Suzanne Callander reports on some interesting robot applications in the confectionery production sector, looking at how challenges have been overcome and the benefits that robotic technology can offer.
While the use of robots is becoming more common in food manufacturing applications, they are still only used by a minority, with just one-in-ten food producers in Europe currently employing robot technology.
With plenty of room for growth in the confectionery sector, Martin Sauter, Director of Sales at Gerhard Schubert GmbH, believes that interest in robotic packaging solutions from confectionery manufacturers is increasing. Explaining why, he said: “Confectionery manufacturers today are having difficulty finding suitable human operators to undertake manual operations. Even if operators can be found, the cost of labour is rising.”
In addition, there is a growing need for greater production flexibility to meet ever faster-changing demands from retailers, so confectionery producers are always on the lookout for more flexible and efficient packaging solutions. “Our Pickerline and Flowpackers can meet the need for automated packaging solutions for medium or high-capacity production facilities,” continued Martin. These smart automated systems know exactly which products will be arriving in the packing hall on production belts, because they can be connected to, and communicate with, moulding, enrobing and other production processes.
“Today, sophisticated vision systems can recognise the products on the infeed belt and do a quality check before the robots pick and place the products into trays or flowpack infeeds,” said Martin. “The dimensions and the shape of products can be detected, in addition to other characteristics – such as height, colour or decoration. Pickerline’s and Flowpacker’s from Schubert ensure that only products meeting the confectioners defined quality standards make it into the packs.
“Last but not least, assortment packs, such as pralines – either for packed or unpacked products – can be produced automatically by the Assortment Pickerline,” said Martin. “Tray denesting, various product infeed systems, product vision inspection, turning stations to change the facing if required, careful product handling, cushion pad placing, guaranteed card feeding and placing, carton tray and lid erecting (either with or without glue) can be combined in one automated packaging line. This is cost-saving and efficiency boosting at its best!”
Training is key
Commenting on the important role that training plays in helping operators on the production floor work safety and efficiently with robotic systems, Uwe Galm, Director of Customer Services at Gerhard Schubert GmbH, pointed out that when it comes to high performance machines that include robotics, operators still have an important role to play in achieving performance targets. Offering advice, he said: “Operators need to be able to react quickly to events and make the right decisions without hesitation. To do this they need experience and knowledge which can only be achieved through appropriate training on the machine and the process – both in theory and practice. A variety of different learning methods are useful here. The mix can consist of classroom, onsite and online training. When designing a suitable training programme, the methods need to be focussed on the real needs of the given situation.”
Replacing space hungry conveyors
A few years ago, Austrian bean-to-bar chocolate manufacturer, Josef Zotter faced a challenge when setting up a new facility. “We were severely limited in terms of space and were looking for a compact but also precise solution,” explained Alexander Hödl, a technician at Zotter. Looking at a range of space-saving solutions, the company made the decision to employ robots supplied by Kuka, as part of its chocolate moulding operation.
Kuka supplied two compact six-axis robots, which are designed to work at high-speeds and are suited to use when hygiene is a requirement. One robot picks up the mould into which the liquid chocolate is to be poured and then moves to the pouring system to allow the mould to be filled. It then swivels the mould with extreme precision so that the chocolate is evenly distributed inside it, and places it in a refrigerator. This is where the second robot takes over – removing the cooled chocolate in moulds from the refrigerator and transporting them to the output conveyor, where the finished bars are removed from the moulds.
Many consider that the adoption of robots will put humans out of work, however the reality at Zotter was very different, where the space-saving solution has actually led to additional employees being hired to work with the robots, feeding clean moulds to the first robot in the system and removing cooled bars at the end of the process
“If we had chosen a setup with conveyor belts, not only would it have taken up much more space, but the work steps would also have taken longer,” says Alexander. “Now, with the flexibility that the robots give us, we can respond very quickly to specific customer wishes and we are also able to produce smaller order quantities.”
Zotter has also employed robots at its visitor centre – Zotter Experience World – which includes a theatre, cocoa roastery and tasting areas. Here two six-axis robots, fitted with suction cups, serve customers with their chosen chocolate treats. Customers make their selection, via a touch screen panel, and the robots pick their choice and serve it to them – providing further entertainment by doing a dance to music too! A bit of fun maybe, but it does offer a good demonstration of robot capabilities.
Secondary packaging solution
Nutresa México is another a proponent of robotics – using them within the packaging lines for its Muibon and Cremino chocolate bars. Cremino is a praline made of hazelnuts and cocoa while Muibon is a wafer filled with hazelnut cream, covered with chocolate and peanuts.
Nutresa Mexico has been working closely with packaging machinery company, Cama for the last ten years. “We know their machines well, which provided us with the assurance we needed when the time came to acquire new packaging solutions for our Cremino and Muibon lines,” says Carlos Toro, Operations Manager at Nutresa Mexico.
The company faced several manufacturing challenges. The first one was to increase productivity – to create more product output for a specific number of man-hours. The second challenge consisted of removing the pressure of these additional products on the workforce at the end of the lines, which was very labour-intensive, particularly for the packaging process. “This compelled us to explore new alternatives for the Cremino and Muibon packaging processes,” says Carlos.
