Since being launched on the market at Drupa 2008 KBA's high-tech Rapida 106 has undergone a process of continual improvement with the aim of boosting its performance, flexibility and cost efficiency still further. Additional software packages, design enhancements at the infeed and delivery plus a broad spectrum of cross-platform systems have made the Rapida 106 the world champion in makeready and the most productive press in its class.
Although it is no longer brand new, the DriveTronic SIS (Sensoric Infeed System) is still unique on the market. Totally makeready-free, it knows no setting or sidelay errors, nor does it mark sensitive substrates. Its mode of operation is ingeniously simple: a sensor determines the lateral position of the sheet on the feeder board, and as the sheet approaches the transfer point to the first printing unit the gripper on the transfer drum aligns the sheet with the side position specified at the console. The sidelay pull is ±5mm (0.2in). Sheet transport to the infeed line is supported by vacuum-controlled thrust elements, which ensure that the sheets are guided gently to the front lays. This investment in disruption-free production is well worthwhile.
With DriveTronic SPC (Simultaneous Plate Change), each plate cylinder has a dedicated drive, with no clutches or auxiliary drives. The absence of a mechanical connection between the plate cylinder and the Rapida's gear train means that almost all makeready processes can run simultaneously. This saves time. Because sequences run simultaneously, the time required for plate changes no longer features in the calculation: to all intents and purposes it is zero seconds, irrespective of the number of printing units. In tandem with the CleanTronic Synchro high-speed washing system DriveTronic SPC enables the benefits of dedicated drive technology to be exploited to the full.
CleanTronic Synchro is a two-bar washing system. The bar for the blanket is located above the impression cylinder and is easily accessible. The second bar is below the impression cylinder and can be removed from the press quickly and easily via rails. The washing programs for each printing unit can be preselected individually. With CleanTronic Synchro, the washing and plate-changing processes can run simultaneously. The diagram below illustrates a typical makeready process and reveals the potential savings that can be made in conjunction with DriveTronic SPC dedicated drives. The two-minute time gain for each job change translates into a saving of 33 hours after 1,000 job changes.
KBA DriveTronic Plate-Ident is an automation component with multiple functions.
1. Function: Register-Pin Plate Recognition: Very often, if the plate does not sit on the register pins properly due to punching errors or flaws in the rubber coating, it can disrupt the plate-changing sequence. The Rapida 106 is the only litho press on the market with optical register-pin plate recognition. Two cameras at each plate shaft recognise the position of the plate relative to the register pin via register marks. This system will stop the plate-changing sequence if the tolerance limit is exceeded, but allows more play than existing systems. 2. Function: Pre-Registration: DriveTronic Plate-Ident is an optical system that measures plate position via the register marks, so the values measured can be used for pre-registration. The register shift is completed even before the first proof is pulled, and for many jobs no further adjustments are necessary, saving time and waste.
3. Function: Plausibility Check: A mix-up in plate allocation easily happens, and with the Rapida 106 running at such high speeds, it cannot be totally eliminated. DriveTronic Plate-Ident checks the stored job data against the data in the console by scanning a data matrix code exposed with the plate. The system instantly recognises whether the plate is in the correct position within the printing unit, and whether it is in the right language. This, too, helps to avoid needless delays and waste.
The very concept of automation is that it should be all-encompassing. And in makeready, a system is only as fast as the slowest sequence. On many litho presses the coater is the bottleneck. Very often four or five minutes must be allowed for changes of coating formes, and this all adds to the total makeready time. KBA has therefore progressively automated and optimised the changing sequence for coating formes, and our system now represents the benchmark in sheetfed offset. Semi-automatic changes of coating formes on the Rapida 106 currently take just under two minutes. This represents a time saving of 33.3 per cent compared to other presses.
KBA's AirTronic delivery is a new development supporting high-speed production on diverse substrates. New, aerodynamic gripper bars optimise the air flow, preventing air turbulence and reducing the amount of powder required. The distribution and shape of the nozzles on the sheet-guidance system were optimised in accordance with the latest data on flow measurement, and ensure that the sheets float at a uniform height. The dynamic sheet brake slows even the most lightweight of sheets efficiently to create a perfect pile at the delivery. Automatic suction-ring positioning eliminates the need for manual intervention. A new venturi system generates a uniform flow of air that gently deposits the sheets on the delivery pile. By dramatically reducing the volume of air required KBA has also reduced the volume of air trapped in the pile. Basically, all digitally controlled functions can be preset and stored. The operator can preset the air feed for the AirTronic delivery in a minimum of time by accessing a substrate database.
In order to exploit the full potential of the Rapida 106 KBA recommends its QualiTronic color-control system, which measures solid densities on each sheet at maximum production speed—and on both sides of the sheet (before and after the sheet-turning unit) in perfector presses. The values measured on ten consecutive sheets are taken as a reference for automatic ink-key control. With QualiTronic color control, time-consuming manual comparisons take a back seat, and start-up waste drops accordingly.
The press operator at the ErgoTronic console has every function in his field of vision. The individual user-oriented menus support easy, intuitive navigation. The automatic job-changing program handles and co-ordinates the entire makeready process—at the touch of a button. The remote maintenance capability gives the operator the feeling that his press is receiving the best of care directly in KBA's Radebeul factory.
The Rapida 106 is available in a wide range of configurations up to a maximum of 16 printing, coating and drying units, and with a choice of automation levels.