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By Bruce V. Kiefer

A modernization project was undertaken by Kroman Celik Sanayii A.S. in order to improve their product quality, consistency and shape of the coil package, reduce maintenance and delays in rod mill, thereby increasing utilization and productivity. The project involved installation of a new Morgan Intelligent Pinch Roll and High Speed Laying Head, modifications to the existing controlled cooling conveyor, plus replacing the coil reforming station. The new pinch roll and laying head were to provide better control of the ring formation and consistency of the coil on the conveyor, while reducing delays on the conveyor. Changes to the controlled cooling conveyor included installation of new nozzle decks and Optimesh air distribution system along with re-arrangement of existing fans in order to improve both cooling rates and uniformity of cooling. This paper explains details and features of the newly-installed equipment technology. Resulting product and process improvements are presented, including increased tensile strength and uniformity, reduction in delays on the conveyor and reform tub, plus improvements in coil quality.

Oct 30, 2017

By Marco Antonio Meggiolaro

Notches are preferential sites for fatigue and for environmentally assisted cracking (EAC) initiation. Semi-empirical notch sensitivity factors have been used for a long time to quantify notch effects on fatigue design. Recently, this concept has been mechanically modeled using techniques which properly consider the notch tip stress gradient influence on the fatigue behavior of mechanically short cracks. This model properly calculates such values from the basic fatigue resistances of the material, its fatigue limit and crack growth threshold, considering the characteristics of the notch geometry and of the loading, without the need for any adjustable parameter. Such criteria to estimate notch sensitivity and tolerable short cracks on fatigue have been extended to EAC conditions and verified by proper tests. In its simplest version, the criterion for the maximum tolerable stress under EAC conditions uses the resistances to crack initiation and to large crack propagation and the characteristic short crack size under EAC, considering the crack size and stress intensity factor. Moreover, the tolerance to short cracks under fatigue and under EAC conditions can be unified in an extended Kitagawa-Takahashi diagram, a new and potentially very useful tool for material selection tasks.

Aug 8, 2018

By Eduardo Dominguez Trindade

Lubricant oils are subjected to reciprocating movement in the piston ring/cylinder tribocouple of automotive engines. In this kind of movement, the relative speed oscillates between zero and a maximum, and therefore the lubrication regime goes from boundary to hydrodynamic. Tribotests are widely used in laboratories to hint at the friction developed in these systems. In the present work, a SRV tribometer was used to evaluate the friction behaviour of lubricant oils under reciprocating movement up to 60 Hz. A high acquisition rate allowed the analysis of data inside each reciprocating cycle. Both a pure base oil and a fully formulated lubricant were used. Changes in the contact pressure, viscosity and speed were seen to influence friction, which was correlated to the relative thickness predicted by Hamrock-Dowson equation. While some observed characteristics were typical consequences of the Stribeck curve, other effects were also observed, such as the occurrence of seizure at high reciprocating frequency. A lower boundary coefficient of friction due to additive package in the formulated oil was also observed. The results allow a better understanding of friction in reciprocating cycles and can be used to evaluate the performance of oils and surfaces in laboratory prior to engine testing.

Jul 31, 2018

By Jean François Stumper

This paper presents the TMT “3D TopScan” profilemeter, which is a Radar-based profilemeter that measures the total burden surface within a few seconds and on a continuous basis. This equipment is based on an electronically steered solid-state radar scanner, such that a very large amount of surface data is collected within short time intervals. These new electronically steered antenna systems are the key to meet the demands for both accuracy and speed. The TMT probe is installed at a fixed location at the top cone, such that it does not interfere with the charging, enabling a continuous measurement and a compact design.Blast furnace charging optimization can be achieved based on its measurement data. The burden surface is continuously measured every few seconds, enabling the blast furnace operator to detect any details including asymmetries or irregularities in the surface pattern. A variety of process analysis tools are available. Due to the continuous and fast measurement, the burden descent speed can be supervised without process interruption on an ongoing basis. More accurate process models (layer models) than ever are obtained which fully consider the unsymmetries.This technology, developed by TMT Tapping Measuring Technology, is successfully in operation at Salzgitter Flachstahl GmbH at their blast furnace B. The probe and the data evaluation tools combine today’s technological capabilities in measurement technology with the practical requirements of blast furnace operation.

