8 cylinders and 10 cylinders COLORMAN print quality difference

Germany's Mann Rolland is one of the world's largest printing equipment suppliers. Its COLORMAN model is one of the most advanced printing machines in the newspaper industry. It is divided into 8 cylinders and 10 cylinders, COLORMAN. Both models have different degrees in the country. usage of. Guangzhou Daily Printing Center, as the most powerful printing facility in China, can print up to 6.54 million pairs per hour. The Printing Center has the world's most advanced seven printing production lines, including two each of the 8-roller and the 10-roller COLORMAN models from the German company Roland.

Although the same is the COLORMAN model, the print quality of the 8 and 10 cylinder COLORMAN is very different. For example, the 10 cylinder COLORMAN print title is imaginary, the layout is not even, and the 8 cylinder COLORMAN printing is difficult to register. Therefore, the author will analyze the causes of these differences and discuss the methods to solve them in light of the actual production practice.

First, the reasons for the difference

1. Structural differences

The 8 cylinder COLORMAN model is the most mature technical representative of the company's 20th century mainstream mainstream axis-driven rotary presses, with a maximum print speed of 75,000 copies per hour.

The 10 cylinder COLORMAN model is the top product of Mann Rolland. It represents the most mature technology and the best and most reliable product for newspaper journal printers. The 10 cylinder technology reflects the most advanced design concept of the world press rotary press. At present, the same type of 10 cylinder equipment is mainly concentrated in developed countries in Europe and America. The highest printing speed is 85,000 copies per hour. It has the characteristics of flexible paper path, humanized maintenance interface, high precision of registration, low waste rate, and better printing quality.

A shaft drive uses a single spindle to transmit power, and each part is transmitted by a transmission gear to transmit the moment. Although the design considers the influence of torsional deformation, this deformation is inevitable. In the non-shaft transmission mode, there is no mechanical shaft twisting and backlash between gears. Therefore, the so-called transmission error will not occur, and deformation and wear will occur when the gears are pressed and pressed for a long period of time. This will affect the power transmission accuracy and cause overprinting errors of the printed products. The system will not produce this kind of defect. So 8 cylinder COLORMAN printing is relatively difficult to register.

2. Differences in printing paper path

8 cylinder COLORMAN both sides of the same time printing, and 10 cylinder COLORMAN both sides are not printed at the same time, the first printing of the positive four-color overprint, and then the reverse printing of the four-color overprint. Since the frontal C, M, Y, K four-color overprinting is completed, the reversed four-color imprinting is performed. In this way, the positive graphic and field inks are imprinted again within a very short time after the printing is completed. Roller, then there will be a situation: In the case of ink is not completely dry, to some extent will be adhered to the embossing roller, resulting in the graphic part is not strong, the real hair is missing or even missing, resulting in the layout is not Leveling and other phenomena.

Second, the solution method

1.8 Roller COLORMAN printing register problem

For the 8-roller type shaft drive structure can not be changed, the transmission error is unavoidable, only in actual production, pay special attention to the maintenance and repair of the machine drive system, try to minimize this transmission error.

The printing machine is equipped with an automatic registration system, which uses the electric eye to automatically track the color markings printed in front of the two colors, and then feeds back signals to the control center to control the center to automatically make correct adjustments and achieve print registration.