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By Walter Mazon, Marcello Rodrigues Cruz, Leandro Carvalhar Maciel

Filtration is the operation of liquid solid separation commonly applied in the mining industry. The use of filtering chemical agents is a technical solution viable for filtering optimization. The present work proposed to evaluate two filtering chemical agents (surfactants) to reduce the final moisture content of iron ore concentrate from Ferrous Resources. The leaf test top feed was done with the FLOTICOR FA 7241 and FLOTICOR FA 16557 products. The foaming profile of the filtrate was also evaluated, once excessive foaming is undesired when using this kind of products. The results showed a reduction in the final moisture of the filter cake. The product FLOTICOR FA 16557 achieved the best results, reducing final cake moisture from 10.4% to 9.8% at the dosagem of 25 g/t, besides presenting a fast kinetics in the foam drainage, presenting itself as a technical alternative for filtration optimization.

Oct 3, 2019

By Alessandro Martinis

The performance requirements for modern steelmaking facilities are ever more stringent, as customers and markets are continuously pushing for technologies which allow having high quality steel produced in an economic and sustainable way. In the details, this paper has the aim to present the excellent results obtained by integrated steel plant where an EAF is fed with high quality hot ENERGIRON DRI. The recent technology developments, combined with the affirmed basic process design, contributed to further maximize the energy of the DRI, reaching the EAF at temperatures above 600°C with a carbon content up to 3.5%, as confirmed by plant data. These improved input material characteristics resulted in reduced electrical energy consumption and increased liquid steel production.

Aug 16, 2017

By Washington Martins da Silva Júnior

In stamping process, sliding between metal sheet and forming tool leads to wear of tool surface. Maintenance of stamping tools involves polishing the tool edge, or, in case of severe damage, replacement of the tool. Hard coatings have been applied on the stamping tool surfaces in order to reduce the maintenance cost causing a great economic impact in metal work industry. In this work, CrAlSiN coatings were applied by PVD onto SRV2W tool steel. The coating toughness was avaliated by the critical load in scratch tests. The following coating parameters were analyzed: 1- substrate surface finishing process; 2- coating architecture (multilayer or gradient); 3- chemical composition of the coating. AlSi concentration varied from the substrate/coating interface to the surface. Coatings were 3 µm thick. Scratch tests were carried out using a Vickers indenter. The applied normal load was varied from 0 to 13 N for a scratch length of 5 mm. In order to study the effect in the toughness, the substrate roughness was controlled by the finishing process before PVD coating. Samples subjected to polishing presented highest critical loads. Gradient coatings presented higher critical loads than those with a multilayer architecture. Coatings with higher concentration of AlSi near the surface supported higher loads before failure.

Jul 31, 2018

By Geovane Viturino da Silva, Jeziel de Melo Canedo, André Wulff Hirano, Maxwell Pereira Cangani, Luiz Henrique Curado Ribeiro

With the deterioration of the quality of the iron ore, the new conditions of quality of the raw materials (mainly sinter feed) were adapted to their processes, resulting in the need for changes in the chemical quality of the sinter for blast furnaces in the Ternium Brazil, without changing the parameters of chemical, physical and metallurgical quality. Due to the change in this scenario, there was a great impact on the quality of the fine iron ore this year in 2019, due to which the work ranges of sinter MgO and B2 were currently modified to minimize these impacts in the blast furnaces of Ternium Brazil. This work aims to minimize the effects of the sinter worsening, with the reduction of the sinter MgO and B2 bands, with an increase of 2% in the mixture yield and FeT elevation in the range of 1.6% in the sinter product.

Oct 1, 2019

By Augusto César Barrios Tamayo

The high temperature erosion of Thermal Barrier Coatings (TBCs) is one of the main factors that define the lifespan in gas turbine components as it is considered the second source of failure of hot path components in power and propulsion turbine operation. The worn Top Coat (TC) surface in components such as first stage turbine blades affects the turbine efficiency due to energy losses and the increment in heat transfer to substrate. The first part of this work consists in describing a HTE test facility developed to emulate the damage conditions found in a number of components of gas turbines; in this testing machine, the samples were exposed to combustion gases moving at velocities close to 1.5 Mach and temperatures of 1100°C. The second part consists in the characterization of liners and first stage turbine blades of a GE7FA gas turbine used for power generation. The last part deal whit correlation of the features of TC’s worn surfaces with the erosion conditions and the dominant degradation mechanisms between test samples and turbine components were compared.

Jul 31, 2018

By Patrik Bloemer

Reliable and accurate furnace bath level data during the melting process is invaluable for good decision making and furnace optimization, while obtaining such information rapidly and safely on a regular basis is of paramount importance. This paper shows how a melting process problem was identified as a concern, how a solution was sought and how a real-time measurement system was tested by simple modification to an existing temperature sampling manipulator. Also how, with furnace power on or off, taking reliable hot heel, fill and running levels could be used to assist melting control, aid decision making and improve safety.

Jul 30, 2018

By Thiago Pinto Silva, Leandro Rocha Lemos, Luiz Fernando Andrade de Castro

This paper shows an evaluation about effect of dispersant sodium silicate along to limestone, in the form of pulp, on the cold agglomeration process for iron ore sintering. Before that, it was verified the effect of pH, solids content and amount of dispersant on the stability of the system (limestone, water and sodium silicate). It was found that the lower the solids content, the more alkaline pH and the amount of sodium silicate equal to 20 l for each 1t of limestone, was the level of dispersion of the system. The influence of the limestone pulp with dispersant depended on the granulometry of the ore mixture and the type of technological route. For the thinner type (42,8% <0.15mm), the limestone pulp with dispersant reduced the resistance of the adherent layer of the cold agglomerates, regardless of the technological route. However, for the coarser type (24,7% <0.15mm), the limestone pulp with dispersant increased the average size of the aggregates, preserving the resistance of the adherent layer when manufacturing with two intensive mixers in series.