Aug 16, 2017

By Pedro Jorge Walburga Keglevich de Buzin

The steel production in mini mills generates several process residues, among them there is the electric arc furnace dust (EAFD). This residue has as main elements Fe, O, and Zn, being classified as hazardous by the presence of Pb and Cd. Thermodynamic studies related to the formation of mineral species containing Fe, O and Zn elements were carried on due to the influence of these compounds in hydrometallurgical EAFD recycling processes. In recent years, a rise in the chlorine content of this residue was observed, mainly motivated by the increased use of scrap with polymeric impurities containing this element. In this work, based on computational thermodynamics tool FactSage, a general overview of gaseous and minerals species (found in EAFD) formed by Fe, Zn, O, Cl, H and C is shown – representing the organic origin of chlorine. For this study, the PVC polymer was used as the chlorine carrier substance which contaminates the EAF load.

Jul 30, 2018

By Helênio Resende Silva Júnior

Arcelor Mittal Asturias coking plant at Gijon works, Spain, is undergoing a complete modernization of the whole coke making complex. In this context, Gijon has to be considered a brownfield project, where Paul Wurth has been awarded with the engineering, supply of key equipment as well as erection and commissioning supervision services for the rebuild of two coke oven batteries the modernization of the adjacent by-product and relevant waste water treatment plants. Main objective of this paper is to present the technological improvements introduced by Paul Wurth in the rebuild of a modern plant focusing on fulfilling all the recent environmental regulations.

Oct 30, 2017

By Guilherme Guidugli

The hot blast stoves are a regenerative heat exchange system, accounting for 10 to 20% of the total energy requirement in an integrated steel plant, responsible for the supply of about one-third of the blast furnace heat input and responsible for a constant flow of hot air to the blast furnace, according to the required production. Because of their important role in the hot metal production, a stable operation and an appropriate combustion control is necessary. This paper aims to present the results of an investigation and modifications performed as an operating multi-furnace plant, as well as the parameters considered to ensure thermal equilibrium, improving in the stoves heating cycle.

Aug 16, 2017

By Armando Vazquez

Steel Dynamics Inc. (SDI) and Tenova Goodfellow Inc. (TGI) have successfully commissioned the first hybrid extractive/laser system for continuous and full spectrum analysis (CO, CO2, O2, H2 and H2O vapor) on two twin shell furnaces at Butler, Indiana. NextGen® technology using off-gas analysis as a main tool for EAF practice optimization is a proven effective method for improving plant productivity. Significant benefits attributed to the NextGen® system are operational cost reductions through the use of real-time dynamic control of chemical energy and improved environmental conditions through reduced GHG emissions. Additionally, the implementation of Tenova’s Water Leak Detection Technology® has shown results as an effective tool for operators to identify in real-time the presence of water during both reducing and oxidizing conditions. This paper will include project details, trials and results and will also outline the latest hardware developments and multipoint capabilities

Oct 30, 2017

By Luis Acainas Caballero, Karl Hoen, Stephan Krämer, Christoph Klein

The situation of the steel industry is still challenging. Worldwide overcapacities have an impact on profitability. More than ever, the point at SMS group is to provide the steel industry with flexible and profitable technologies and systems over the whole process chain. One example for that is the thin slab casting and rolling technology and, in particular the CSP® technology (Compact Strip Production), being well established for hot coil production. From its introduction in 1989, CSP® technology has been continuously further developed. Today, on a CSP® plant, the full range of high-quality steel grades can be produced with tightest geometrical and metallurgical tolerances under optimal economic conditions. With the introduction of semi-endless rolling and, as a further step, the endless rolling process, the product range for thin and ultra-thin products has been further enlarged, allowing for the production of hot rolled coils with a thickness of 0.8 mm for low carbon steel grades. Also high-strength steel grades may be produced with gauges below the minimum product thickness that can be achieved in a conventional-type hot rolling mill. Another step in the further development of CSP® technology is digitalization. In December 2016, the CSP® plant of Big River Steel (BRS), located in Arkansas, USA was put into operation. It is the first learning steel mill in the world. The CSP® plant of BRS comes with innovative technologies, providing impressive operational results right from the beginning.

