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By Christoph Sedivy

Industrie 4.0 is slowly but surely arriving in the melt shops. Furnaces are being equipped with more and more sensors, digital models are increasing the degree of automation, and information is being shared between different aggregates within the plant. Because the electrode control system plays a key role in electric steelmaking, it naturally assumes an important position in the melt shop’s Industrie 4.0 strategy. In addition to reliable, state-of-the-art core regulation functionality, monitoring and reporting tools and the ability to communicate with other equipment are also required. Therefore, the latest generation of our electrode control system, the Melt Expert, was developed based on Industrie 4.0 design principles. Intelligent plant condition diagnostics, performance monitoring, and user-defined reporting are essential modules in this new system. With these functionalities, electrode control systems are developing into the information and control center of the furnace. A newly developed software app brings most relevant process information to mobile devices. This feature allows steelmakers to keep an eye on the performance of their equipment anytime and anywhere. This paper describes the new features of the electrode control system and shares our customers’ operational experience. Our focus is on the practical aspects of plant status monitoring, KPI reporting, and diagnostic functionality as well as the improvements achieved.

Oct 30, 2017

By Alim Ullah

The paper discusses the necessity of upgrading low-iron containing ores, giving as an example, NML-Tata Steel Project in the Quebec-Labrador region of Canada. As cooling of pellets is generally a bottle-neck in most pelletizing plants, examples are given of the methods used to improve cooling in the existing plants and a simple, low-cost alternative, tested on a pot-grate system, is presented. The procedure described is applicable to sinter plants also. The trends in iron and steel production worldwide are then given, as well as the reasons for the increase in steel production by the Electric Arc Furnace (EAF) route. The stoichiometric and thermodynamic requirements for producing iron, irrespective of the process, are explained. The different ironmaking processes, especially the Direct Reduction (DR) ones are briefly discussed, outlining recent improvements made to some of them. The pros and cons of producing cooled DRI and Hot-Briquetted Iron (HBI) are given with predictions made for their future growth. An alternative to cold-briquetting of DRI fines is also discussed. Highlights of an ironmaking processes which is at the laboratory/pilot plant stage are given.

Aug 1, 2018

By Ernesto Furtado de Mello Neto, Eliezer Thuler, Claudio Vano Nunes, Carlos Alberto Cristofari

The Brazilian steel industry is dealing an adverse scenario with direct competition from global emerging markets. In this scenario, the need to improve asset operational performance, makes complex studies involving technical knowledge and asset life behavior, become important tools to support companies strategic accomplish. These studies allow consider performance, costs and operational risks relationship in the decision make process. The Asset Management approach support these studies in order to observe the whole asset life cycle, understand value chain through all company process and optimize the asset economic life. In this context, the present technical work has the purpose to support asset management decision making regarding ArcelorMittal Vega cold rolling drive motors, through the motors fail behavior modelling and estimated the risks involved in asset management decision. Through the Reliability, Availability and Mantenability (RAM) analysis, simulations were performed considering the failure, repair cost data and investments to build options to mitigate the operational risks.

Oct 9, 2019

By Ismar Antônio Sardinha

Usually outer straight steel tubes are used to blow supersonic oxygen into LD converters (BOF) to make liquid steel, although conical tubes are used too. Inner tube for oxygen blow and intermediary tube for water IN and water OUT are normally straight steel tubes. Present paper shows the influence of outer tube shape and metal used to in lance cooling and, consequently, a skull retention on lance surface. There are two parameters more important related to lance cooling: velocity of water out and the total lance cooling by addition of thermal conductivity of outer tube metal to it. For this comparison outer tubes are made of carbon steel or copper, and can be straight or conical. As related to velocity of water OUT, outer straight tubes have bigger efficiency than conical tubes. As related to total lance cooling, outer tube metal made of copper has much bigger efficiency than steel because of its thermal conductivity 7 to 12 times more depending on work temperature. The lance cooling has much bigger efficiency for the patented SKULLS3® technology with no skulls on the lance and no skulls into the mouth of LD converters (BOF).

