For carton converters, time is money. The faster they can convert folding boxboard to cartons and the fewer disruptions they face in the process the better their business performance will be. Just as important as speed are the need to maximise quality and minimise waste – but until you put a board on your converting line you never really know how it will perform and what kind of challenges you might be faced with. This is where in-depth trials and analysis come in.

Valuable insights to optimise converting performance

“These kinds of studies provide critical information both for us as a paperboard supplier and for our converting customers. We gain valuable insights into how our paperboards perform in the real world and our customers benefit from expert support to optimise the performance of their converting process according to the raw material they are running,” says Lauri Järvinen, Technical Marketing Manager at Metsä Board.

Optimising a converting line is not a task for beginners; each and every step from printing to die cutting and gluing requires careful adjustment to ensure good runnability of the board, high-quality print results and proper folding. Without this optimisation the result would be a costly pile of wasted paperboard.

“We work closely with our network of partners, which includes ink suppliers, machinery manufacturers and glue manufacturers to ensure that we have the best information available to tackle any challenges and produce the best possible end result for our converting customers,” Lauri explains.

Smart procurement decisions improve sustainability

The latest study was conducted in collaboration with Pyroll Packaging at their Tampere Plant in Finland. The purpose was to investigate the converting performance of MetsäBoard Pro FBB OBAfree against comparable paperboards – including a white lined chipboard (WLC) made from recycled fibres. The end product was a carton for oat flakes.

“Many brand owners and consumers automatically assume that recycled board is more environmentally friendly, but that may not always be the case,” Lauri highlights. “You always need to look at the big picture and not just the individual parts of the value chain. For less demanding applications recycled board can of course be an excellent choice, but for more challenging applications you may end up with runnability issues, poor folding and poor-quality end products. This costs money and wastes large quantities of valuable board, which is not ideal from an environmental perspective.”

In the converter plant trial it was shown that Metsä Board’s fresh fibre paperboard could be run at speeds 30% faster than the WLC product and that blanket washing only needed to be performed every 9,000 sheets as opposed to every 6,000 sheets with the WLC. “Faster production with fewer disruptions translates into a healthy bottom line for the converter,” Lauri points out.

About 6,500 kilos of Metsä Board paperboard were needed to complete the production run as opposed to around 9,000 kilos of WLC. And in terms of waste throughout the entire converting process, Metsä Board’s product had a waste factor of less than 4% compared to approximately 16% for the WLC. “The opportunity to use lighter grammages is another significant advantage of fresh fibre paperboard because lighter weights mean less board is used in total and less needs to be transported, which of course reduces CO2 emissions in the logistics value chain,” says Lauri.

Looking beyond the price tag

While fresh fibre paperboard can be the more expensive option up front, converters can quickly claw back that initial outlay by saving time, weight and waste. This is not to say that recycled boards do not have a valuable role to play. “There are many applications where recycled boards are an ideal choice, but it takes a little more effort and understanding to be able to handle them properly,” says Lauri. “It’s also important to remember that without fresh fibre board there would be no fibre available to make recycled board in the first place.”

Metsä Board’s converting efficiency study showed us how premium lightweight fresh fibre paperboard can improve efficiency in folding carton converting. Metsä Board’s folding boxboard clearly performed with higher efficiency than the corresponding recycled paperboard.” Jani Markkanen, Production Manager, Pyroll Packaging Ltd, Tampere Plant