If there is one innovation that is inextricably linked with the Italian filling equipment manufacturer Weightpack, it is the electronically controlled net weight rotary filler, which founder Carlo Corniani first introduced in 1979.
The principle behind it is still implemented in a wide variety of filling machines today, with Weightpack Technical Manager Paolo Marogna relying on PC-based control from Beckhoff for the company’s automation needs.
Based in Goito in the Italian province of Mantua, Weightpack has always been characterized by its innovative spirit. Indeed, this is reflected in the sheer volume of different filling lines it offers for liquid, viscous, and powder products.
Real Chimica is one of many companies that rely on these solutions. In fact, this leading brand manufacturer of detergents, fabric softeners, laundry soaps, and degreasing agents (including Chanteclair Vert) relies exclusively on Weightpack machines at its production site in Sant’Agata Bolognese.
With regard to automation technology, Paolo Marogna has been won over by the innovation potential afforded by PC-based control: “Our mission as an industry leader is to continuously improve our machines and create real benefits for our customers in the process.”
In contrast to conventional weight-based filling solutions that use a tank with constant pressure, Carlo Corniani had a novel idea for his net weight filling systems: in his patented design, he replaced the large tank containing the product to be dispensed with a distributor equipped with filling valves, which is continuously fed with the product by a positive displacement pump.
Precise and fast drive control ensures that the pressure in the distributor remains constant. This ensures that the product flow fed to the individual filling valves contains the exact quantity of product to be filled – provided that the pressure in the distributor is precisely controlled by the pump drive in real time.
Another essential consideration is that the sophisticated motion sequence of the bottle holders and other sub-functions must be controlled in sync with the filling process. This quickly adds up to over 50 axes in one machine, which calls for an advanced, flexible automation solution: PC-based control.
Paolo Marogna states, “The powerful, flexible and scalable architecture of Beckhoff technology, the high-performance products, and the comprehensive technical support are the key elements that allow us to meet our customers’ challenges in terms of innovation and efficiency.”
PC-based control technology replaces PLC
Weightpack originally adopted a more traditional approach to automating its plants, using a PLC and separate control panel. It wasn’t until 2012 that Paolo Marogna replaced the control unit with a panel PC, which also took over the initial secondary functions.
After these positive early experiences, the company began to run tests with a view to equipping the most delicate elements of the Weightpack systems with Beckhoff controllers, namely the pressure regulation for the filling distributor and the associated control of the product pump.
Today, a C6030 ultra-compact Industrial PC or a CX5130 Embedded PC, supplemented with a CP3918 multi-touch Control Panel, manages the core functions and all filling line processes depending on the system version.
This includes the weighing system, motion control for all axes in the filling station, and all other machine parts, such as the sealing machine and the ejection system for faulty packaging.
TwinCAT automation software can monitor the filling distributor in real time, and even control each individual valve and the product pump as required to modulate the product feed depending on the feedback on the pressure measured in the distributor.
This solution offers significant advantages, as it reduces the volume in the filling process to a minimum. This increases the efficiency and environmental friendliness of production, as cleaning requires less detergent, energy, and time when products are changed. It also cuts costs for materials and production downtime.
Modular plants benefit from scalable architecture
PC-based control and industrial PCs from Beckhoff provide the scalability required in terms of computing power.
“They combine the world of automation with the typical process and IT infrastructure for our machines’ production environment into one simple standard architecture,” Paolo Marogna says, stating an equally important factor for Weightpack.
Controlling all machine functions with a single controller is a huge advantage, he adds, which hugely reduces project planning and programming work while simultaneously guaranteeing optimized performance at system level.
“We see TwinCAT as a complete technological solution that not only enables automation and control applications, but also integrates them with the typical technology of the IT world − a domain that, although related to automation, remains purely IT-based,” emphasizes Paolo Marogna.
EtherCAT also plays an important role in Weightpack’s automation concept. This communication system is not only fast and robust, it also supports a wide variety of topologies and provides enough bandwidth to integrate safety and TCP/IP communication as well: “All these features make EtherCAT a versatile and universal communication platform,” explains Paolo Marogna.
The EtherCAT protocol, currently the fastest industrial Ethernet technology, offers a huge advantage in that applications can be controlled in real time without overloading the processor of the industrial PC.
This allows Weightpack to position or move applications with more than 50 axes that need to be moved synchronously with an error of less than 0.05%.
“This precision is essential to prevent bottlenecks or jamming at the high speeds at which our customers want to – and indeed can – fill and seal their products,” points out Paolo Marogna.
Crises bring communities together
For Weightpack, the COVID-19 pandemic presented a huge challenge, but also set the seal on Weightpack and Beckhoff’s close partnership.
“The demand for explosion-proof equipment for filling products containing alcohol and for corrosion-resistant machines for handling aggressive media was extremely high. Beckhoff provided us with crucial support during this difficult phase,” recalls Paolo Marogna.
During the pandemic, Beckhoff prioritized all requests from companies manufacturing equipment for medical products and hygiene articles, like Weightpack.
The large number of different components, along with the easy scalability of the TwinCAT applications, enabled Weightpack to cover the great demand for individual specific components with other solutions.
“The line of communication to sales was always open, and the technical support from the Beckhoff engineers was second to none – even in the most critical phases,” says Paolo Marogna.
Thanks to this consistency, Weightpack was able to adapt the control architecture to the available components.
“At Weightpack, we know that focusing on a structured but fully standardized solution is the best option,” says Paolo Marogna. Weightpack is thus aiming to equip all of its machines entirely with Beckhoff architecture.
Two pilot projects for integrating TwinSAFE and TwinCAT Vision have been launched recently. Another project aims to extract structured information from the mass of machine data with the help of TwinCAT Machine Learning.
Intended benefits of this approach include the ability to optimize energy consumption, minimize downtime through predictive maintenance, and suggest the best machine settings for optimal performance (Golden Batch).
“We are in no doubt that Beckhoff is the right partner for us when it comes to implementing these ideas and achieving our goal of working with high-performance machines that meet our needs,” concludes Paolo Marogna.