TechnologyStahlfolder TH 82-P: Streamfeeding in all Stations
Heidelberg's Stahlfolder folding machines were designed with an emphasis on their ability to fold various jobs economically with very short throughput times with consideration of production quality and cost effectiveness. The new TH 82-P model builds on that premise by offering:
- Speeds beyond 15,000 sheets per hour with a 50 percent increase in throughput for 16-page signatures, compared to industry leading single sheet buckle plate folding
- The same fold quality and versatility of substrates as with current processes as the linear speed remains constant in the comfort zone of conventional folders (below 170 m/min)
- Full versatility of a conventional buckle plate folder, as conventional folding schemes are being used, standard plates can be used in all units and the machine is portrait-fed
- True one-person operation with advanced pallet feeder and delivery
- Improved efficiencies in the bindery by matching one press with just one folder with annual productivity potential of more than 40 million sheets
Overall folding technology, in regards to increasing net output per hour to equal the pace of today's presses, has come to a crossroads.
The challenge is that with a linear speed increase it becomes more difficult to control the quality and consistency of the folds. The TH 82-P solves that problem. Heidelberg engineers addressed the linear speed of folding paper with streamfeeding, taking into consideration the paper grain and paper weights to significantly improve the net performance and quality.
The streamfeeding innovation takes place in all of the stations from the feeder onto the infeed registration table as well as the cross carriers on the second and third stations. Until this point, streamfeeding was only used in the infeed; applying it throughout the folder was considered too difficult to engineer. Yet exactly that enables the TH 82-P to manufacture 16-page signatures up to 15,000 an hour while the linear speeds remains in the comfort level of 150-180 meters a minute compared to the 10,000 that is being produced today with the same linear speed.
The engineering technology, developed by Heidelberg for the folder, enables today's customer to run 16-page formats at 15,000 an hour. This folding concept matches closely to today's presses. One long perfecting press equals one folder! Streamfeeding every station (the cross and the two parallel stations) is the hallmark innovation of the "P"-Generation folders: a shingle (i.e. an overlap) of up to half the sheet length enables a 50 percent higher throughput at the same linear speed; three sheets can now pass through each fold station at the same speed and time that it took before to process two sheets when producing 16-page signatures.
Air management separates the sheets or folded signatures in the fold plates. While one sheet is exiting the plate, the next one is already arriving. New pressing rollers integrated into the fold units create a sharper fold, thereby stabilizing the fold process even further. At the cross carriers for the second and third stations, each sheet is individually accelerated. Additional design changes allow the stream of folded sheets at the second and third station.
The TH 82-P allows the operator to keep the linear speeds in the conventional comfort zone (below 170 m/min) yet output is increased by simply turning to streamfeeding in all stations. Even lighter substrates will experience this productivity increase, all the while maintaining the same fold quality achieved before in the less efficient single-sheet operation.
Lean manufacturing principles are more important for printers today than before to minimize waste and drive as much high quality finished product as possible, realizing lower costs and higher profits. With offset presses running regularly 18,000 sheets per hour, bottlenecks in folding are prevalent. This drove the need for higher efficiency folding. The efficiencies of the new platform TH 82-P stream feeding innovations have numerous benefits. The finishing department has an increased net output by more than 50 percent. One Stahlfolder TH 82-"P"erformance with automation can replace two to three legacy inefficient folders with one and reduce labor overhead and the space needed for intermediate storage. In summary, the manufacturing process is shortened and a positive gain in the finishing process is realized.
In the overall analysis from the recently installed TH 82-P, the customers have seen an increase in net productivity of at least 50-67 percent on 16-page signature work. Customers with the TH 82-P are now running 15,000 sheets per hour with one operator, while their price per performance ratio on legacy equipment was around 5,000-9,000 an hour with one to two operators.