METALSAN MAGAZINE – SEPTEMBER 2022 ISSUE
OUR ARTICLE ON “RFID SOLUTIONS IN STEEL PRODUCTION”
RFID (Radio Frequency Identification), one of the fastest-developing identification technologies, has been adapted to many sectors such as automotive, aviation, oil and gas, construction, and the iron and steel industry. Compared to traditional barcodes, it offers various advantages. It can read multiple items simultaneously without requiring direct line of sight, provides enhanced security, labels can be encoded multiple times, and data can be monitored in real time throughout the entire process.
RFID in the Iron and Steel Industry
In the current system, low-cost barcodes are used to read information. However, barcodes have limitations such as dependence on reading direction, sensitivity to environmental conditions, and vulnerability to damage. While the initial cost is low, many intangible costs arise during use. Reading rates are affected by several factors, including environmental conditions and processing. When the terminal cannot read the information, it takes time for the operator to locate the product. Trucks accumulate at logistics control points, and production line capacity decreases. Manual practices in the steel industry also carry safety risks. Crane timing relies on manual assessment and voice intercom communication, which not only increases labor costs but also creates safety hazards.
Regardless of the company or industry, RFID significantly improves the efficiency of logistics and inventory management. With smart planning and comprehensive testing, integrating RFID becomes one of the simplest ways to increase productivity and cost savings. With the right solution partner to guide the RFID process, steel manufacturers can revolutionize the way they operate. Implementing an RFID-based system in the steel manufacturing industry increases productivity and reduces costs.
Alongside the benefits, the challenges must also be addressed. Environmental conditions are harsh, products are made of metal, and factory temperatures are high. Therefore, RFID has some technical limitations; however, developments in RFID technology are providing solutions to these challenges.
Environmental Conditions
The key issue is that RFID chips and labels must withstand tough environments. Steel production is a complex process that uses extremely high heat. Steel plates retain heat for some time after production. Plates must be identified and labeled while they are still hot, and labels must adhere to hot metal surfaces. Labels must also be resistant to chemicals such as strong acids, alkaline solutions, and wetting agents.
Recent advancements in RFID technology now allow RFID chips to be applied to almost any type of label. Adhesive and non-adhesive labels resistant to high temperatures, acids, and oils can be produced.
Reflection on Metal Surfaces
Another challenge is that signals emitted by the chips may reflect off metal surfaces. Reflection reduces the reading capability of terminals. To prevent this, RFID labels must be positioned at a suitable angle and placed as externally as possible on metal plates and coils, followed by testing.
Do Metal Surfaces Interfere with RFID?
Another issue is the potential for metal to detune RFID antennas when in contact with the chip. To prevent direct metal contact and detuning, chips with absorbing materials are used. In addition, special antenna designs are employed to achieve longer reading distances.
Before transitioning to RFID, careful evaluation and testing of the above points will improve the overall quality of the implementation.
Sample RFID Applications
ThyssenKrupp, a steel producer based in Germany, implemented an RFID system. The initial goal was to save time and reduce labor. Manual identification of plates by workers was slowing down operations. Since the plates were stored outdoors, rain, ice, snow, and sunlight made barcode labels difficult to read.
Therefore, they produced UHF (Ultra High Frequency) smart labels and attached them to the plates. Readers were mounted on cranes to scan plates during unloading. Initially, the system was tested by tagging 1,000 plates at a plant in Brazil and transporting them to Germany. When the application significantly reduced unloading times and generated savings, it was rolled out to the entire Brazil facility. They even introduced an RFID-based “borrowing box” to track the use of tools and equipment.
In another steel plant, the system went a step further and Industry 4.0 was implemented using RFID and IIoT together.
In this example facility, Industry 4.0 was applied across all stages, including melting, ladle tracking, casting, and rolling, using IIoT, RFID sensors, the internet, cloud computing, big data, analytics, and machine learning.
During the melting phase, RFID sensors and IIoT devices were used to measure various parameters. In this way, heat start and end times, slag events, and contact events were identified and monitored.
The ladle tracking phase follows the journey of the heat from the furnace to casting. Assigning the steel weight, remaining weight, and tare weight to each ladle is critical for mass analysis using passive RFID tags. These passive tags were attached to the ladles with a specially designed RFID protection shield. RFID sensors in the furnace area were installed inside specially designed protective housings made from special materials.
Even within the protective shield, RFID tags may still be damaged by direct splashes, crane hook impact, and similar causes. Therefore, the shield was designed to be replaced quickly and easily in the event of damage.
During casting, RFID weighing sensors at the casting station accessed weight data via the IIoT to determine flow rates. By combining this data with the configuration of the casting station’s subcomponents, each billet was assigned a heat number. The system then determined whether a billet was transported to the rolling mill for hot rolling or to a cooling bed for later use, using RFID sensors positioned along the conveyor. For billets sent to the cooling bed, barcode label generation was defined optionally. When cooled billets were reused or externally purchased billets were processed, they passed again through the reheating furnace. Barcode labels ensured the identification of billets that underwent reheating.
Using RFID sensors, it became possible to determine whether a billet came directly from the caster (hot rolling) or from the reheating furnace.
In the rolling stage, the mill automation system monitors the transformation of the billet into a bar. When the bar finally exits the cooling bed, the tracking software already knows which billet it originated from and therefore has genealogy data such as heat number and chemistry.
In the bundling stage, the automation application receives the bundle identification number and the list of bars included in that bundle from the bundling automation system. Based on this information, the tracking application prints a label with a QR code attached to the bundle. Technical and commercial information can be accessed by scanning this QR code. The QR code identifies the package in the field for shipment and, if necessary, allows the dealer or end user to verify the bar chemistry. A mobile application enables dealers to scan the QR code and instantly access chemistry details and other required information.
In this case study, Industry 4.0 technology implemented with RFID tags connected all production stages into a single integrated process.
In a traditional system without Industry 4.0, many people are employed to connect data and information among process areas. Data is prone to errors and delays. The tracking solution implemented in this application significantly reduced human intervention. As the process progressed, data enrichment was carried out almost in real time. The ability to respond to unforeseen events improved. Products could be traced securely down to their chemistry records. Post-mortem analysis of different product dimensions linked to a specific heat (what went wrong that must be corrected and what went right that should be repeated) could be performed easily and transparently.
As the data collected across all processes and stored in the cloud increases, the next step will be possible: big data techniques and analytics can be used. In this way, uncertainties regarding the expected final product in a new production process will be eliminated.
WHY EGEN?
Egen is a manufacturer and supplier of RFID labels. With our RFID application machine, we apply RFID chips to labels whose specifications are defined by the customer. We produce custom RFID labels that may be printed, blank, or contain variable data.
In cooperation with Avery Dennison / Smartrac, we work alongside expert solution partners who install RFID systems and provide hardware. By sharing our expertise in adhesives and face materials, we produce RFID labels with the most suitable surface, adhesive, and chip for the environmental conditions.
