Baking biscuits better

Arnott’s has upgraded its Adelaide manufacturing plant to make its biscuit production more flexible and productive.

Millions of Australians have grown up with Arnott’s over the past 152 years. For them, Arnott’s is more than a food company — it’s a piece of Australia’s history and a national icon. Arnott’s portfolio of brands includes household names like Tim Tam, Shapes, Iced VoVo, SAO, Vita-Weat, Salada and Tiny Teddy.

As one of the largest food companies in the Asia–Pacific region, Arnott’s currently employs around 2200 people in Australia plus several thousand people across the Asia–Pacific region, in countries such as New Zealand, Indonesia, Malaysia, Singapore and Japan. In the last century more than 50,000 have worked for the manufacturer.

In its manufacturing plant in Adelaide, Arnott’s produces approximately 10,000 tonnes of biscuits annually. To meet increasing local and global consumer demand, Arnott’s recently embarked on Project FLEX — a control and HMI system upgrade to deliver increased flexibility and agility for biscuit production.

Agility and flexibility

When embarking on Project FLEX, Arnott’s had no hesitation in calling on its longstanding automation and control provider SAGE Automation. According to Stuart Mitchell, Senior Systems Engineer at SAGE, “We have been working with Arnott’s in Adelaide for the past 20 years so we are very familiar with the plant. It is a Rockwell Automation site through and through, so we naturally called on them to help with the upgrade.”

With expansion into international markets and a subsequent demand to increase production, it was important for Arnott’s to have the ability to run any biscuit on any line while maintaining product consistency.

The first stage of the project involved updating the legacy oven conveyor’s PLC hardware to improve the way that operators could load new production orders, including a feature that allows different recipes to be stored, selected and produced on the same line. It also involved the installation of two new cooling systems for conveyors including reprogramming of the control system and HMI.

The control system upgrade required the migration of legacy SLC controllers to Allen-Bradley ControlLogix to help reduce maintenance costs and allow for increased flexibility on production lines. While justifying the risk and expense of control system upgrades may initially seem like a challenge, investing in modern technologies that leverage the Industrial Internet of Things helps manufacturers realise the benefits of smart manufacturing.

As Jonathan Footman, Solutions Architect, Rockwell Automation, explained, “The more connectivity you have across the plant floor helps implement the technology to enable smart manufacturing and progress in the journey towards a connected enterprise.”

Keeping the plant running

To keep the plant running, Arnott’s leveraged the inherent flexibility of the Rockwell Automation Integrated Architecture system to undergo a staged migration to the new controllers.

The ControlLogix control system offers modular architectures and a range of I/O and network options. Tight integration between the programming software, controller and I/O modules reduces development time and costs at commissioning and during normal operation. To help reduce engineering time, SAGE used existing SLC I/O in the first stage and subsequently added some Ethernet Point I/O and Flex I/O on DeviceNet. The RSLogix Project Migrator tool was used to install the ControlLogix controllers with ease.

“While the majority of the plant uses Ethernet, there is still some equipment communicating through DeviceNet and DH+ so by using ControlLogix, any potential integration issues were overcome because the controller is compatible with all three networks. This flexibility allowed the upgrade to be performed in a staged manner as opposed to having to perform the whole upgrade in one go,” explained Footman.

Reducing production loss during an upgrade is often filled with challenges, but in this case, thanks to careful planning and a phased approach to the migration, the upgrade was completed with no production loss.

SAGE designed, programmed and installed the HMI solution allowing for a large number of recipes to be created and stored for each oven.

Driving flexible biscuit production

Delivering a wide range of motor control, Arnott’s installed seven new PowerFlex 525 drives as part of the upgrade. SAGE was responsible for the drive integration using existing code to both new and existing Ethernet and DeviceNet networks. Moving to the newer platform increased the operational efficiency and centralised the plant’s control system.

In addition, Arnott’s leveraged the intelligence of the PowerFlex variable speed drives on ethernet to help operators access real-time information in the plant. “Prior to the drive upgrade, the operators would have to run feedback using analog set points, which was very time consuming, but now with the PowerFlex drives on ethernet, all the diagnostics can be accessed in real time. The drives also have a small footprint, reducing the required panel size,” explained Mitchell.

The upgrade provided the flexibility for Arnott’s to run any biscuit on any line.

The HMI design and functionality was updated according to Arnott’s specifications to improve the way operators could load new production orders, including a feature that allows different recipes to be stored, selected and produced on the same line.

SAGE designed, programmed and installed the HMI solution allowing for a large number of recipes to be created and stored for each oven. The recipe management page enables each oven to store recipes with pre-programmed conveyor paths, line speed set points and variables. The new HMI system utilises PanelView terminals and reduces the number of pages from approximately 70 to only 20, simplifying events with each conveyor having its own pop-up with manual controls and speed settings.

With this new system, Arnott’s is able to achieve greater flexibility on each line with a reduced margin for human error. According to Andre Spoor, Engineering Manager, Arnott’s Biscuits, “SAGE upgraded our PLC and HMI with no loss in production and no downtime. It’s a great result for us considering it was such a big upgrade.”

Centralised production

By undertaking a staged approach to the control system migration, the multiple manufacturing control solutions were delivered with no unplanned interruption to production. The system was centralised with all cooling systems being monitored and controlled from a centralised ControlLogix controller.

Allen-Bradley PowerFlex drives on ethernet provide the capability for diagnostics to be accessed in real time.

Integration between the programming software, controller and I/O modules reduced development time and cost.

“The change has ensured that the site improves its ability to be flexible. It has simplified the selection and set-up process and therefore reduced operator error and provided control systems for the site’s conveyors and cooling systems that are well supported within industry,” explained Spoor.

Thanks to the upgrade, Arnott’s is well positioned to meet the growing demand for increased flexibility and agility in their manufacturing operations. By increasing connectivity across the plant floor, they are realising the benefits of smart manufacturing and are now able to build on this foundation, step by step, to work towards a connected enterprise.

Top image: Arnott’s portfolio of brands includes household names like Tim Tam, Shapes, Iced VoVo, SAO, Vita-Weat, Salada and Tiny Teddy.