Better packaging means better access to medications and food. Today, a third of the world’s food still goes to waste, often as a result of inadequate packaging and storage. The pharma segment is also one of the drivers, with dynamic annual global growth of around 9%.

At the same time, more complex substances and the ever-stricter requirements of manufacturers and lawmakers have placed growing demands on the packaging industry.

Typical applications include

• Form/fill/seal machines
• Labellers
• Case packers
• Carton and case erectors
• Baggers
• Bundlers
• Shrink wrappers
• Smart belts
• Indexing tables

Key challenges

• Shorter design times
• Quicker changeovers
• Handling broader material ranges
• Higher throughput
• Improved line integration
• Safety

Traditionally, we view automation as a means of making high volume manufacturing processes more efficient. We visualise production lines running fast and efficiently with minimal human intervention.

But automation also enables a processing system to be adjusted with a quick change of menu options on a control panel, making viable smaller and smaller batch numbers. Such flexibility is essential in the face of evolving consumer preferences – new tastes are arising due to health consciousness and cost. We now have organic, gluten-free, sugar-free, low-fat, high-fibre, low-sodium and caffeine-free variants of many products. Food firms and retailers demand a broadening range of portion sizes and packaging formats.

Primary packaging is the most challenging task in the packaging industry. In these machines, the packaging material meets the product at the highest possible speed; as a result, the level of precision has a direct influence on both product quality and the usage of raw materials. Designed for maximum flexibility, lines also feature fast product changeover speeds, from smaller on-the-go packages to larger family packs. The lines feature horizontal flow wrapping and secondary packaging equipment.

High-speed packaging machine functions like code stamping and bad product rejection must also be synchronised with motion control to achieve absolute precision. Much of the next wave of productivity enhancements will come from information that can be accessed from the HMI and across the entire packaging line.

Electronic drive technology

Packaging machines belong to one of the most drive-intensive sectors of the machinery industry. In Germany, according to Quest TechoMarketing, they rank second for this across the 10 machinery sectors and packaging machines are responsible for 16% of the total implemented electronic drive technology, and it is growing at around 9% per annum. The vast majority of electronic drives used in packaging machines are AC inverter drives, with small shares for DC drives and linear drives. The survey also notes that packaging machine builders rarely use servo drives with integrated PLC.  

Control cabinets

One characteristic of conventional packaging machines is the large control cabinet outside the main structure of the machine. The controllers within this cabinet are connected to the drives, sensors and valves by a multiplicity of cables and lengths of tubing several metres long. An interesting trend is to reduce the machine footprint by integrating the control cabinets with the electrical and pneumatic components into the machine itself, such as the pedestal angles. Such a compact machine footprint helps to minimise cabling and makes it easier to access the utility devices.

Designing and building a modern control panel is complex and time consuming. Not only do panel builders need to meet tighter international and local regulations, but there is constant pressure on improving time-to-market and maintaining competitiveness. At the same time, they face serious labour shortages, particularly of skilled workers. As more functionality is squeezed into already tight designs, the number of devices used in control panels is increasing. And the trend is to reduce sizes or to squeeze more functionality into existing panels.

Moving to standard component heights, downsizing components, easy wiring insertion systems and electronic data libraries are some of the available remedies. Many of these factors point towards working with a single component supplier as far as possible, but a conflicting issue is the desirability of integrating automation components from a range of suppliers.

Applicable standards

There was a time, perhaps 20 years ago, when international standards did not allow for the level of integration and connectivity now desired, because the technologies did not exist. Specifications from this era are simply no longer relevant.

In control programming, the IEC 61131-3 standard has quietly emerged over the years as the accepted global standard. The IEC 61131-3 is a standard defining the programming languages for PLCs, embedded controls, and industrial PCs, harmonising applications independent from specific dialects, but still based on known methods such as the textual programming languages Instruction List, and Structured Text, the graphical programming languages Function Block Diagram and Ladder, and the structuring tool Sequential Function Chart.

PLCopen is an independent organisation whose members specialise in industrial automation. It was founded in 1992 just after the worldwide programming standard IEC 61131-3 was published. The controls market at that time was a very heterogeneous market with different types of programming methods for many different PLCs.

Work is concentrated around technical specifications pertaining to IEC 61131-3, creating specifications and implementations in order to reduce cost. Outcomes include standardised libraries for different application fields, harmonised language conformity levels and engineering interfaces for exchange. Experts of the PLCopen members are organised in technical committees and define open standards with end-users.

Today, IEC 61131-3 is a highly accepted programming standard and many industrial software and hardware companies offer products based on this standard, which in the end are used in many different machinery and other application fields.

This programming approach is entirely compatible with the concept of HMI templates and accessing user-serviceable elements of the control system from the HMI. It’s also consistent with recipe-based control systems in which pre-programmed recipes are selected from the HMI, and where parameters can be adjusted to run different sizes, flavours, and shapes of products — all without altering the program.

Software also helps OEMs configure and program packaging applications that require precise synchronization, camming, registration, electronic gearing, collating, robotic path planning and dynamic belt synchronization. Open architecture programming environment also supports the use of OMAC packaging guidelines like PackML  (Packaging Machine Language), an industry technical standard for the control of packaging machines. The primary objective of PackML is to bring a common “look and feel” and operational consistency to all machines that make up a packing line

The use of OMAC PackML and communication of multiple control platforms over the same network and protocol, avoids the need for a line PLC to coordinate the equipment. This meets the need for packaging line owners to ultimately demand greater interoperability of industrial networks, if not for individual machine controls, then for machine-to-machine and machine-to-management systems communications. For communications that do not require determinism, TCP/IP and OPC suffice. For line control networks to synchronize production flow and better balance the line, and for new applications such as networked safety, there must be a better way.

Sadly, there is no universal device bus or industrial Ethernet. This played out in the 1990s, when regionally dominant suppliers created de facto standards in their respective markets. The situation was as if Apple and Microsoft controlled Internet access instead of true standards such as HTML.

As a result, a large number of controls suppliers now support all major flavours of industrial Ethernet, whereas others recognize only their own protocols. The irony of this situation is that the latter make it artificially difficult to communicate over a third-party network, while the former can readily communicate in a multi-vendor environment regardless of the network.

Applicable standards

Robotics is one of the fastest growing markets within the packaging industry. Compared to a decade ago, robots are faster, more reliable and more affordable.

Easing and speeding the implementation of robotic packaging systems through software is a subject that is dear to the hearts of all the major automation vendors. It allows machine builders to develop their controls faster and more efficiently for their specific application through …parameterization, instead of programming. It includes integrated IEC 61131 compliant ready-made robotic Function Blocks and other application-specific technology functions that can help reduce routine work.

Many packaging machine builders are investing heavily in integrating robotics into their machines, rather than building a machine around a stand-alone robot with its own black box controller, innovative OEMs are integrating the robot designs into their machines and controlling the entire machine with a single, programmable controller. The increase in performance and productivity combined with simpler controls interfacing has brought the ROI/payback to a level that is able to be justified by more end users.

The intended result is higher performance and a system which is easier to program, commission and service.

Traditional programmable controllers (PLCs) are also being replaced with PC-based control, because of their ability to easily implement picking algorithms at the sub-millisecond speeds which are now demanded by contemporary state-of-the-art robotic packaging.

PC-based control systems can cost-effectively replace expensive dedicated robot controllers with an off-the-shelf controller and standard software that can actually control the entire machine, including the robotic portion of the application.