The tasks for a sorting station for banknote sheets are diverse and complex. This configuration shows a realised example of an MSP with a sheet feeder with manual nonstop and inspection options for transmitted-light inspection and inspection of the sheet top and sheet bottom, and it also features 3 sheet stackers.
The sheet alignment is followed by the TLI transmitted-light inspection module. Here, watermarks are typically inspected in the UV wavelength range. This is then followed by the inspection table for sheet inspection from above, which is then followed in turn by the overhead table for inspection of the rear of the sheet. At the overhead table the sheets are freely accessible, which means that no areas need to be excluded from the inspection. The camera systems – typically for the visible and IR wavelength ranges – are mounted directly on the inspection tables.
The 3 sheet stackers can either be used for sorting based on different criteria, or 2 sheet stackers can be used for non-stop operation and the third for ejecting defective sheets. The conveyor to the sheet stackers is designed a way that allows code readers to be installed, which then detect the sheet number and thus enable a seamless track-and-trace system.
The MSP is equipped with a sensor system that not only detects double sheets and checks the sheet alignment, but which also detects sheets that stick together at the end of the sheet. Sheets that do not have perfectly cut edges can get caught up in each other. These linked sheets do not form a double sheet and therefore cannot be detected by a double sheet detector. As a result, sheets can make their way undetected into the sheet stacker. With the aid of the integrated sensors, these sheets are detected and the required alarms are triggered.
Another configuration option for the MSP 106 is in conjunction with the MABEG cross cutter RS 106.
In sheet-fed printing houses that concentrate on certain business areas, more and more reel sheeters are being used on sheet-fed offset printing presses. The compact and open design and the exceptional ease of handling of these in-line reel sheeters enables even typical sheet-fed printing houses that do not have any specific reel expertise to work from reels. In addition to quieter running and more cost effective materials purchasing, another advantage here is the shift of value creation from the paper mill to the print shop.
Banknote printers thus have the option of being able to implement security features in the sheet on short runs, which would be impossible or very difficult to offer from the paper mill on account of the generally increased workload and complexity of the reel process.
For the processing of reels, the line works in reel-to-sheet mode and cuts the reel accurately to the required register, e.g. the watermark. The finished stacks created this way inside the print shop have been inspected and sorted, and of course they can also be furnished with sheet coding for installed track-and-trace systems. In just a few minutes, the line is then switched over to sheet-to-sheet mode and serves as a sheet inspection and sorting line.