“Outside the Box Thinking When Folding“
At Kessler Druck+ Medien (print + media), based in Bobingen /
Germany, folding used to be a neglected part in the production
process for a long time. However, Kessler took the opportunity of
upcoming investments to look at their workflow from a new
perspective: they started in the finishing section and ended up in
the prepress department. Now, Kessler is using a new Stahlfolder TD
112 with a pneumatic twin-lay system and developed individually
tailored imposition schemes in their prepress department.
"Put the rule to the test ", says Arnfried Sittner, managing
director of Kessler Druck+Medien in Bobingen, a town near Augsburg
in Southern Germany. He believes that you have to literally grasp
something in order to fully understand it. And Mr. Sittner makes
you fold: an A5 sheet four-times conventional crossfold - another
sheet: first zickzack parallel to the oblong sheet side and then
another zickzack reducing the long sheet side and finally another
fold by half.
The result: not only is the second version a more gentle and precise way of folding, it also delivers 4 additional pages on the sheet - instead of 32 pages there are now suddenly 36 pages on the sheet. In daily 3b-format-production, this means fewer sheets and fewer signatures for the same job volume. And on top of that the sheets get folded in the same paper grain direction as they were printed.
The prerequisites are new imposition schemes together with the possibility of oblong feeding into the folding machine - which ends-up in an overall higher productivity. Or in other words: completely rethinking of traditional folding processes!
New approach. For a long time, folding at Kessler has been treated as an orphan - like with many other traditional sheetfed offset printers as well, says Mr. Sittner. The technology was antiqued, processes not as efficient as they could have been. "We went down to the fundamental principles", explains Mr. Arnfried Sittner. "fundamental" means for Kessler on one hand, to have a close look at throughput times, performance, portfolio and volume. On the other hand it meant not only to look at folding or finishing as isolated steps but to create a holistic approach for the entire company: "We do not only process data, print or finish - we are producing integrated printed products", says Mr. Sittner. "Therefore we also think in terms of a final printed product, not of individual production steps anymore".
The focus for Mr. Arnfried Sittner is the processed material - namely paper. His credo: "Paper is a living raw material and the less it is being stressed and manually handled, the smoother it's going to be processed." Starting from the paper mill delivery and continuing all the way through the entire production chain. As a consequence, Kessler for example uses long perfecting presses, all of them equipped with Preset-Plus feeders and deliveries from Heidelberg, to cut down manual interferences to a minimum. Therefore the smooth handling of the paper also was an important aspect when it came to a new investment into a folding machine. "If your press already provides you with perfectly palletized sheets, you definitely want a folder which feeds the sheets without touching them again. Otherwise all your efforts for accurate paper handling prior to folding were wasted", Mr. Stittner is sure. "Gentle paper handling means faster production speeds, better quality, less sources of errors and faster response times."
The result: not only is the second version a more gentle and precise way of folding, it also delivers 4 additional pages on the sheet - instead of 32 pages there are now suddenly 36 pages on the sheet. In daily 3b-format-production, this means fewer sheets and fewer signatures for the same job volume. And on top of that the sheets get folded in the same paper grain direction as they were printed.
The prerequisites are new imposition schemes together with the possibility of oblong feeding into the folding machine - which ends-up in an overall higher productivity. Or in other words: completely rethinking of traditional folding processes!
New approach. For a long time, folding at Kessler has been treated as an orphan - like with many other traditional sheetfed offset printers as well, says Mr. Sittner. The technology was antiqued, processes not as efficient as they could have been. "We went down to the fundamental principles", explains Mr. Arnfried Sittner. "fundamental" means for Kessler on one hand, to have a close look at throughput times, performance, portfolio and volume. On the other hand it meant not only to look at folding or finishing as isolated steps but to create a holistic approach for the entire company: "We do not only process data, print or finish - we are producing integrated printed products", says Mr. Sittner. "Therefore we also think in terms of a final printed product, not of individual production steps anymore".
The focus for Mr. Arnfried Sittner is the processed material - namely paper. His credo: "Paper is a living raw material and the less it is being stressed and manually handled, the smoother it's going to be processed." Starting from the paper mill delivery and continuing all the way through the entire production chain. As a consequence, Kessler for example uses long perfecting presses, all of them equipped with Preset-Plus feeders and deliveries from Heidelberg, to cut down manual interferences to a minimum. Therefore the smooth handling of the paper also was an important aspect when it came to a new investment into a folding machine. "If your press already provides you with perfectly palletized sheets, you definitely want a folder which feeds the sheets without touching them again. Otherwise all your efforts for accurate paper handling prior to folding were wasted", Mr. Stittner is sure. "Gentle paper handling means faster production speeds, better quality, less sources of errors and faster response times."