Oct 1, 2019

By Jean-François Stumper, Mario Moser, Mark Kruessmann, Volker Langer, Daniel Bastos Martins Cruz, Claude Meisch

The latest generation of probes and casthouse machines provide a wealth of data that has not been available a few years ago. The evaluation of this data gives direct feedback to improve the blast furnace efficiency, the equipment maintenance and design and it allows the early detection of critical or deviating process situations. A stable operation with lower operation and maintenance costs are the final customer benefits.

Oct 1, 2019

By Tobias Krull

The characterisation of iron ore from a materials handling point of view is paramount in order to provide the best possible design for the desired application and maximise equipment uptime at the lowest possible capital and operational expenditure. Problematic issues in materials handling applications often arise in the iron ore industry due to the high density of the ore as well as the abrasive nature of the product. One of the key issues encountered during the handling of iron ore is excessive wear due to either impact or sliding abrasion. The applications and equipment typically affected by accelerated wear issues are mass flow hoppers, transfer chutes and conveyor belts. These wear issues often result in unplanned down times and loss in production which can lead to a considerable loss in revenue. This paper provides an overview of the best practises in the materials handling characterisation of iron ore and discusses available techniques for the modelling of iron ore in applications where accelerated wear is experienced. The application is illustrated through a number of industry relevant case studies for which engineering design work was undertaken to successfully reduce the wear rates of different materials handling equipment.

Aug 1, 2018

By Manfred Hackl, Sergey Bragin, Alois Seilinger

The demand for hot rolled strip is growing in multiple ways. To remain competitive, new and existing mills must meet arisen challenges in the best possible way. The production of hot strip is a key element of steel production. Since close to half of all steel produced is hot-rolled to strip, mills require maximum throughput and availability combined with geometrical precision and the ability to create optimum material properties. Today there is a clear trend in developing new steel grades with high-strength and improved formability, like 3rd generation AHSS (Advanced High Strength Steels), as well as a trend to produce thinner and wider gauges. This trend challenges hot strip mills because it requires new technologies which provide more flexibility in metallurgical treatment during the rolling process. In order to meet and promote these trends Primetals Technologies is currently working on different concepts and solutions. One example is the development of a new mill stand technology Flex-HI HOT which allows to adapt the last finishing mill stands by efficiently switching from 4-high to a 6-high mode with small work roll diameter based on production needs. Another solution is to apply a permanent 6-high rolling stand at the end of the finishing train. A smaller work roll diameter allows to achieve higher specific thickness reductions and deformation rates resulting in significant thinner hot-strip gauges with valuable metallurgical benefits. The developed solution concepts with technological and metallurgical benefits will be presented in this paper.

Oct 1, 2019

By Alexander Fleischanderl

Steel market has become somehow unpredictable and requires quick adjustment in production conditions to survive in the harsh market environment. Steel production is not anymore driven by output records, but by efficient cost reduction measures to remain competitive under strongly varying production conditions. Energy efficient production and flexible raw material scenarios have become decisive factors to succeed and survive in our industry. Such scenarios have to be carefully investigated to be well prepared to adopt production steps continuously. The paper analyses various process opportunities to optimize energy and raw material consumption in the production route. Off-gas treatment systems have still a huge untapped potential to recover energy from the hot waste gases. This is valid for the EAF mini mills as well as for the integrated route. Various examples for waste heat recovery systems including resulting benefits are discussed for the EAF, agglomeration, blast furnace, direct reduction and BOF. New innovative bag-filter systems feature extremely low emission levels at lowest pressure loss and sound emission conditions. Also improved control and automation solutions support the operators to minimize the operation and maintenance costs of their off-gas system. Steelmaking by-products shall not be considered as residues, but as a valuable and cheap raw material source. The paper presents some show cases how to valorize slags as well as utilizing coke and iron oxide fines to increase productivity and minimize raw material cost. A new process for highly flexible converter steelmaking allowing for extraordinary high HBI and scrap rates above 50% and improved yield is discussed and evaluated