Aug 17, 2017

By Karl Berger

Today we are talking about Industry 4.0, as the latest revolution of industrial processes and progress, considering that the steam engine (Industry 1.0), railways and cars, mass production in the 1920th (2.0), Industrial Automation (3.0), and finally integrated manufacturing, integrated communication, and internet (4.0) can be seen as the state-of-the-art situation in industry, nowadays. Similar to the Industry progress, we can approach the rolling process of material, which started about 150 years ago in a very basic way. Steam engine- and belt driven-mills were very operators’ intensive, brutal and risky to operate. Mechanical improvements brought throughput, safety and quantity, as also quality of the products. The rolling of steel, in particular of rails, beams, rebar, strip (focus in this paper) and plate has enabled the large scale transport and travel, the building of bridges and buildings, the manufacturing of ships and cars. From single stands to continuous rolling trains the production and quality of mills increased significantly. From ingots and blooms to slabs, we have to admit a big jump in which has changed the face of the world significantly. Thin Slab Rolling has revolutionized the output and the throughput of rolling mills (Generation 3.0 to 5.0). Finally, Endless Rolling, has boosted the quality and quantity of rolling mill processes and permitted nowadays to enter in market niches which were not thinkable a decade ago. Mastering the automation and applying reliable systems (mechanical and electronically) of drives, actuators and sensors, as also communication and information interchange to all levels of automation are the success factors of such complex mills, we call herein after “Rolling Mills of Generation 6.0”.

Aug 16, 2017

By Pedro Augusto David Machado

The hot metal produced in small blast furnaces runs with a highly heterogeneous charcoal. The result is a significantly higher hot metal chemical composition variation, especially for the silicon content, which varies from 0.4 to 1.5% in Mini Blast Furnaces - MBFs, designed to feed an EAF and/or a BOF. These MBFs operate with frequent variation in their productivities to feed preferably only one of the steelmaking reactors, that is, EAF or BOF. The hot metal suitable amount, chemical composition and temperature, to be delivered at the steelmaking vessel, become the major concerns in the integrated operation MBF to EAF or BOF. In order to cope with those undesirable frequent variations, a solution has been proposed based on the existing technologies of oxygen jets and ladle refining techniques adapted to a hot metal ladle or to a Torpedo Car. The proposed technique is not only able to adjust hot metal temperature and chemical composition, but it also generates the adequate conditions for refinement from P and S, as well as “cleaning” hot metal ladles and Torpedo Cars by melting pig iron skulls. Therefore, this new technique development results in high hot metal yield, an adequate chemical composition and bigger campaign of hot metal ladle.

Aug 17, 2017

By Jim Belous

Fluid Dynamic Modeling (FDM) was used to develop solutions how to eliminate the fugitive emissions from the meltshop building and to comply with the EPA “6% opacity from the furnace operations” rule. Secondary Emission Control (SEC) system performance was simulated by an inverted 1:96 scale Plexiglas model of the entire meltshop, utilizing the negative buoyancy effects of saline solution in water. Test results show that with the installation of the internal partition wall which separates furnace aisle from the caster aisle, significant improvement of the SEC system is achievable, thereby avoiding large expenditure for the expanding a fume collection system capacity.

Aug 17, 2017

By Wolfgang Linden

The emerging demands on higher steel grades call for improvements in the operation of production units and a corresponding increase in automated processes, and therefore international steel producers require viable functions. The avoidance of slag carry-over to secondary metallurgy processes is essential for achieving steel grade qualities and reducing alloys in order to compensate slag residues in the downstream unit. The automatic tapping procedure in BOF converters will be supported by the implementation of reliable measurements used in high-end steel plants. Automatic tapping will help to achieve the following: Reduced slag carry-over, improved yield, increased reproducibility, improved working environment and safety and operation with minimum possible crew. The automatic tapping procedure is capable of being implemented in new or retrofitted installations.

Aug 17, 2017

By Jan Lückhoff

The introduction of the EAF Quantum furnace by Primetals Technologies represents an important milestone in the field of electric steelmaking during the last 15 years. In this process the latent and chemical heat of the off-gas generated during a melting process in an EAF is used to pre-heat scrap in an integrated shaft prior the melting of the scrap in the vessel. Combining proven own technologies, Primetals EAF Quantum enables nearly continuous process, cutting down idle times and enhancing availability for production. The essential benefits will be shown in this Paper.

