Due to the superiority of its structure, sheet-fed offset presses are increasingly becoming the main products of printing machinery, and the requirements for printing quality are also rising. The domestic offset press manufacturers also developed from the original monochromator and two-color printers to the four-color and multicolor machines. Each color group of a sheet-fed offset press is mainly composed of a plate cylinder, a blanket cylinder, a pressure cylinder, a transfer cylinder, and other ink and accessory systems. The running accuracy of the main drum directly affects the quality of the print, and it has a direct relationship to whether or not it will produce overprinting, reticulation, and uneven coloration. Domestic and foreign well-known printer manufacturers are increasingly demanding the running accuracy of the main drum. The bearing supporting the main drum plays a vital role. In order to improve the quality of the printer and add more value-added, many printer manufacturers have to increase the bearing requirements at all costs. With the development of the history of sheet-fed offset presses, the main roller bearings have also undergone many changes. From the previous brass sliding bearings to roller bearings, from needle roller bearings to roller bearings, from single bearings to combined bearings, from two-ring bearings to three-ring eccentric bearings. The precision of roller bearings is getting higher and higher, installation is more and more convenient, and maintenance is getting simpler and easier. one. Needle bearing The rigidity of the needle roller bearing is much better than that of the tapered roller bearing because of its small roller diameter, and the double row misaligned needle roller bearing developed by the bearing company can make the rigidity comparable to the copper sleeve sliding bearing. Compared with ordinary needle roller bearings, the needle roller bearings used for the printing machine roller bearings have higher needle roller grouping than ordinary ones. The needle roller grouping of the conventional needle roller bearing is in units of 2 μm, while the needle roller grouping used in the printer is in units of 1 μm. In this way, by selecting an appropriate needle roller grouping, the working clearance of the bearing can be made less than 1 μm, and this running accuracy is exactly what the high-quality printer needs. In addition, the grouping of the needle rollers used by the printer can be more than the grouping of the ordinary needle roller bearings, so that the requirement for the wallboard can be reduced naturally. two. Roller bearing The use of needle roller bearings still makes printer manufacturers annoyed with the need for high-precision jackets, and requires experienced installers to find the right needle roller group. In order to solve this problem, bearing manufacturers have developed a roller bearing support scheme for the integrated flange of the outer ring. Roller bearings can be pre-tightened to achieve very good precision and rigidity. And can also use the tapered inner ring to adjust the working clearance of the bearing arbitrarily. This kind of solution can completely realize the requirement of the zero clearance of the printing machine roller bearing. The flanged outer ring solves the installation and lubrication problems for printer manufacturers. This type of bearing is widely used in models of Manroland, Heidelberg, Riuubi Japan, and domestic Northers. Its roller bearing support scheme has become the mainstream solution for roller support in printers. three. Integrated unit Just like the automotive industry and other industries, printer manufacturers also need precision products like bearing suppliers to provide simpler modular components to reduce factory assembly errors and time, reduce rework rates, thereby increasing efficiency and reducing costs. In order to meet this demand, the bearing manufacturer provides a roller support unit with a higher accuracy and a simpler installation and maintenance. Such as the three-ring eccentric bearing unit developed by the bearing company. This bearing unit integrates the bearing and the eccentric sleeve, which not only has the function of the support roller, but also can realize the roller clutch pressure and registration function. Its superiority has been widely accepted by printer manufacturers. The KBA, MAN Roland models and new models in Heidelberg have used this bearing unit on plate cylinders or blanket cylinders. In the retrofit work of the old model, this three-ring bearing support has become the first choice. At present, there is no better solution than the bearing unit in terms of performance, installation and maintenance. The use of its labyrinth seals and cylindrical rollers allows it to be lubricated, grease lubricated and maintenance free for life. Excellent lubrication also makes this bearing the longest in various programs. It makes printer manufacturers move their precision requirements from their own processing and installation production lines to bearing production lines that produce precision products such as bearings. This is also in line with the intensification of modern industry. The above is the various solutions for printing machine main drum support. Due to the requirements of its own precision, the printer has high requirements for the support of rotating and linear moving parts. The above solution can completely solve the need for domestic printer manufacturers to develop their own more distinctive products.
Support roller bearing solutions for the main cylinder of a sheetfed offset press