Digitising paper sack production

A completely digital paper sack production line recently introduced by Windmoeller & Holschen has demonstrated its ability to improve both quality and productivity

Technical solutions using software and microelectronics are replacing conventional, mechanical and analogue systems in paper sack production. Having already automated all areas of paper sack lines directly related to production, Windmoeller & Holschen has taken the next step by introducing ‘smart’ automation solutions to production planning. Said to be the world’s first completely digital paper sack production line, W&H’s new automation solution is digitally connected via a local area network (LAN) and features digital control, drive and pasting technology.

During its launch at customer MONDI’s facility in Trebsen, W&H demonstrated that digitally linking machinery for each step of the production process (tube forming, conveying and tube storage, sack production and palletising) via ethernet can boost productivity and flexibility while reducing waste.

In addition to introducing digital integration, a further increase of production speed to 360 bpm was demonstrated along with several new features designed to improve productivity.

Digital pasting celebrated its debut in 2008 with the launch of the AD 8330 bottomer. Since then, W&H has sold seven of these machines to customers around the world. In Trebsen W&H complemented the digital bottomer with a tuber of matching technology: the AM 8135.

Three key elements contribute to the success of digital pasting: contact nozzles, glue management and an intuitive operator interface. Contact nozzles apply paste reliably and with utmost accuracy even at speeds above 350 m (1150ft)/min.

Advanced glue management

The highly advanced glue management system guarantees the quantity of paste applied remains constant, regardless of machine speed or flow properties of the adhesive. At the heart of the system is an intuitive user interface which simplifies operation of this cutting edge technology.

Product and size changes during the demonstrations highlighted the line’s advancements in flexibility and efficiency. The changeover of seam pasting in the tuber from starch to dispersion glue – including rinsing and refilling of the system – took less than one minute.

Changing the cross pasting from a straight edge to a complex contour was equally fast and simple. Pasting precision was shown at all speeds, which is not just an improvement of optical quality but significantly boosts bottomer performance.

Increasing productivity

Digital pasting on the AD 8330 bottomer was no less impressive. With a few taps to the touchscreen, the operator changed bottom- and bottom patch-pasting patterns while the machine was running. Size parts have become a thing of the past.

The creation of the EASY-FLOW material handling system was driven by the concept that optimising the interaction of individual machines in a production line will increase overall productivity. EASY-FLOW extends the functionality of traditional material flow systems to include automatic management of storage volume which was designed to maintain storage content at an optimum level at all times.

It used to be that the bottomer would slow down or stop altogether when the contents of the tube storage decreased. With EASY-FLOW, a signal is automatically sent to the tuber to begin producing more tubes; when storage levels increase, the bottomer is signaled to produce at a faster rate.

Additionally, the system gives machine operators more transparency than ever before. For example, during job changeovers, space being used on the conveyors is shown graphically for both current and upcoming jobs.

With this new state-of-the-art technology W&H showed that perfect synthesis between advanced machinery and modern information processing can increase the competitiveness of paper sacks in the packaging market.

New technology

One visitor to the demonstration at MONDI Trebsen commented: “W&H has once again raised the technological bar.

“The company uses extraordinary productivity and new technology to address the needs of the industry and to support paper sack manufacturers in developing their businesses.”

This newly reached level of technology is expected to have far reaching effects on the paper sack industry.

Windmoeller & Holschen

T: +49 5481 14-2929