Aug 16, 2017

By Yuechang Wang

A new method of manufacturing the wavy-tilt-dam(WTD) mechanical seal has been mentioned. In this method, the special equipment is designed to provide a predetermined force to external and inner circular surface of the ring. After milling the end face of the seal by grinding miller and releasing the preload, the wavy-tilt-dam can be done on the seal surface. In this paper, a prediction model is built up to investigate the relationship between the predetermined force and the deformation on the surface of the ring by using ANSYS software. A WTD ring is manufactured by this method which approves that the prediction model is in accord with the real process and this manufacturing method of the WTD mechanical seal is a proper choice.

Jul 31, 2018

By Nishit Patel

Development work on the use of plasma torches in blast furnace ironmaking was completed in the 1980s. The technology developers planned to reduce blast furnace coke consumption using electrical energy and large scale coal injection through the tuyeres. Since this time, Westinghouse Plasma Corporation has improved torch reliability with industrial experience in solid-waste-to-energy facilities, as well as metallurgical applications. As coke makes up one-third of the hot metal cost, savings efforts frequently seek to lower coke consumption by increasing process efficiency or replacing coke with cheaper fuels. Alter NRG and Hatch assessed the merits of using plasma torch technology to superheat the hot blast. Coke rate savings, electrical purchase requirements, and a financial analysis to implement the torches are presented.

Aug 17, 2017

By Osmar de Sousa Santos

NiTi shape memory alloys (SMA) have been widely used as construction materials due to their shape memory and superelastic properties. Usually the application of the NiTi alloy is in the wire form, which is ideal shape to make springs, orthodontic arc-wire and endodontic files. Since our research group (ITASMART) started producing NiTi wires, it was noticed that NiTi SMA produced by Vacuum Induction Melting (VIM) presents carbon contamination, which is due to the melting process. Therefore, alloys rich in carbon remove titanium from matrix, forming precipitates of TiC (titanium carbide). Also, Ti2Ni precipitation removes titanium from the matrix and these two precipitates TiC and Ti2Ni can produce internal volumetric defect in the wire drawing process. Seeing the importance of NiTi wires as base of many applications, this work studies the formation of volumetric defects caused by precipitates in the wire drawing process of a NiTi wire drawn down to 0,39 mm in diameter.

Aug 8, 2018

By Gabriel Andrade Medeiros, Christian Brugger, Paul Pennerstorfer, Daniel Fuchshuber, Reinhold Leitnerl

State-of-the-art automation technology enables digitalization of the continuous casting process that goes far beyond conventional automation of industrial production. Primetals Technologies provides a digital twin that combines an intelligent digital representation of a casting machine as well as the casting process and the slabs, blooms or billets that are produced. It allows metallurgists and process engineers to predict the behavior of the involved complex production process and optimize parameters before using them in real production. New steel grades or production processes can be evaluated off-line without any risks to process stability and product quality. Primetals Technologies installs the digital twin with every new installation of a continuous caster optimization system. This paper describes how the setup and simulation possibilities of the digital twin provide numerous benefits by modelling and simulating the casting process. It allows for example the calculation of material properties according to the actual composition, strand surface temperature profiles and dynamic soft reduction before the final point of solidification. An outstanding feature of the digital twin is the replay functionality provided for various models to analyze and further optimize real production situations. The paper also gives an example how usage of the digital twin optimized production at a customer.

Oct 1, 2019

By Thierno FALL

This paper describes the study of the work-roll during the hot rolling process thanks to a 3D model built with the Finite Element Method (FEM). In terms of computational cost, that method needs high resources compared to 1D model which are mostly used. However, the 3D model is built to have a better understanding of the work-roll thermal and mechanical behavior during the hot rolling process. The thermal model shows that the highest temperature reached during rolling are within the range of 500°C and 600°C. The thermal field input used to simulate the mechanical behavior of the work-roll shows a biaxial thermal stress state, in the circumferential and axial planes. However, a peak of radial stress is observed in the backup zone. It did not generate plastic strain but could influence the fatigue behavior of the work-roll.

