http://www.lprinting.net/content/?775.html
In the printing process, due to the relative movement between the paper and machine, frequently, the phenomenon of printing quality surface smearing, embodied in print surface coating or printing design is destroyed, lower the quality of printed matter, serious when still can cause discarded reprint, resulting in serious economic loss.Below, long printing group in Heidelberg printing machine, for example, a detailed analysis of print smearing the causes of problems and solutions.
Printing part of the smearing problem:
1. The gauge pass paper tooth cause smearing if before the gauge paper tooth row of teeth surface exist burrs or other hard materials, is easy to make print ceng dirty.Heidelberg printing machine lost beneath the board design has special blowing device, to reduce the paper with the gauge paper tooth row of contact, thus reducing the ceng dirty.
Solution: wash before printing paper tooth surface, check whether the blowing mouth is unobstructed, and through the paste paper tooth piece of cellophane tape bring to solve corresponding position of the smearing problem.
2. Paper tablet to smearing the machine after long time printing job, below the paper tablet easy accumulation hard ink particles, leading to positive smearing paper.
Solution: shall promptly replace worn paper tablet, weekly maintenance carefully clean up the tablet when in contact with the paper.
3. The paper guide rod in smearing pass paper drum at the bottom of the guide rod is good thing, also easy to cause the smearing problem.
Solution: paper guide rod in the paper below the bedplate, difficult to clean up, so you need to use special tools to clean up.At the same time, scrubbing the guide rod surface, smooth to keep contact with the paper.
4. The paper guide to smearing on CD Heidelberg printing machine series, paper printing surface and paper guide contact, easy to produce smearing on the back.In addition, because of printing dust for a long time or paper guide surface hard objects, coupled with the corresponding position is difficult to clean, also easy to produce smearing.If the inside of the paper guide fan, and there is no change in time, will cause the flow dynamics is insufficient;Or printed tissue paper fan is not open, blowing mouth paper for hair, such as dust accumulation and reduce air volume, these will print smearing phenomenon.
Solution: in the absence of special requirements, the paper guide blowing should be in an open position;Pay attention to cleaning the surface of the paper guide in machine maintenance, the machine needs to be out during overhaul, clean up hard paper of the hair and other foreign bodies;If the fan is damaged, should be replaced in a timely manner.
5. The smearing device cause smearing
In Heidelberg SM series printer, haploid diameter roller surface contact with the positive phase transfer.At present, the paper roller equipped with anti-lock smearing devices usually have ceng dirty steel sheet, ceng dirty paper, prevention of tap smearing blue cloth.
When printing, because the paper size have change, easy to make the ink smearing device edge part accumulation, can change the surface characteristics when cleaning and caused the paper to smearing, on the other hand, hard objects may also be a crush surface smearing coating, smearing on the corresponding printing parts.
The solution: on the one hand, to pay attention to the quality of printing paper when printing, prevent hard objects or broken paper will steel sheet crush;When cleaning, on the other hand to pay attention to the protection of surface protective coating.
The paper part of the smearing problem
1. The paper suction wind turbines smearing
Paper suction wind turbines generate smearing is most common, especially in print ink when working.
Solution: adjust the suction rotor suction air volume or adjust the speed of the rotor;According to the pattern position, adjust the suction wind turbines to the position of paper margin;Cleaning hard ink on the surface of the rotor.
2. The flat paper rubbed against dirty
Normal use, flat paper rewinding paper, can be the paper level effectively, is advantageous for the paper, but if we don't often wash, will cause the surface hard ink, this could lead to ceng dirty.
Solution: weekly maintenance when clean up dirt on the surface of the paper.
3. The compressed air fan to ceng dirty
If paper pressure wind fan improper adjustment, there will be a part of the wind to fall the piece of paper, drag to print after smearing.If the paper early fall, thick paper also easy to cause the smearing.
Solution: prior to formal printing a few pieces of printed sample, detailed check on the back of it is presence of smearing phenomenon, adjust pressure wind fan and the location of the cardboard.
No comments:
Post a Comment