• Steel is replacing a 40-year-old hook conveyor system with modern pallet transport logistics

    Full automation in the pallet world

Renowned Swiss steel producer Swiss Steel is increasingly committed to digitalisation in the area of coil transport and is replacing its nearly 40-year-old system with modern pallet transport logistics. PSI’s existing materials tracking system has been adapted to the new requirements and has successfully brought order to the world of pallets. Part of the Schmolz & Bickenbach Group, Swiss Steel is offering a good example of the evolutionary character of Industry 4.0 in the steel industry.

 

 

In steel production, Industry 4.0 and the associated digitalisation is not an issue that is solely limited to new plants. The usual investment cycles in the industry do not allow every new technological development to be implemented immediately. So, manufacturers need to develop a clever strategy that lets them leverage the benefits of continuing digitalisation on a step-by-step basis. It is important to identify and modernise specific areas of the process chain in different stages. Swiss Steel AG have made just such an investment in Emmenbrücke, Switzerland. The special steel manufacturer manufactures products including highquality wire on two lines for different formats. This wire comes off the rolling mill in wire coils and the subsequent processing steps include cooling the hot coils, taking samples, weighing, pressing, and binding. For the past 40 years, this has been done using a hook conveyor system. Options to intervene in the material transportation were few and far between. The new pallet rail, on the other hand, has been equipped with three buffer lines, where one material can overtake another. This has several advantages, including the ability to prioritise a material or an entire customer order. Investments in the new transport system and a state-of-the-art press have resulted in significantly lower energy consumption and greater transport reliability. In future, Swiss Steel will be able to meet the increasing demand for higher coil weights and innovative customer requests. And the fully automatic handling of the pallets also means a safer working environment in the factory area.

Material tracking as the key

Even in the past, a material tracking system from PSI guaranteed seamless recording of all material movements. With the new system, however, the task of material tracking has become even more pivotal. Conversely, the increased flexibility leads to the elimination of rigid material flows. With such a “forest” of pallets, “where is my material?” becomes the crucial question. It is no longer possible for human operators to maintain an overview. The automation systems involved need to be even more closely coordinated to prevent material from being mixed up at intersections or material weights being incorrectly allocated. In practice, checkpoints have been set up where the participating systems check the synchronicity of their data. The basic automation system determines whether there is material on the pallet, while the PSI tracking system determines what material this is.

Are people still needed?

In the context of Industry 4.0, there has been a lot of speculation about the role that people will or should play in the factories of the future. At an academic level, quasi-philosophical arguments are being waged about whether a factory controlled by artificial intelligence and algorithms can ever replace or even improve the complex social structure of today. Practical examples already allow some conclusions to be drawn. Even though the case of Swiss Steel is by no means an attempt to implement an unmanned factory, the firm has invested heavily in digitalisation and advanced automation in a specific area. However, there is one factor that is more powerful than the automation systems that have been mentioned, and that is the operator. If an emergency occurs, the operator can and must make corrections if the reality diverges from the virtual pallet tracking; for example, if a wire coil is removed. If something like this happens, the operator is responsible for making corrections in all systems. In essence, he is upgraded to the position of responsible supervisor if the system deviates from the automated routine. In other words, steel production will continue to be impossible without people in the future, even if their tasks change.

Open-heart surgery

Designing this kind of system on the drawing board is one thing; introducing it alongside live operation is another. Just as surgeons plan and train in advance for open-heart surgery, this was also necessary at Swiss Steel, ultimately leading to a successfully planned, tested and prepared introduction. Timely and coherent communication between all involved parties is crucially important. Commissioning cannot be carried out without any errors whatsoever, and experience and trust are needed to deal with setbacks and problems. From a purely practical point of view, it is always one thing to work through a particular signal chain in a test environment and to certify that the system is functioning properly, and quite another to run several signal chains simultaneously during operation. This is when any remaining problems will be revealed, and the excitement about a well-functioning system quickly turns into stress. At Swiss Steel, “beaming” was briefly introduced, which means transporting a material from one point to another without any time delay. However, since this only happened virtually, it materialised as a delayed signal for the transfer of the material from the pallet rail to the hook conveyor system. This is because it involves the material moving past the transfer position, and then suddenly jumping across the system onto a hook. These and other perhaps less “innovative” phenomena could be resolved quickly during commissioning.

 

 

Interview with Dr. Georg Nussbaum

Rolling Mill Director, Swiss Steel AG

PSI: What was the main reason for this significant conversion of the plant?

Dr. Nussbaum: The almost complete overhaul of the transport system was essential because the market fundamentally requires higher coil weights. As part of the strategic expansion of the Swiss Steel AG rolling mill, this was one of the first steps needed to ensure we are able to meet this and future needs. In addition to market requirements, it was also simply a case of needing to replace an almost 40-yearold system, and to integrate it into the innovative automation platform of the rolling process.

PSI: Could the complexity be predicted and how did you prepare for it?

Dr. Nussbaum: Of course, it goes without saying that this was a major project for us and still is; as such, both we and various other trades have invested significant resources into the project. This increases complexity compared to a greenfield project, because construction and production have to be carried out simultaneously with no room for manoeuvre and with ever-tighter scheduling, and there are no backup capacities during commissioning. Not every project partner identified this at an early stage, which meant that the complexity was underestimated. In future, our approach will be to monitor progress even more closely and to ensure better management of consequences.

PSI: Is a special customer-supplier relationship required to implement a project like this?

Dr. Nussbaum: A willingness to communicate and prompt, error-free reaction between partners is an absolute must. I would regard it as a special relationship if there is a deep understanding of the customer's requirement, and the project partners always act in an entrepreneurial spirit. This is much easier if the "chemistry" between the parties is right. People simply make the difference! However, everyone who is involved must understand that a project is not an end itself. Ultimately, we too have a duty to our customer, and want to offer them added value.

Digitalisation- why?

Investments in digitalisation must offer added value, and cannot simply be made for the sake of new technology. In the case of Swiss Steel, it is not enough just to manufacture high-quality products. The material quality must also be verifiable. This means that it is important to know the location of a particular material at all times, and the process parameters which govern it. This is the only way that the quality can be guaranteed in the long term during live operation and then documented on completion. This, together with the flexibility gained in the material flow and the savings in energy consumption, clearly demonstrate the advantages of digitalisation. Industry 4.0 does not have to mean revolution; the case of Swiss Steel proves that it can also be evolution.