New automatic control technology of the hottest we

2022-07-23
  • Detail

New automatic control technology of web offset press with China's entry into WTO, China has introduced many advanced web printing equipment in the world, making China's printing industry enter a high-speed development stage, and the newspaper industry, commercial printing and packaging printing rise rapidly. The companies represented by Heidelberg, Manroland, gaobao, Komori, Mitsubishi, Xiyan and delant Gerber have all introduced web offset printing machines with new technologies, which have the characteristics of high printing speed, high production efficiency, high automation and good printing quality. The representative new technologies mainly include the following aspects

shaftless transmission technology

shaftless transmission can simplify the transmission device of the printing machine, omit the belt transmission, especially the gear transmission mechanism. The machine operation, operation, installation, commissioning, maintenance, etc. are based on each color deck. It has simple structure and stable operation, and can ensure the printing quality even at high speed. In addition, the operation is very convenient, which can save time, avoid engine oil lubrication, and reduce the machine noise. Because the drive combination (such as drive shaft, clutch shaft, etc.) is removed, the manufacturing cost is greatly reduced

after adopting shaftless transmission, the mechanical vibration of one printing unit may be transmitted to the next printing unit through the transmission shaft, which may cause the accumulation of mechanical vibration, affect the transmission accuracy of the printing machine, and make the printing quality not well guaranteed. At the same time, the independent motor drive is very flexible. It is very easy and convenient to add or remove a printing unit, and the structure of the whole system is simple. Shaftless transmission can also make the machine control highly automated, making the combination between units more simple and flexible, so as to meet the needs of different customers. From the development trend, the market share of shaftless transmission will be larger and larger, and shaftless transmission will replace the traditional mechanical shaft transmission

waterless offset printing technology

in recent years, web waterless offset printing technology has been vigorously promoted, and its market share will further expand. Gaobao, Manroland and and other companies have launched Web waterless offset printing machines. Its characteristics are mainly reflected in the following aspects: first, it completely eliminates the wetting mechanism, makes the ink path control simpler, does not need to consider the ink balance, and the printing production process is easy to be controlled. At the same time, it is conducive to environmental protection without using wetting liquid; Second, the height of the printing press has been greatly reduced. The height of the web offset press is a big problem that puzzles users. Due to the cancellation of the waterway, the height of the printing press can be greatly reduced, and the manufacturing cost and plant height can also be reduced. The height of the same tower structure can be reduced to less than half of the original height; Third, because the wetting liquid has been completely eradicated, the paper will not stretch when encountering water during the printing process. The edge of the printing point is highly clear, especially when printing fine lines or various frequency modulation points. In addition, the ink transfer in the area with large ink volume can reach a high field density without ghost or water roller trace. In addition, the advantages of waterless offset printing also lie in its drying, better printability for non absorbent substrate than waterless offset printing, easy preparation and wide range of impact testing machine for indirect method verification. Seamless technology

the biggest advantage of seamless rubber roller technology is that the rubber roller can achieve complete dynamic balance, which is very important to ensure the stable operation of the machine. This technology requires that the blanket itself is cylindrical, which puts forward new requirements for the manufacturing process of blanket. However, if the manufacturer does not provide this technology or spare consumable materials, this technology will not be widely promoted in the near future

people used to think that the printing quality of web offset press was much different from that of sheet fed offset press. With the application of seamless technology of web offset press, the stability of drum operation was greatly improved, and the printing quality was very close to that of sheet fed offset press. Many live parts printed by former sheet fed offset press can now be completed on the web offset press

the so-called seamless technology refers to the use of seamless rubber cylinder and seamless plate cylinder, that is, the cylinder adopts sleeve structure. The sleeve type blanket and printing plate are very convenient to use. The replacement operation can be completed quickly at the operation side, which can greatly shorten the version replacement time and save the operation of fastening the blanket. After the application of seamless technology, the maximum speed of web offset press is 1.5 times that of ordinary web offset press, and can reach about 1000 meters per minute; The printing width can also be increased by 1.5 times, and the maximum width exceeds 1.7m; At the same time, the production efficiency can be increased by more than 2 times