Stahlfolder TD 112 with pneumatic twin-lay system. In his
attempt to create a holistic solution, Mr. Sittner counted on the
development support of Heidelberger Druckmaschinen AG - in prepress
and press as well as in the finishing section. "Heidelberg
appreciated the attempt to handle paper in a different way", says
Mr. Sittner. "This was a very impressive experience for us."
And finally, the ideas materialized in technical solutions: with the new pneumatic twin-lay system now available for the Stahlfolder TH- and TD-folder series - launched by Heidelberg on Ipex 2010 and in daily production at Kessler Druck+Medien with a Stahlfolder TD 112. This technology facilitates oblong sheet-feeding and at the same time increasing the productivity by approximately 30 percent. By feeding sheets oblong and folding in the first parallel folding unit, the reduced infeed length of the sheet directly translates into higher productivity at the same physical machine speed. However, on the second folding station, which is arranged at a 90 degree angle, again the full infeed sheet length needs to be transported. In the past, this resulted in a much higher speed of the second folding station, creating folding problems and a deterioration of quality.
With the pneumatic twin-lay system the folded sheets are being aligned and transported prior to the second folding station on two parallel side lays. This way twice as many sheets can be transported and thus the speed of the second station can again be reduced to the half. Quality is being increased, the material is handled more gently and the folding process becomes more stable. In addition, as mentioned in the above folding example, oblong feeding in combination with the new imposition schemes also makes the most of the printed sheet and can place additional pages on the sheet. At Kessler this meant creating new imposition schemes, testing and designing an imposition scheme catalog for technical and sales staff to promote and counsel their customers. "We have re-designed a good share of our own product portfolio, other parts have been modified or extended.", says Mr. Sittner. The key to success was to look at the final products from the end of the production process and to include all participated people in the process. A special focus lies in the cooperation between prepress, which is taking care of the imposition schemes, and the finishing section. "We have the advantage of being a full service provider", says Mr. Sittner.
Certainly, both Arnfried Sittner and Volker Walz of Heidelberg Postpress agree, the Stahlfolder TD 112 with pneumatic twin-lay system is not suitable for every print shop and each job structure. "The machine is designed for long runs. If fast make-ready is crucial, then our Stahlfolder KH 82 is used.", says Mr. Sittner. "The TD 112 is a machine designed for an industrial print production process and needs to fit in the individual company concept."
Martina Reinhardt (Deutscher Drucker Nr. 12, 2011 / Germany)
And finally, the ideas materialized in technical solutions: with the new pneumatic twin-lay system now available for the Stahlfolder TH- and TD-folder series - launched by Heidelberg on Ipex 2010 and in daily production at Kessler Druck+Medien with a Stahlfolder TD 112. This technology facilitates oblong sheet-feeding and at the same time increasing the productivity by approximately 30 percent. By feeding sheets oblong and folding in the first parallel folding unit, the reduced infeed length of the sheet directly translates into higher productivity at the same physical machine speed. However, on the second folding station, which is arranged at a 90 degree angle, again the full infeed sheet length needs to be transported. In the past, this resulted in a much higher speed of the second folding station, creating folding problems and a deterioration of quality.
With the pneumatic twin-lay system the folded sheets are being aligned and transported prior to the second folding station on two parallel side lays. This way twice as many sheets can be transported and thus the speed of the second station can again be reduced to the half. Quality is being increased, the material is handled more gently and the folding process becomes more stable. In addition, as mentioned in the above folding example, oblong feeding in combination with the new imposition schemes also makes the most of the printed sheet and can place additional pages on the sheet. At Kessler this meant creating new imposition schemes, testing and designing an imposition scheme catalog for technical and sales staff to promote and counsel their customers. "We have re-designed a good share of our own product portfolio, other parts have been modified or extended.", says Mr. Sittner. The key to success was to look at the final products from the end of the production process and to include all participated people in the process. A special focus lies in the cooperation between prepress, which is taking care of the imposition schemes, and the finishing section. "We have the advantage of being a full service provider", says Mr. Sittner.
Certainly, both Arnfried Sittner and Volker Walz of Heidelberg Postpress agree, the Stahlfolder TD 112 with pneumatic twin-lay system is not suitable for every print shop and each job structure. "The machine is designed for long runs. If fast make-ready is crucial, then our Stahlfolder KH 82 is used.", says Mr. Sittner. "The TD 112 is a machine designed for an industrial print production process and needs to fit in the individual company concept."
Martina Reinhardt (Deutscher Drucker Nr. 12, 2011 / Germany)
Outside the box thinking when folding
"Put the rule to the test "
