March 19, 2004 -- A trailblazing technical innovation opens up new savings potentials on sheetfed presses: DirectDrive, the direct drive of the plate cylinder, makes possible parallel plate change on all printing units at the same time. During the plate-changing operation, wash-up processes can take place in addition. A glimpse into the future of sheetfed-press drive technology At drupa, MAN Roland will offer the hundred-thousands of visitors a look at the latest development in drive technology for sheetfed presses. The direct-drive principle known from use in commercial and newspaper web-fed presses, now modified for sheetfed machines, will be demonstrated on a printing unit of the ROLAND 700. Longitudinal shaft and DirectDrive – no contradiction in itself To transfer advantages like decoupled or parallel makeready operations and precision drive to sheetfed offset requires approaches different from those in web offset. In sheetfed offset, the combined feed of force from the drive motor via longitudinal shaft and gearing continues to offer many advantages, especially with long perfectors. Besides, many transfer elements of the sheet guiding system are in constant mechanical contact. Malfunctions of different drives, which on webfed presses cause a web break at worst, would immediately result in mechanical destruction on sheetfed presses. On these, therefore, the direct drive is confined to the plate cylinder. It is mechanically decoupled, directly driven by a high-torque motor mounted on the cylinder journal. A 360° circumferential register further makes the ROLAND 700 variable for using different plates from presses of other makes, differing in image start. Exact control with high quality potential In the process of implementing the direct-drive technology on sheetfed presses many synergy effects became available that are derived from the expertise of the world-market leader in web offset. This has led to a convincing result: Integrated in an automatic control circuit with the blanket cylinder, the plate cylinder maintains its position exactly – at least as exactly as with mechanical gear drive and partly even better in tests – with a deviation tolerance of less than ten thousands of a millimetre. Parallel plate change The ability of parallel plate change is a great advantage. On a ROLAND 700 equipped with APL automatic plate-changing system, all plates are changed in the time it normally takes to change just one. Best of all: Wash-up processes can take place at the same time! That reduces the time for plate change or job changeover to just a few minutes – even on long perfectors with eight, ten or twelve colours. Flying plate change With DirectDrive, the „flying plate change“ familiar on web presses becomes possible also in sheetfed offset. Text changes on a six-colour press, for example, can be carried out without long interruptions of printing – because while the black plate for language version “X” may be running in the fifth printing unit, the black plate for the new version “Y” is loaded in the sixth printing unit etc. Future perspectives The decoupling of printing-forme change and production allows contemplating a press with integrated DICO imaging technology, enabling changing printing formes for different versions while the press is running – without plate change. After a phase of intensive testing and its world premiere at drupa 2004, the new DirectDrive technology on the ROLAND 700 will provide for even more efficient production.