Oct 1, 2019

By Rodrigo Fina Ferreira

This paper presents a mineral liberation study on two iron ore samples from the Quadrilátero Ferrífero, in Brazil: compact itabirite of low-grade metamorphism (CI) and friable itabirite of high-grade metamorphism (FI). The quartz liberation spectrum for both samples have been obtained through QEMSCAN analyses, carried out for several comminution degrees, to compare the liberation characteristics and to evaluate the evolution of the quartz’s liberation degree after fragmentation. The results have shown significant differences in liberation spectrum between the itabirite samples studied. The liberation process of FI was easier than of CI, due its high porosity and larger crystal size compared with CI, which has shown more complex mineral assemblages with low porosity and smaller crystals. The quartz liberation spectrum has shown that grinding at P95 of 0.210 mm for the FI sample, and of 0.045 mm for CI sample, should result in satisfactory liberation for subsequent concentration step.

Aug 1, 2018

By Uazir Bezerra de Oliveira, Günther Staudinger, Michael Skorianz, Edo Engel

Oct 1, 2019

By Yasser Ghobara

Phosphorus is a problematic impurity that has challenged steelmakers for decades. Steel producers have developed specific technologies to eliminate phosphorus prior to and during steelmaking. These process technologies reduce phosphorus to various degrees and increase the cost of making steel. The state-of-the art dephosphorization technologies are described and operating costs compared for each of the established technologies. Costs are discussed in terms of price penalties for high P iron ore and selling premiums for low P steel. From this, strategies to control P in a cost effective manner are described.

Aug 17, 2017

By Dustin Vickress

The premature failure of copper staves in the lower stack and bosh is frequently the cause for an interim blast furnace repair at great cost to the blast furnace owner. Protective accretions may form on the stave hot face, but when these accretions are lost the staves can begin to deteriorate both due to abrasive wear from exposure to the descending burden materials and due to thermal cracking from exposure to hightemperature process excursions. These mechanisms can lead to failure of cooling passages, which forces blast furnace operators to shut off these channels, accelerating the rate of copper stave wear. Finger cooler technology was developed to extend blast furnace life by restoring cooling to damaged staves. Evidence for their effectiveness is presented herein in the form of experimental test work and conjugate heat transfer (CHT) analysis carried out using computational fluid dynamics (CFD) simulations. These tests demonstrate that under typical blast furnace excursion conditions, a stave fitted with finger coolers will undergo half the temperature rise of a stave fitted with conventional cigar coolers.

Aug 17, 2017

By Afshin Sadri

One of the main reasons for blast furnace reline is the loss of refractory lining, particularly in the hearth and taphole regions. Intense operation of the blast furnace can result in extensive refractory wear and deterioration. This can then affect the continuity of the operation and the furnace campaign life. Novo-Lipetsk (NLMK) and Hatch developed a systematic approach to monitor the condition of blast furnace hearth linings using Acousto Ultrasonic-Echo (AU-E), a non-destructive testing system developed by Hatch. Continuous and periodic inspections of blast furnaces revealed areas with accelerated refractory deterioration, formation of elephant foot, extent and speed of refractory wear, as well as cracks and other anomalies. Improvement in coke quality, stave washing, the addition of titania, and other changes were recommended and implemented to prolong furnace life while maintaining the intensity of furnace operation. This paper demonstrates how the coordinated efforts between NLMK and Hatch resulted in prolonging the blast furnace campaign life.

Aug 17, 2017

By Renata Cristina Teixeira

The lubricant oil is a complex mixture of different basestocks and additives. Engine oils evolved from the use of pure mineral basestocks back in the early years of automotive industry to the advent of synthetic, fully formulated, low ash lubricants. This evolution was driven by a number of factors, such as new engine designs, extended durability needs, increased fuel economy needs, environmental concerns, feedstock prices and availability and legal issues. This paper uses technology prospecting on literature and patents databases to allow an investigation on the historical evolution of engine oils. Main basestocks (mineral, hydrotreated, polyalphaolefins, esters) and additives (antioxidants, antiwear, friction modifiers, detergents and dispersants) are characterized according to their research effort. Technology prospecting data is crosschecked against the evolution of engine oil classes, allowing an analysis of how the main drivers push the development of lubricant oil quality. A research effort was identified in late 1990’s until mid-2000’s and related to the adoption of chemical limits for lubricants. Different patterns for the articles and patents publication account for the high value technological knowledge has in this industry. Technology prospecting is seen as a useful methodology for the understanding and forecast of lubricant technology movements.

Jul 31, 2018