INEVITABLE: Optimising performance in the metal industry

The metal industry is an essential part of the European economy, supplying several downstream industries including construction, automotive production, mechanical and electrical engineering, and aerospace. The steel industry alone supports over 2.6 million jobs in Europe, which makes up more than half of the entire world’s crude steel production capacity. On average, the sector produces 160 million tonnes of steel per year at more than 500 steel production sites and is a world leader in innovation and environmental sustainability.

However, European metal producers are under pressure. Various issues in recent years have meant that the focus has been on survival rather than growth. Environmental regulation, global competition, increased prices for energy and raw materials, and recent turbulence in global supply chains due to COVID-19 and the Russian invasion of Ukraine, have all contributed to an environment in which European competitiveness has never been more critical.

The EU-funded INEVITABLE project aims to help optimise the metal industry through the digitalisation of crucial processes. Rather than directly upgrading equipment, it aims to digitalise the supporting infrastructure to improve control of the processes involved. Traditional process automation and control systems will be upgraded by applying the functionalities of digital factories and Industry 4.0 concepts.

Project coordinator Dejan Gradišar explains more about the ideas behind INEVITABLE. “As more and more factories become equipped with Internet of Things technology, we now have access to an unprecedented amount of data, from which we can extract knowledge and solutions,” he says. “To get inside the inner workings of a process, advanced data analytics is necessary. We will develop and use soft sensors, digital twins, decision support systems, and supervisory predictive control to make this happen.”

The project partners involved consist of four industrial end users, four institutions specialised in the metal industry and related control technologies, and four specialists in process automation. Together, they will develop and provide digitalisation-enabling technologies to support data collection and implement new sensor technologies and tools for data analytics and control optimisation. The developed technologies will be demonstrated, tested, and evaluated on the selected use cases, dealing with primary and secondary metallurgy, steel processing, and nonferrous alloy casting processes.

SIJ Acroni is a producer of flat rolled steel products and is one of the end-user partners in INEVITABLE. Production of steel at SIJ Acroni begins with an electric arc furnace, where the input material is melted to create crude steel. Refining processes in a LD-VOD/VD reactor are carried out to achieve the required composition of the steel. Following this, continuous casting produces steel plates, which are first rolled while still hot, and then finally rolled while cold through a machine called a Sendzimir mill (ZRM) to create the final product of steel strips.

As part of INEVITABLE, the electric arc furnace and Sendzimir mill stages have both been optimised. Gradišar explains more about how the final cold rolling process using the Sendzimir mill has been examined. “With these machines, there are many things that need to be carefully controlled in order to produce a good final product,” he says. “Our work on improving automation control will allow SIJ Acroni to produce better quality strips with lower deviations. This will be especially useful for applications such as the production of electric drive systems used for electric and hybrid vehicles, where the quality of product must be excellent.”

Also as part of INEVITABLE, SIJ Acroni carried out ZTM process retrofitting at the beginning of the project, which has already brought about improvements. The existing controls dated back to 1974, meaning that the implementation of advanced process control was limited. INEVITABLE has retrofitted the mill with new automation and control equipment, including a programmable logic controller and sensors for measuring different process parameters, and has also installed new control software.

The system has been retrofitted with new automation and control equipment, including a programmable logic controller and sensors for measuring different process parameters, and has also installed new control software. This now allows the gathering of process data, with 700 different streams of data being collected at a frequency of every two milliseconds, which is being used to improve the production process and support equipment monitoring. When steel plates arrive at the Sendzimir mill after the hot roll process, they are not always the same. Thickness is not entirely homogenous, and so INEVITABLE has created a system whereby the parameters of how the mill is set up can be set dependant on the specific characteristics of the plates being milled.

Diagnostic, condition monitoring and optimisation algorithms for ZRM have been developed as part of INEVITABLE. The tool simulates and suggests optimisation steps for improving the cold rolling technological process. Using it, SIJ Acroni can optimise the rolling recipe variables (tension, initial rolling forces), and at the same time, the tool will help to detect various anomalies. “Equipment monitoring allows the company to identify if something is going wrong before severe damage to the equipment occurs,” says Gradišar. “It also enables them to forecast the best time to carry out maintenance. Maintenance stoppages are costly, as production must entirely shut down, so planning this properly in advance can save a lot of money.”

Of course, the Sendzimir mill at SIJ Acroni is just one of the three use cases being worked on in INEVITABLE. In the second use case, smart sensors and model-based decision support systems focusing on secondary metallurgy and continuous casting process are being developed for producing ultra clean steel, while the third use case is aiming to improve investment casting by building a digital architecture and optimising the process using data models.

To help spread the findings of the project and create value for industries across Europe, eight different training materials about the technologies being worked on have been published and are freely available. On top of this, a comprehensive set of instruction have been produced to help companies build the digitalisation infrastructure needed to implement the solutions developed by INEVITABLE.

“This methodology aims to guide companies through a systematic review of their digitalisation status and identify the steps needed to implement an appropriate digital infrastructure,” says Gradišar. “Using this approach, companies can review the digital maturity of their processes, formalise their target objectives, and prepare a proof of concept for the required digital infrastructure.

“This approach goes beyond initial digital maturity assessments, supporting the definition and preparation of concrete actions that will be needed to select and integrate appropriate digital platforms.”