Oct 30, 2017

By Andrea Taurino

Innovation means implementing a new product or a product that has undergone significant improvement over time, in terms of method, form and performance. Innovation encompasses all the scientific, technological, organizational, financial and commercial steps that need to be taken to put it into operation. Innovation combined with research and development makes it possible to perfect the product with consistency over time. Taking inspiration from the bases developed by the Austrian economist Joseph A. Schumpeter back in 1911, Danieli came up with the concept of “Innovaction” – a combination of Innovation and Action, to refer to the development and advancement of various products for the steelmaking industry, including the loop laying head for wire rod.

Aug 17, 2017

By Marcus Weldon

We are at the beginning of an era of profound transformation and human progress — a new industrial revolution. This “Automation of Everything” era will be brought about by digital interfaces, data analysis and control of the physical world through networks employing the Nokia Bell Labs Future X1 architecture — networks to support the digitization and connection of everything and everyone with the goal of automating much of life. The interconnection of robots, machines, drones, sensors, processing platforms and people through Future X networks will provide transformative tools for the automation and optimization of factories and warehouses, ports, electric grids, transportation networks, food, healthcare, construction, logistics and supply chain, emergency response, mining, and other physical industries. To date, the level of automation has been modest at best. Automating these physical industries — industries that account for 70 percent of the US Gross Domestic Product, for example — has the potential to drive significant increases in the world’s economic productivity.2 Realizing the potential of this next industrial revolution will require billions of wirelessly connected endpoints for high fidelity physical-to-digital conversion, millisecond response times to tightly control and coordinate machines and robots, and intelligent analysis to optimize real-time decisions — tasks beyond the reach of current networks. Increased levels of automation are already being achieved through the use of 4G advanced wireless access technologies. The untethering of sensors and actuators in industrial environments through the low-latency, high-bandwidth, high-reliability, and massive scale provided by 5G wireless access will complete this evolution, providing an unprecedented ability to digitize, analyze, comprehend and manipulate the physical world at a scale never previously thought possible. These new capabilities will enable us to create digital models of the physical world with ever higher levels of fidelity, further enhancing our ability to improve operational efficiencies and increase productivity and worker safety. Doing this will require a dramatic evolution in network architecture toward massively distributed cloud control and baseband capacity to achieve the required ultra-low latency and ultra-high bandwidth for industrial and infrastructure automation services — the Future X architecture. In early 2019, Nokia Bell Labs will publish a sequel to “The Future X Network: A Bell Labs Perspective”. “Future X for Industries: A Nokia Bell Labs Perspective” will explore how the Future X architecture will automate many of the world’s physical industries, including chapters devoted to electric power, cities, rail, mining, public safety, manufacturing, ports, logistics and supply chain, and an overarching chapter devoted to securing this highly automated world. To give you a small taste of the feast that’s to come, we’re sharing with you an initial installment — “Future X for Industries: Mining” — the Nokia Bell Labs view of how mining will be transformed through a Future X architecture..

Oct 1, 2019

By Wolfgang Linden

One of the most important factors in successful electric steelmaking is the continuous observation of the process and the reaction to it. Traditional electric arc furnace control uses mainly direct controls which are based on the electric power input. Not considering the furnace conditions will necessarily lead to suboptimal operation in terms of energy consumption and productivity not fully utilized.The ARCCESS FEOS (Furnace Energy Optimization System) includes the simultaneous control of the transformer tap, impedance operating point, reactor tap, burner and carbon injection, and DRI charging control. FEOS has proven in practical operation benefits of high melting yields, no interruptions through switch offs in borderline temperature area, rapid reaction, reproducible and efficient electrical energy input and short power-on times.