the use of seamless rubber cloth can improve the printing quality. The mechanical vibration caused by the joint of the blanket of the traditional offset press when it meets with other rollers is likely to lead to the generation of ink bars. This interference will not only reduce the quality of the printed matter, but also limit the improvement of the printing speed and increase the mechanical wear. It can also be achieved at low cost. At the same time, we have to make a compromise between quality and speed. The application of seamless technology eliminates the printing defects caused by mechanical interference. It is the best way to completely avoid the vibration caused by the joint between the printing plate cylinder and the rubber cylinder. In addition, there is no gap between the plate cylinder and the rubber cylinder, so there is no need to add shoulder iron (roller pillow), and the rubber cylinder can be made stronger, which solves the deformation problem of the cylinder. Therefore, the double diameter cylinder is not necessary, and can be made into a single diameter cylinder

seamless blanket can effectively reduce the waste in the printing process. On the premise of equal drum circumference length, the printing area of the web offset press with seamless blanket is obviously larger than that of the traditional press, which can save tens of thousands of yuan of paper cost each year

sleeve technology

delant Gerber company has introduced offset printing technology with variable sleeve size, referred to as VSOP technology for short. This technology enables customers to flexibly replace sleeves of any size on the plate cylinder and rubber cylinder of the offset press without replacing the entire printing unit. Using this variable sleeve size technology, it is convenient and fast to change the printing size. It can complete the replacement of different prints through a few simple steps, even for short edition printing; The price and supply time of sleeve and printing plate are far cheaper and faster than that of flexographic printing and gravure printing. The printing quality is slightly worse than that of traditional offset printing, but it is comparable to or even better than that of flexographic printing and gravure printing; At the same time, the circumference of the plate cylinder and the rubber cylinder can be changed steplessly within a certain range to ensure the normal operation of the machine, so that the printing machine becomes extremely flexible and can almost meet the printing of any different substrate materials (such as film, aluminum foil composite materials, etc.). In the past, sleeve technology has rapidly improved flexographic printing technology and supported the smooth evolution to new LED curing technology in the future. At present, sleeve technology has entered the world of offset printing technology

inkless key technology

ink volume adjustment is a relatively frequent operation. The inkless Key Technology launched by gaobao company on its waterless web offset press completely solves the problem of ink volume adjustment. The core of this technology is to use a corrugated roller to realize inking and inking

needle free technology

Heidelberg company has developed an advanced needle free folding device to match the higher speed of the printing unit, and it is closely connected with the paper saving performance provided by the seamless blanket. The needle free technology also has the characteristics of saving paper. Since there is no need to cut off the paper after punching a needle hole, the non printing part can be minimized, which complements the feature of increasing the printing area provided by the seamless blanket. These new technologies are combined with each other, together with the design of triangle folding device, to provide users with more flexible and diverse products to meet various needs

digital technology

with the application of various new technologies, the web offset press has made great progress, especially the application of digital technology has promoted the offset press to a higher level. DICOweb launched by Manroland company is the representative of Web digital printing machine. It uses heat transfer imaging technology to directly image on the plate cylinder, and the production time of each plate is less than 10 minutes. With this technology, the printing plate can not be replaced and the film can not be used, which can ensure the printing quality, save a lot of auxiliary time and improve the productivity. Web digital printing machine is especially suitable for short version printing. It is simple and convenient to operate. Therefore, it will occupy a certain market in the field of commercial web printing

in addition, by making use of the original technical advantages of offset printing and the pre press and post press integration function formed by combining digital technology, modular design, digital printing software and digital pre press and post press processing system are added to the original offset printing system. By using the network advantages, variable data printing can be realized to meet the on-demand printing of high quality and high productivity

newspaper printing must properly handle the page number, printing number and other issues of the newspaper according to the final production task. With the help of CTP and full page assembly technology, the direct plate making from the digital database to the plate cylinder is finally realized, and the prepress and printing are further connected. Therefore, the digital technology will be further developed on the web offset press

reprinted from: newmaker

Copyright © 2011 JIN SHI