By Rob Bosman, Senior Sales Manager at Contiweb
I regularly speak to potential customers who think that an investment in non-stop winding equipment will only pay for itself in the case of huge volumes or digital printing presses with a wide web width. Together with customers I have made dozens of calculations and almost always we come to the conclusion that non-stop is also interesting for them. In this blog I explain why.
But first, what is non-stop winding actually? As soon as a paper reel is completely unwound and empty at the beginning of the press line, it has to be replaced by a new reel to be able to continue production. If you have a manual unwinder, the process of changing a paper reel consists of roughly 10 steps (see infographic). Some of these steps can only be carried out when the printing press is at a standstill. This causes a 15-minute loss of time per reel change, i.e. one reel change per hour means a 25% loss of production capacity. Add another 10 loss if you have a manual rewinder at the end of the press line.
With Contiweb's non-stop unwinder and rewinder you can change paper reels without having to stop the press. The machines have space for two paper reels. As soon as the paper reel on which has been printed is nearly empty, the buffer above the reels fills up with paper and the almost empty reel is stopped. The paper is cut off and glued to the new, full paper reel. The splice is ready before the buffer is used up, allowing the press to continue printing without stopping. There is only a short stop of printing when the splice is fed through the print units. This all happens in a time frame of about 6 seconds. The operator's work is limited to removing the old, empty core and inserting the new paper reel. This only takes a few minutes and can be done during printing.
The investment associated with the purchase of non-stop winding equipment is often recouped faster than expected. The operating costs of a web inkjet printing press quickly amount to several hundreds of Euros per hour and you can only recoup these costs if the press actually prints - not if it stands still. In addition, time is freed up for the operator to do other work.
I often hear that there are 2 operators working on 1 digital press when there is a reel change. One is doing the reel change at the unwinder and the other is doing the reel change at the rewinder in parallel. With non-stop winding, one operator can get the job done and also faster and without stopping production. This results in enormous cost and time savings.
I have also seen customers who have reached the limits of their production capacity and have considered solving this by working in shifts. Thanks to the investment in non-stop winding equipment, their production capacity increased significantly and they are still working day shifts.
Frequently, non-stop winding provides even more benefits. As soon as changing paper reels is no longer a time-consuming obstacle and you can change reels to your heart's content, you turn a weakness into a strength. For example, you can set up the non-stop unwinder with two paper reels of different web widths or coatings. The unwinder can splice these together without any problems, so that you can switch papers without annoying interruption. At the end of the press line, the Contiweb non-stop rewinder can do the same trick, so that the jobs are neatly separated and rewound on the correct reel.
Our machines are fully compatible with all brands of web inkjet presses. They can be built into existing press lines and can be recouped even faster for new projects.
If you are curious to find out whether an investment in this type of machine is of interest to you, use the handy calculator below. On the basis of a number of data that you have to fill in, the calculator gives an indication of the number of annual production hours that you can recover by investing in Contiweb non-stop winding equipment, and of the payback time. This allows you to quickly determine whether the investment is worth your while. Or feel free to contact me to discuss your specific situation. We often come to surprising conclusions!
By eliminating an enormous number of lost production hours when using manual winding equipment, non-stop winding equipment normally pays for itself very quickly. Use the calculator tool below for an indication of the payback period and determine whether you can benefit from non-stop winding.