6. Axle caused by abrasion of the bridge gear. The two bridge gears of the chain roller are equipped with eccentric devices. After the adjustment is appropriate, certain screws must be tightened to leave a certain clearance. If there is excessive noise, if the lubrication is not in place, and there are dirt and oil between the teeth, it will cause serious gear wear, resulting in intermeshing of the gears, vibration of the ink string rollers, and noticeable ink bars on the printing plate.
7. Rubber roller aging hardened caused by ink bars. For printing plants mainly based on books, 01 offset press operators do not frequently wash the rubber rollers, the ink is accumulated on the rollers for a long time, and the dust in the paper permeates the surface of the roller. After the friction, the surface is chipped and cracked. , Luminescence becomes harder, the roller's even ink performance is reduced, resulting in a pronounced ink bar. If the aging of the rubber roller is not serious, but only a layer of glossy film is formed on the surface, the rubber roller can be removed and the surface can be lightly rubbed with pumice powder to completely remove the surface ink and the ink bar will disappear or be relieved. For example, if the rubber roller is severely aged without elasticity, the rollers will slip during operation and the roller must be replaced.
8. Vibration produced by the ink bar. 01 The offset roller of the offset press is relatively large. During operation, the pressure between any two rollers continuously disappears at the neutral position and appears at the entrance. The impact of the roller into and out of the formation of vibration sources, in particular the vibration generated by the impact of the dump, so the existence of the vibration source of the offset press is the main reason for the vibration bar. In the normal operation of the machine, these vibration sources instantaneously disrupt the uniform rotation between the rollers. Once the vibration lever is found, the vibration source should be found first, and the symptom of the lower ring will be complicated and simple.
9. Ink bars produced by printing pressure between plate cylinder and blanket cylinder, blanket cylinder and impression cylinder. Most of the theoretical requirements for the width of the impression between the plate cylinder and the eraser is 4 ~ 6mm, the width of the impression between the blanket cylinder and the impression cylinder is 5 ~ 7mm, but the operator to adjust the center distance is accurate, the ring The quantity was not accurate, but the imprinting was found to be inaccurate. At the same time, she added padding paper. Sometimes she felt the tightness of the blanket. When the pressure was high, she would catch up and there would be an ink bar like a washboard on the blanket.
10. Other causes of ink bars. If the ink is too thin, the stickiness is easy to produce, the coated paper is easy to get out of the ink bar when it is printed on the ground or on the cable, the dark ink is easy to get out of the ink bar; the thickness of the pad is uneven, and the quality of the blanket is easy to get out of the ink bar. .
11. The water bar is also called the white bar. The generation of the water bar on the low speed machine is generally caused by the large contact pressure of the water roller on the printing plate. The feature is that the printing plate is shiny and has a fixed bar. 01 The offset press water supply mechanism is controlled by a cam, and the water is conveyed at the position of the plate cylinder. The position of the transfer roller control cam and the contact time of the printing plate should be correctly adjusted and the appropriate pressure should be used. General 01 machine has two water rollers, as long as the adjustment is good, only one can rely on version of the water roller. According to my observation, the following one is generally used. However, when changing the water roller, the operator points the machine to the neutral position and uses a crowbar to pull out the water roller so that the water roller bracket is easily loosened or the water roller is deformed. Therefore, it is still used. A suitable one can prevent the generation of water bars.
12. In production, we also found that when the pressure between the ink roller and the ink roller is light, a water bar will be generated. This is because the pressure between the ink rollers is too light and the ink cannot be uniformly transferred on the roller and float on the roller. When the ink is not balanced, ink is emulsified due to the thickening of the ink layer on the surface of the rubber roller, and the water bar tends to appear on the printed sheet.
13. The water roller swings the water lever caused by too much vibration. 01 The machine roller swing is controlled by the cam. The machine wears the cam for a long time. There is a jump in the neutral position, the water bar is more obvious, the majority of the water bars are printed around 5,000 sheets, and the printing plate resistance to printing force is reduced.
14. The quality of the water roller sleeve is poor, the local unevenness is uneven, the water-bearing roller is not tightly packed, the two loose ends are tight, and the water supply is uneven or the water volume is too large. Both of them are easy to appear at the first two lines.
In short, when the machine you operate is exposed to ink bars, it must be analyzed in many aspects and clarified step by step. As long as it is handled properly, it can be satisfactorily resolved.