Heidelberger Druckmaschinen AG (Heidelberg) will be presenting its new PFX pallet feeder for the Stahlfolder TH/KH folding machines at drupa 2012 in Düsseldorf. PFX stands for Pallet Feeder eXtended. This new feeder can boost a folding machine's output by up to 50 percent compared with conventional cross-fold production. Despite this much higher output, the entire unit still operates at the same machine speed, thereby ensuring precise folding quality and stable production conditions. 

The new PFX feeder works along the same lines as a press feeder. It separates sheets on the pallet and transports them onto the feed table in a shingled stream. This means that more sheets can be fed into the folding machine in a given amount of time with the machine operating at the same speed. The separation process on the feeder is far slower and far more stable than with conventional folding machines, where each sheet has to be transported separately onto the feed table. Shingled sheets are reliably aligned thanks to the unique Venturi principle of the PFX feeder's vacuum feed table - the prerequisite for processing more sheets in the same amount of time. Such stable operation would not be possible with conventional feed tables. 

"Output and production stability are key factors in long-run industrial print production," explains Stephan Plenz, member of the Management Board responsible for Heidelberg Equipment. "We have now succeeded in extending the principle of the tried-and-tested stream feeder used in our presses to postpress applications so as to deliver lean production with a variety of potential savings," he adds. 

The new PFX feeder will be on show on a Stahlfolder TH 82 machine at the Heidelberg stand in Hall 1 as a response to the HEI Productivity market trend. It will be available to buy from the beginning of 2013.

High throughput thanks to feeding and folding in a shingled stream 
The innovative sheet feeding of the Stahlfolder TH 82 with PFX feeder goes one step further than a press, though. Depending on the job, sheets can remain shingled on the feed guide even after alignment and be transported into the first folding unit still overlapping. The first fold shortens the top sheet sufficiently for the shingled stream to break up while still in the folding unit, with the result that sheets move on separately - and with a space between them - after this initial fold. Shingled feeding and folding represents a big step forward and can boost productivity by as much as 50 percent. 

Integrated production improves productivity by up to twelve percent across the entire process 
In addition to the technical features of the PFX feeder, a key factor in its enhanced performance lies in selecting the correct fold type. This couldn't be easier for customers using the Prinect prepress workflow from Heidelberg, because fold types are specified at the prepress stage. 

In many cases, it is possible to use even more of the print sheet by changing the fold type, for example fitting 18 rather than the previous 16 A4 pages onto one signature. Depending on the end product, this can dispense with one or more print passes. What's more, fewer feeders need to be loaded up at the saddlestitcher or adhesive binder. The total potential savings this achieves across all productions steps can quickly add up to more than twelve percent for each job. 

Folding machines can now match the capacity of high-performance presses 
Long perfectors from Heidelberg have the ideal design for industrial signature production in standard formats. One example is the new Speedmaster XL 106-P. Operating at up to 18,000 sheets per hour, its output would previously have been split between two or three folding machines to avoid postpress bottlenecks. Depending on the print job, the new principle of folding in a shingled stream and the PFX feeder now make it possible for a single TH/KH folding machine with just one operator to process the entire output of this high-performance press. Logistically speaking, the pallet feeder is perfect complement to the press. Stacks are transferred from the press directly into the folding machine's feeder. And high-performance Heidelberg delivery systems, especially the TSH Twinstacker with lateral pack output, offer operators sufficient buffer capacity for removing sheets from the folding machine and depositing them on the pallet, even at top speeds. Thanks to automatic stack jogging in the delivery and output on two levels, removal at high speeds is possible even without additional banding.