Press release BoxID: 127569 (Koenig & Bauer AG)
  • Koenig & Bauer AG
  • Friedrich-Koenig-Str. 4
  • 97080 Würzburg
  • Contact person
  • Martin Dänhardt
  • +49 (351) 833-2580

Simultaneous plate changing boosts short-run productivity

DriveTronic SPC open house at KBA in Radebeul

(PresseBox) (Würzburg, ) On 20th and 21st September, KBA welcomed some 500 guests from over a dozen European countries to an open house at its sheetfed offset manufacturing facility in Radebeul to present the DriveTronic SPC direct plate cylinder drive technology for simultaneous plate changing and consequently impressive productivity gains at job changeovers on the high-performance Rapida 105 press.

Over most of the previous two years, the KBA DriveTronic SPC technology had already been tested quietly under real-life conditions at ten European users representing the most varied market segments (commercial, book printers, publishing houses and packaging), gathering important feedback for further optimisation. Almost 150,000 automatic plate change cycles and the high-speed production of over 100 million printed sheets demonstrate admirably the reliability of the gearless direct drive technology for the plate cylinder, which is available with immediate effect as an option for the medium-format Rapida 105 series.

Pioneer of dedicated drives in sheetfed offset

KBA is the industry pioneer in the field of dedicated drive technology, which has been incorporated into its newspaper presses since 1995 and into commercial web offset presses since 1997. The first applications in sheetfed offset followed already in 2000, with shaftless feeders (DriveTronic Feeder) for all medium and large-format Rapida models. Alongside the elimination of all typically wear-prone components, the benefits of the DriveTronic Feeder are to be seen in the exact timing of all feeder motions, the jerk-free pile transport, smooth sheet deceleration on the feed table, and the precise arrival of the sheet at the front lays.

At Drupa 2004, the sidelay-free infeed DriveTronic Side Lay (= SIS: Sensoric Infeed System) was presented as a further unique feature for sheetfed offset printers. In the meantime, more are more KBA presses are being equipped with this system, which continues to return outstanding results in practical use. DriveTronic Side Lay (SIS) performs the lateral alignment of the sheets by way of a directly driven gripper bar on the feed drum. There is thus no makeready whatsoever for the side lay, banishing the risk of setting errors and ensuring an excellent feed register. With DriveTronic SPC, KBA has set yet another milestone, and has cemented its position as the printing press manufacturer with by far the greatest experience in the use of direct drives.

The heart of the DriveTronic SPC concept is the electronically controlled motor which drives each plate cylinder individually, replacing the previous gears. The key feature is the high torque which is already delivered at low running speeds. At the same time, the plate cylinder is freed from all conventional drive elements such as gears and clutches, further reducing the possible sources of disturbance and wear.

Significantly faster job changeovers

Thanks to DriveTronic SPC, the time required just for plate changing is cut by two-thirds from almost three minutes, for example on a six-colour press with conventional drive, to less than one minute. As a stand-alone function without further automation modules, however, simultaneous plate changing achieves only a minimal saving in makeready time, as much of the time saving is devoured by the other necessary processes. The enormous potential for makeready savings with DriveTronic SPC arises through the various press processes which are able to run parallel to the automatic plate changing (e.g. blanket washing).

Jürgen Veil, head of sheetfed offset marketing at KBA, illustrated this productivity gain where frequent job changeovers are the order of the day by way of practice-oriented makeready scenarios and diagrams. A profitability calculation underlined the cost-effectiveness of the DriveTronic SPC direct drive technology for corresponding production profiles. The economic analyses were based on the following assumptions:

- Manning with 1 printer and 1 helper
- 3 shifts
- 7.4 working hours per shift
- Capacity utilisation 300%
- Availability 85%
- Makeready time per job 17 minutes with and 27 minutes without DriveTronic SPC
- Max. 15,000sph in perfecting mode and 18,000sph in straight printing
- Average run length 10,000 copies
- 1 printing pass
- Profit over production costs and overheads = 10%

On the basis of these values, the annual production output amounts to around 36.1 million sheets without and 41.4 million sheets with DriveTronic SPC. While the press with conventional drive technology is thus theoretically able to handle 3,609 jobs per year, the press with simultaneous plate changing clocks up 4,136 jobs. The incorporation of DriveTronic SPC therefore permits an additional 527 jobs, or in other words an increase of almost 15% in annual output.

Jürgen Veil reminded his audience that, despite the levels of automation which are possible today, the operator and the production environment in the individual printshop remain significant factors in the productivity equation. “A Ferrari is also only really fast with a driver like Michael Schumacher in the cockpit,” he commented. “With my weight on board, it would no doubt have a few more problems cornering.”

Payback period of just a few months

The payback period is influenced decisively by the planned revenue. If the owner of the Rapida 105 SPC decides not to pass on the benefits of faster makeready to the customers, then this results in a payback period of nine months for the automation module DriveTronic SPC (based on 250 working days per year). For the press as a whole, the payback period is then 33 months. If the cost benefits are passed on, the payback period is practically the same for presses with and without DriveTronic SPC.

As representatives of the practical users, Patrick Klewitz and Kurt Conrad (rlc-packaging group) reported on their experience from almost two years of production with DriveTronic SPC in the company's pharmaceuticals centre (see also press release no. 07-094-R-Pharmacenter). Michael Bergmann, managing director of AKA Print in Aarhus/Denmark, where the eight-colour Rapida 105 presented at the open house is shortly to be installed, identified the significant boost to productivity, born out by the positive experience of other Scandinavian users, as the determining factor behind the investment decision.

Record-breaking press demonstration

Within the framework of a live demonstration, the eight-colour perfector press printed a brochure with four cover pages and 48 pages of content (three sheets of 16 pages each), i.e. four different jobs of 500 copies each, in just under 24 minutes! Put another way, this time sufficed for three plate changes for the content sheets and a full makeready with substrate, format and plate changes for the cover. Whereas the content was printed on 135 gsm LuxoArt Silk in format 630 x 880mm, the cover required conversion of the press for a 250gsm substrate in format 650 x 920mm.