Automated finishing

Finishing systems specialist Werosys has installed differently configured machines at two Danish converters which demonstrate the range of options available in its high-end modular Concept systems.

Werosys was formed almost four years ago with a clear focus on automated and integrated finishing systems based around the twin concepts of Cloud computing and Industry 4.0.

‘Where for most companies software is installed on top of mechanical systems, for me it was the other way round,’ says Bjarke Nielsen, chief technical officer and founder of Werosys. ‘I am driven by solving things by software first and then adding the mechanical layers. When I design a machine I see it from the computer’s point of view, as an IT platform.’

The goal is for the machine to run itself using information stored on remote servers. ‘For example the machine will always run at its optimum speed without external input from the operator, who simply turns the dial to maximum. Software modules communicate with each other, telling one process to wait while a slower process happens, so the machine works out its own bottlenecks while always protecting itself.’

The Werosys Concept machines are embedded into Cloud/Industry 4.0 systems, meaning all aspects of the machine down to individual electrical components can be monitored in real time.

‘All our components are designed from the ground up to 4.0 requirements, so the amount of information we can get back about the machine’s condition – Big Data if you like – is huge. If a motor starts running hotter you can look back and see when it went wrong, and anticipate breakdowns before they happen,’ says Nielsen.

The use of servos throughout the Concept machines eliminates problems associated with brakes and clutches. ‘A servo motor is an intelligent motor which can have a lot of behaviors depending on how you program it. It can accelerate but also act as a brake, and can be monitored with built-in sensors.’

Nielsen describes Werosys machines as like ‘Lego lines’. ‘Each of our modules is itself modular, so we can move rollers around and change web paths, for example.’

With label converters’ profit margins under such pressure, Nielsen sees automation as the only way forward: ’Why is the operator setting up how many labels, choosing cores and other manual steps which are already in the customer specification and therefore in the customer’s IT system?’

Setting up automation between IT network and Werosys finisher is easier than many converters think, says Nielsen. ’It does not require a complex MIS system. The file exchange is done in the universal XML format which sets the machine up directly, so the only manual step is for the operator to place the core on the mandrel. The operator does not have to know how the job is printed – digital or flexo etc. He scans the barcode on the order and our machine then fetches the job ID. The XML file says how many labels per roll and how many lanes and the slit width.’

The barcode does not hold the actual job information – instead it points to a location on the server. Therefore the machine set-up always reflects the latest changes on the IT system.

The Concept’s control system is based on industrial Windows, giving the stability of an industrial hardware platform with the benefits of a Windows interface. ‘So we can access a server just like a standard PC, at the same giving us more power than a PLC controller so we can solve problems in software that for others require hardware.’

Dittokan

The first Werosys installation visited by L&L was at Dittokan, a small but ambitious converter located in Aarhus, Denmark.

The highly specified Werosys line was designed around a Xeikon 3500 digital press and demonstrates all the advantages of automation outlined above.

The digital converting line is 550mm wide to match the press width. The first part of the installation saw Werosys take over web handling for the Xeikon press with a dedicated unwind with web guide and web cleaner into the press. After printing, a second web guide takes the web into an in-line flexo printing module with lamination and cold foil options, and from there to a rewind.

The printed web is then removed from the press and placed onto the Werosys Concept finishing line. After the unwind and web guide, the web passes through a series of converting modules. These include a laser die-cut station; a fully automated slitting station; a turret rewinder, a rotary sheeting/ die-cutting system and a semi-rotary/full rotary die-cutter running at speeds up to 90m/min and 500m/min respectively.

On the automated slitting module, each knife has a dedicated motor, allowing job changes to be carried out on-the-fly, without stopping the web.

The Concept finishing line allows Dittokan to run multiple jobs in the same roll on the Xeikon press then separate them on the converting line – greatly increasing output from the digital press.

The configuration of the Werosys Concept requires the digital press to print a barcode in between each job, and the line then reads the job ID from the barcode and extracts job data from the customer’s IT system. This data is used to re-configure the entire line for the next job on-the-fly without stopping the web. Jobs from the company’s flexo presses can also be automatically set up and finished on the Werosys line, simply by the operator scanning the Job ID from the work order.

‘We are a small converter and when we decided to go digital, the question naturally was “how can we be different than all the other converters which also have digital presses?’’, says Nicolai Svendsen, owner of Dittokan. ‘We decided the answer was to be the most efficient, and for that reason we started a long term project with Werosys to install a custom-built digital web handling and converting line. We still have a long way to go, but already the efficiency savings are clear.’

Flexiket

The second installation visited by L&L was Flexiket, today part of the Limo Holdings group, one of Denmark’s leading label converters.

The Aarhus plant visited by L&L contains a mix of conventional and digital presses, and specializes in print-on-demand and short run work. On the digital side there are two Xeikon 3300 presses and one EFJ Jetrion UV inkjet press. Another specialty for the company is screen-printed toy, hazard warning and chemical labels. Production manager Mogens Brinck was brought into Flexiket in March 2014 from Amcor Flexibles to help professionalize what was then a family-run operation. He is a long-time advocate of Lean manufacturing and is strongly supported by Limo group’s new CEO, who comes from outside the labels industry ‘and is always asking why something is not automated when it could be.’

The Werosys Concept machine at Flexiket is configured as a highly automated slitter rewinder, designed to reduce set-up time and increase throughput on delicate materials and small volume jobs.

The line is fully integrated to Flexiket’s IT structure. Each roll contains printed barcodes which reference job-specific data held on the server. This data sets up web tension, the automated slitting unit, and the turret rewind, all without operator involvement. The fifteen slitting knives can be set in less than 20 seconds.

Because the slitter rewinder is optimized to work with flexo printed material, where there is typically only one job per roll, Flexiket chose an automatic slitting system, where the knives are moved by a single motorized arm, working in close sync with an automatic turret to significantly increase efficiency. On the Dittokan machine, by contrast, all the knives have their own individual motors to allow on-the-fly job changes while the web is moving.

‘This machine was a big change for us, and now the operators really like it,’ says Brinck, ‘They simply have to scan a barcode and the knife setting is fully automated. The machine’s precise web handling control allows us to slit and rewind very delicate materials at speeds of 325m/min.’

Adds Bjarke Nielsen, ‘It is because of the machine’s PC-based hybrid controller that we can run stable tension at a high speed with a “super sensitive” dancer arm system and finish rolls well below 100m in length fast and efficiently. The software is calculating the control parameters for the servo systems at a rate of more than 1,000 times per second. At 325m/min we re-calculate everything for every 5mm of material running through the machine.’

This Concept slitter-rewinder installation was a joint development between Flexiket and Werosys, allowing this versatility to be programmed from the outset. ‘To handle different tensions at high speeds and on a range of materials has taken a lot of resources and operator involvement,’ says Brinck. ‘But on most materials we are now running at more than 300m/min and even operators new to the machine are making it sing.’