Jul 30, 2018

By Xihuai Gong, Hongshuang Di, Jianping Li, Ning Yan

In this work, we investigated the effect of the rolling process (warm-rolled or cold-rolled) on microstructure evolution and mechanical properties of 9Mn steel. After intercritical annealing at 670°C for 10min, both cold-rolled and warm-rolled microstructures are composed of ultra-fined austenite and intercritical ferrite. The austenite in warm-rolled sample includes two types of morphology, namely equiaxed and lamellar, which exhibits a wide distribution of grain-size. The incomplete recrystallization or recovery behavior of ferrite in warm-rolled and annealed sample results in higher yield strength and shorter yield point elongation. Moreover, the warm-rolled and annealed sample extends the TRIP-related work hardening over a broad strain range, resulting in a better combination of ultimate tensile strength and total elongation.

Oct 1, 2019

By Gustavo Borges Tiboni

The erosive wear caused by the impact of solid particles against a surface is a tribological phenomenon present in many segments of the industry, such as transportation, aerospace, mining, power generation, among others. The most usual method to set the wear rate is by measuring the mass loss of the material. In order to apply one technique with potential to determine the rate of erosion wear, this study developed a dedicated equipment and conducted preliminary erosion tests monitored by non-destructive testing known as acoustic emission technique (AE). This can be defined as a technique able to detect mechanical waves generated by the release of elastic energy accumulated in the material. Erosion tests were performed in order to evaluate the ability of equipment to collect data from AE and to correlate these data with the wear of the samples. Samples of low carbon steel eroded by the impact of angular aluminum oxide particles suspended in air at three different velocities: 45, 57 and 67 m/s. The impact angle between the particles and the sample was set at 30 degrees and the test temperature at approximately 20°C. The wear rate has changed with the velocity in accordance with the kinetic energy of the particles and the AE parameter RMS showed sensitivity to the variation of particle impact velocity and to the wear of the sample eroded. The rate of AE signals collected over time correlated with the flow of particles striking the sample, and with the parameters of energy, rise time and duration of the signal.

Jul 31, 2018

By Paulo Masiero

Sintered titanium carbide has been extensively used since the early 1980s for demanding wear-resistant applications and, in particular, in environments characterized by high temperature and oxidation. Thanks to its physical characteristics, especially its low density, titanium carbide (TiC) has been successfully applied in the manufacture of cassette guide rollers for hot steel rolling. However, the peculiar characteristics of the sintered Ti carbides make it difficult their redressing and hence this has always represented the limit for a more extensive application. Very often iron based alloys are preferred even if, in general, they are less cost effective just because they are easier to be redressed by turning. The availability of a simple, compact, fully automatic and reasonably priced CNC machine; specialized in the grinding of guide rollers and able to operate accurately and efficiently -both in contour and in plunge- can definitively solve TiC’s redressing problems and render its use even more widespread and attractive.

Oct 30, 2017

By Edgar Ivan Castro Cedeño

En la producción de aceros limpios el control inclusionario es crítico para la obtención de un producto que cumpla con los requerimientos de calidad. El análisis de la distribución de tamaño de inclusión mediante modelos estadísticos permite estimar la incidencia de inclusiones en el producto solidificado a partir de mediciones tomadas en muestras relativamente pequeñas. En seis coladas de acero bajo carbono desoxidado con aluminio se tomaron muestras de acero a lo largo del procesamiento en horno olla y colada continua. Las muestras se prepararon para estimar mediante análisis metalográfico los tamaños de inclusión. Los datos de tamaño de inclusión se analizaron mediante modelos estadísticos de valores extremos, se hace una comparativa entre la distribución Gumbel (que forma parte de la norma ASTM E-2283) y la distribución Generalizada de Valores Extremos (GEV). Mediante una prueba de hipótesis con el estadístico Anderson-Darling, análisis de cuantiles y con la función de supervivencia se demuestra que la población inclusionaria se describe de una mejor manera con la distribución GEV. Finalmente se da un estimado de la incidencia probable de inclusiones en el producto solidificado.

Aug 16, 2017