Gaussian and automatic conversion technology

The preference of advertisers and consumers for personalization has contributed to the market's demand for personalized print. From the traditional printing of the object of delivery by region or population to the printing of on-demand and completely personalized one-on-one printing, the market demands for personalization, cost, and timeliness continue to increase.

In order to cope with the ever-changing market, the rotary offset printing workflow is rapidly escaping from printing only long-lived prints, using innovative technologies to integrate the speed and cost advantages of web offset printing, reducing scrap rates, changing time, and over-length. These innovative capabilities help web offset printing companies to be more professional in the fierce market competition, have stronger competitiveness, and get more value.

Non-stop printing

Goss International's Automatic Transfer (AT) technology is a good example. With this technology, the web offset process completes the transition from downtime to continuous printing.

The Gaussian Sunday rotary press using AT technology utilizes the press-to-disc interaction of the printing unit to complete the "seamless" transition between jobs. At the same time as the printing press is running, the operator can prepare the idle printing unit (pressure-relieving) in advance, and then press the control button to stop the running printing unit from being pressed off, so that the ready-to-use printing unit is ready to be used. Pressurized operation, this process does not need to stop, does not even need to reduce the printing speed. Figure 1 shows the "seamless" transition at high speed printing.

In 2005, this technology received the InterTech Technology Award from the Printing Industry Association/Printing Technology Council (PZA/GATF). Five presses and six presses of rotary presses (using two AT units) can perform a single color job change during the printing process. The 8-color printing (8 AT units) using AT technology that has recently been installed in North America enables the replacement of four-color jobs.

A simple example illustrates the working principle of AT technology. An international catalog manual (manual text consisting of multiple languages) was produced using a rotary press with six printing units. The first four printing units print the CMYK color, and the fifth printing unit prints the first language text. When the first 5 printing units are in operation, the 6th printing unit is in an idle state (pressure-relieving), and a printing plate of a second language is mounted on the printing unit. After the printing process of the current 5 printing units is completed, the 6th printing unit with the printing plate is added to the printing process by AT technology (from the pressure-off state to the pressure state), at this time, the 5th printing unit is immediately Leaving pressure, being idle, and starting to install plates in the third language. From the above steps, it can be seen that four-color printing is continuous printing, and the replacement of the language-text printing plate can be completed on the idle (off-pressing) printing unit, so that the printing press can be operated without downtime and without shutdown. .

In order to complete the conversion of the 4-color job, the Sunday press with AT technology can have 8 printing units (CMYK+CMYK). Through the conversion between two sets of CMYK4 color printing units, 4-color jobs can also be quickly converted.

Versatility and print quality

The AT technology uses a linear drum arrangement that does not affect the print quality and position of the printing unit on the press because it does not use an exhaust roller or commutator. Because of this, each AT unit can be installed anywhere on the press. Compared with traditional printing presses, AT units can also be printed on both sides. Eight printing units using AT technology can also perform 8-color printing.

Special structural design

The versatility of Gaussian AT technology stems from the special design of the initial mechanical structure of the Sunday press. The stamping structure of the Sunday press uses a unique patented technology for rotating the drum frame around the shaft. Compared with the traditional rotary press, this structure makes the separation of the blanket cylinder more accurate. In addition, each roller uses shaftless rotation, so the printing speed can be changed simultaneously. In the case of fast operation, tension changes or web breaks are avoided when the idle printing unit is pressurized. While a printing unit is idle, it is possible to carry out plate change operations, simple setup and maintenance. These processes, including change versions, are fully automated operations.

Automatic version change

Automatic plate change system is complementary to automatic conversion technology. This system allows faster and more accurate operation when changing the idle printing unit. The system is suitable for all plates up to 79 inches (2 meters). While one printing unit is idle, the plate of the next job is installed into the printing unit's printing box, and then the old printing plate on the printing plate is automatically replaced with a new printing plate. All plates can be automatically replaced by the operation console's touch screen, and the automatic change between jobs can be completed within 60 seconds. Automatic plate change technology greatly shortens the replacement time of printing plates, and also reduces the error caused by man-made plate replacement. The accuracy of the automatic plate change is very high. At the same time as the automatic plate change, the operator can also prepare for other operations.

Return on investment

Automatic conversion technology can realize continuous printing through the conversion of various printing plates, which greatly improves the production efficiency and reduces the reject rate. Figure 2 shows the comparison of the two modes.

Calculated according to the average running length of the job, rotary presses with automatic conversion performance can increase job productivity by 20% to 200%. Due to the need to invest in additional printing units, the investment cost of AT technology is higher, but the production efficiency of the printing press is high, more printing jobs will be completed, and the investment cost can be quickly recovered.

In the job replacement process, using AT technology can greatly shorten the preparation time and reduce waste (40% waste compared to traditional printing).

When evaluating the characteristics of automatic conversion technology, there are two additional factors that are important: The first is the potential for the technology to reduce labor costs and the impact of human operations; the second is that AT technology brings about web offset printing. The advantages of reducing preparation time and reducing waste, these advantages can make web offset printing begin to enter the business field of sheet-fed offset printing, and bring new applications and new market opportunities for the web offset printing market. For example, commercial web offset suppliers had previously been uncompetitive with short-run printing and variable factors, but AT technology enabled commercial web offset suppliers to start developing new markets in these business areas and serving those markets. client.

The characteristics and advantages of automatic conversion technology Continuous printing, no need to shut down to replace the printing job 2. Reduce preparation time and waste For the short-run printing and variable factor printing business more price advantage 4. Versatility - You can choose the AT unit to print additional colors 5. Does not affect printing quality and production capacity