A decision was made to automate the secondary packaging operation on one of the two Muibon lines and the Cremino line, using Cama robotic solutions. “These machines enable us to pack our chocolate bars in different formats intended for different channels –wholesalers, supermarkets, and membership-only retail stores. The solution provides the flexibility to achieve all these all these different formats,” says Carlos.
During the rollout process for the automated packaging solutions, there were some hurdles to overcome, as Carlos explains: “It is critical to synchronise the new machines with the existing solutions implemented in the line to thermoform the trays where chocolate bars will be deposited. Furthermore, this process needs to be undertaken with the highest possible speed, to keep pace with four machines that wrap chocolate and feed the Cama Group machines. “Fortunately, we found a solution that ensured everything worked properly.”
During the process Nutresa Mexico had the support of two Cama Group technicians for two weeks, who helped with the implementation and also offered training sessions for the maintenance teams to ensure that they understood the operating principles of the machines.
The secondary packaging process now employed is simple. For Cremino, the Nutresa Mexico teams thermoform the trays, a Cama Group IG270 model unit takes those trays from a feeder and by means of robotic arms, grabs the chocolates transported on belts, and puts pieces on the trays. The IG270 is an automated loading unit that includes two small footprint robots with carbon fibre arms suited to fast product handling applications and an intelligent vision system that allows the robot to sort and pick loose products in a production line and puts them in a container, box, or conveyor in any preset pattern.
The Muibon line now employs a Cama Group IF296 unit – a high-speed monobloc machine that utilises robotic units to assemble, load and wrap boxes and which can also handle wrapped products and flowpack. This unit assemblies the display-box that contains the wafers, loads the wafers inside the box, and then seals it with hot glue.
The machines offered the company the flexibility it needed to package a variety of different formats. “It was also important that the equipment complied with all necessary regulations relating to risk, and contamination. We also wanted machines that would ensure operator safety when working with the equipment. Accordingly, both machines are supplied with enhanced security, with stainless parts and safety guards to avoid the risk of entrapment.”
There were more positives for Nutresa Mexico. Its global efficiency, measured with the Global Efficient Equipment, has risen from a global efficiency of the line of 84% to 86%. Furthermore, the installation of the Cama Group machines has resulted in a 14% increase in line productivity. This translates into the production of 300 chocolate bars per minute for Muibon. Since there are two lines, that means 600 units per minute at the Nutresa Mexico plant. The Cremino line is now able to produce 1,080 units per minute.
With figures like these it should come as no surprise to hear that Nutresa Mexico plans to acquire additional robotic machines to continue to automate its chocolate production lines.
When hygiene is key
Of course, one of the most important considerations when looking at employing robots in confectionery production applications will be hygiene and, as robots continue to move further upstream into the manufacturing processes, the requirements for cleanliness, hygiene and food safety become more stringent.
From a hygiene and cleanliness perspective, the use of robots can eliminate the potential opportunities for human-borne sources of contamination during product handling. However, the type of robot used, and its design characteristics, needs to be given careful consideration to ensure the highest standards of cleanliness and food safety are maintained in hygienically sensitive environments.
A collaborative study undertaken between the European Hygienic Engineering & Design Group (EHEDG), ECOLAB (Minneapolis, MN) and Stäubli Robotics – known as the Humid Environment (HE) Project – set out to achieve technological advances to elevate the standards of hygiene for robots used in sensitive environments to the highest level.
A primary objective of the project was to consider the potential sources of contamination, and how best to eliminate them. This included a detailed review of the mechanical elements of the robot and how the working environment and temperatures could influence the generation of contaminates.
The study took into account multiple factors including robot arm design, potential for bacterial contamination, retention zones, dielectric exchanges between cleaning solutions and the various metals used in the arm construction and surface treatments
Of the three main types of robot used within the food-manufacturing sector – Delta, four-axis and six-axis, the Delta configuration was found to hold the greatest potential for contamination. The architecture of this type of robot means that its motors, transmission oils, retention zones and the overhead mounting frame itself, are all located directly above the food product.
The report recommended that any parallel (or Delta) architecture robot design due to be employed in sensitive food production areas should be covered to prevent possible contamination.
Another consideration highlighted by the report was that during operation a robot can heat up to 70°C – especially when installed within a high-speed line. In sensitive environments, where operating temperatures range between 4°C and 10°C, condensation, oil expansion and cooling off can occur within a few minutes. The effect of the heat generated by the robot is most noticeable when the robot reaches the end of the production cycle.
Food for thought
According to the International Federation of Robotics, new robot installations across all industries is expected to rise by around 6% per year, with reductions in cost and improvements in technology creating additional opportunities to implement robot solutions. I hope that we have offered you some food for thought about the use of robotics on your own production lines. While the majority of robot applications are still mostly found in the packaging hall, the reduced cost, greater ease-of-use and technological advances will surely lead to more applications for robots being found throughout confectionery production lines as the need for more flexible and cost-effective solutions continues to grow.
Editorial contact:
Editor: Kiran Grewal kgrewal@kennedys.co.uk
