ink quantity control method and use it flexibly in daily production, so that you can do whatever you want with ink color control.

IMAX function and ink volume adjustment

The printing operator adjusts and controls the amount of ink almost every day through the press control program on the ink fountain and console, but another very simple and effective function in the print control program - IMAX, the people who really understand and use it not much.

You may easily think about the setting of the ink curve, but the setting of IMAX and ink curve is significantly different. The ink curve sets the rotation speed of the ink fountain roller at different printing speeds to ensure the supply of ink; IMAX is in advance The degree of opening of the ink key is set, which does not change as the printing speed changes.

What is controlled by the IMAX function is the degree of opening of the ink key. The degree of opening of the ink key is controlled by the button on the console. Is there any contradiction? In fact, the degree of opening of the ink key is controlled by these two places together, and is first controlled by IMAX. IMAX's ink volume control range is 0 to 100%. When it is set to 0, the ink key motor will not run even if the ink key is turned on to 100% on the console; when IMAX is set to 100%, it means The control of the degree of opening of the ink button is completely given to the console.

In the sauna machine, we found through actual test that when IMAX is set to 100% and the ink on the console is also 100% open, the actual opening degree of the ink key is about 0.85mm; when IMAX is set to 50%, the console When the upper ink key is still open to 100%, the measured ink key opening degree is about 0.425 mm. This makes it clear that the relationship between the two ink quantity control methods is clear. For example, for a layout with a large amount of ink for newspapers, we can set IMAX to 45%. When the ink on the console is 40% open, the actual opening degree of the ink key should be about 0.85 × 0.45 × 0.4 = 0.153. Mm. Understand the principle of IMAX function, it is simple to use. When encountering large-format pictures or more in the field, the amount of ink used is larger, we can increase the value of IMAX, so that the ink key is opened larger to meet the demand for ink; on the contrary, when there is very little layout image When the amount of ink used is small, the value of IMAX can be appropriately reduced to ensure more precise and fine adjustment of the ink key through the console. The size of the IMAX value is directly determined by the layout. Normally, it is sufficient to set the IMAX value of the newspaper layout to 40% or 45%, and it is not necessary to modify it frequently. Then, the degree of opening of the ink button and the speed of the ink fountain roller are adjusted through the console. That's it. For some reddish layouts, if there are only a few small words or a few titles on the layout, you can set the IMAX value to 25% or 30%; for a special large-area color version, you can increase it to 60%. In short, it should be used flexibly according to the actual situation.

In addition, IMAX adjusts a single ink fountain, does not affect other printing units of the same press, and does not worry that this adjustment will affect the ink preset, because if we add the IMAX value of a certain ink fountain after the ink preset is completed, From the console, the ink button opening degree of the ink fountain will be automatically reduced by the corresponding percentage, so the IMAX value can be set at any time before starting the machine.

The gap between the ink knife and the ink fountain roller, the ink transfer roller and the ink fountain roller is very important

The gap between the ink knife and the ink fountain roller should ensure that no ink is transmitted when the ink key is completely closed; the most suitable gap between the ink transfer roller and the ink fountain roller is 0.1 mm thick steel sheet when the ink roller is uploaded. It can be pulled out slightly between the two rollers. If the gap between these two places is too small, it is easy to overload the ink drive motor, and the motor will alarm, the ink fountain roller will stop rotating, and the motor will burn out. The most serious situation we encountered was the direct breakage of the shaft connecting the ink fountain rollers on the drive motor.

In order to ensure smooth ink discharge, not only to keep the ink fountain clean, but also to properly stir the ink.

First of all, the ink knife that stirs the ink should not be made of steel, otherwise it will easily damage the ink blade. Secondly, when the ink cartridge is blocked, it cannot be directly used with the ink knife. Finally, the ink is also separated. The temperature in the workshop is low, the ink fluidity is not good, and the frequency of the ink is increased. On the contrary, the ink can be stirred less, and some inks cannot even be stirred. For example, once we print orange-colored spot colors, the amount of ink is relatively large. Each time we stir the ink, the amount of ink will increase, and the thickness change of the ink layer of this ink has a great influence on the coloring effect. When it is enlarged, the layout becomes very red immediately, causing a lot of waste. Therefore, when this situation is encountered, it is impossible to stir the ink, and even the ink application should be carried out as much as possible.