Hunkeler has developed a splicing unit for non stop printing of finishing of inkjet printed reels. The RX8 will be shown at Hunkeler Innovation Days in Lucerne at the end of February.
The development addresses an Achilles Heel of continuous feed inkjet printing, that when a reel is finished the press must stop to load a new reel. Solutions are available from Tecnau and Contiweb, but have not yet proved popular. However, for inkjet to offer a truly effective challenge to litho, this issue needs to be tackled. The RX8 will, says Hunkeler, lead to a productivity gain of up to 30%.
The system has two reel stands in a tandem configuration with the web feeding from between the two. A festoon array can be filled as a reel change nears, allowing the web to be stopped to carry out the splice. A double-sided tape is used to bring the two webs together.
Hunkeler has designed a trolley to deliver the reel to its stand with an air shaft to lock the reel into the fixed arm at one side and a swing arm at the other. Unloading involves lowering what is left on the reel and unlocking the swing arm. The trolley can then be withdrawn ready for the next reel.
As well an enabling continuous running on the same paper type, for book production for example, the RX8 can operate reels of different paper types if this is within the capability of the chosen press.
There are two versions: the RX8-500 able to run at 152m/min and the RX8-800 to run at 250m/min. It can operate with paper from 60-150gsm and a web width of 559mm.
Hunkeler will demonstrate the media changer in one with a book block line which has also been enhanced for increased productivity. This can deliver four-, six- and eight-page signatures using a plow folder system which can changeover in seconds while the festoon buffer zone is filled without stopping the press if running inline or the unwind if in a near line set up.
Book block stacks are delivered in piles up to 120mm high, delivering 600 stacks an hour.
The book block line will operate with a 76cm wide web, though not with the non stop media changer. It might be a matter of time before the RX8 is offered with a wider web option.