Oct 1, 2019

By Delvaux Carlos de Miranda Sobrinho, Hegler Zurick Arantes Assunção, Marco Venicio Mendonça de Souza, Luciano Toledo Ribeiro

This paper aims to present the development of a 600mm U-Pile that was done in Gerdau’s Ouro Branco Heavy Section Mill in order to feed the local market with a product.The focus of this study is to show the developmental process the Mill went through until it was prepared for hot trials. All roll pass and guide designs were developed by our own team. Analytical tools like Finite Element Analysis and reduced scale lead trials will be shown and how these tools impacted on the development timeframe and accuracy of the final results on steel.

Oct 1, 2019

By Haruki Inami, Takashi Ishida, Kazuhiro Ohara, Hiroyuki Imanari

The highly competitive business environment of the international metals industry is driving demand for more cost-effective operation of steel making facilities, rolling mills, and strip processing lines. Achieving stable operation is vital if the steel industry is to produce high-quality products constantly and productively. In recent years, advances in computer processing speeds, data acquisition rates, and data storage capacity have rapidly led to greater use of the new technologies of big data, analytics, the IoT, and AI by control system designers and process engineers, and the introduction of industrial applications. The “Smart Rolling Mill” solutions for hot strip mills have been developed by our group with the goal of achieving sophisticated, state of the art, and automated operation in steel rolling mills. The various solution engines improve process stability, increase the performance of mill equipment, and provide improved process control. These solution engines are based on extensive knowledge of the rolling process and the associated control systems. Two solution engines in particular are the diagnosis systems for rolling condition and for product quality that contribute to cost-effective operation and lower yield loss. This paper focuses on the diagnosis systems for rolling condition and for product quality in hot strip mills. Advanced information technologies using big data analytics and machine learning are applied to real-time data collected from the automation system that controls operation and the rolling process. We have developed diagnosis solutions for rolling condition and product quality utilizing predictive and clustering diagnosis. Predictive diagnosis prevents serious problems by detecting changes in the state of the plant or in the rolling condition. Clustering diagnosis classifies patterns of fluctuation in product quality trend charts, providing effective tuning guidance for improving product quality. This paper describes these applications with several examples.

Oct 1, 2019

By Chengjia Shang

Aiming at greatly increasing efficiency and saving budget, higher strength and larger-diameter pipes have been developed and applied for constructing long distance pipeline projects in China. At the same time, in order to produce pipeline steel with high strength, high toughness and excellent DWTT performances, it is critical to refine austenite grain by static recrystallization rolling. Therefore, this paper focuses on the brief introduction of development of pipeline projects in China and also on the basics research in the field of static recrystallization during austenite processing of Nb-bearing steel.

Oct 1, 2019

By Moisés Paulo Teixeira

The use of tailings for the synthesis of new materials is a worldwide concern today. This paper approaches the utilization of tailings of soapstone (steatite) in order to produce ceramics. The results show that the addition of soapstone in a ratio over 20% in the ceramic mass has enhanced the bending resistance of the ceramic samples when they were fired at temperatures of 900°C or 1000°C.

Oct 30, 2017

By Álvaro Lúcio

This paper outlines the DPC process as na economic and environment friendly option for the use of cultivated forest as a source of raw material for metallurgical charcoal.The DPC process was specially developed to bring logistic, environmental, technical, economic and global energy efficiency when compared to termal1 the existing biomass carbonization process. The DPC process utilizes the volatile materials (condensable and non condensable) as a source of the energy required by the carbonization process guarantying its complete combustion. As result the DPC process avoids the burning of termal1 the loaded wood, obtaining a higher charcoal to biomass yield, and avoids the emission to the atmosphere of polluting gases. Gases emitted by the carbonizing wood have na energy termal1e enough to dry the wood soon after its harvesting. By avoiding the storage in the field during na average of 150 days, the resulting economy is quite significant. As a termal1e1 the higher charcoal to biomass yield na termal1e1e economy is obtained through the reduction of the cultivated forest term. This paper emphasizes the economic advantages of the DPC process.

Aug 16, 2017

In today’s competitive steelmaking environment, the optimization and continuous supervision of the blast furnace process is of major importance. Modern probes and process measurement systems can assess the specific operation of the blast furnace. They provide a better and detailed process understanding and control. The benefits are even more important when they are combined with process models and expert systems. Everyday operation, productivity and even the lifetime of a blast furnace can be significantly improved by collecting, interpreting and acting upon such process data correctly. Only a comprehensive knowledge of the various process phenomena together with measurement of process variables inside the blast furnace enables the operators to optimize coke and fuel rates, to run the blast furnace smooth, reliable, and safe, and to make best use of the available raw materials. While the improvement of the blast furnace process with respect to productivity remains the main task, also, the timely identification of abnormalities and the assessment of process variations is an objective. This paper describes the blast furnace measurement systems that are available for everyday automatic use and provides an understanding for the possibilities of modern probes. The different applications are daily blast furnace supervision, charging process optimization, and observation of the internal state. Finally, the paper gives recommendations on probe configurations for different blast furnaces sizes, considering both a technical and an economical point of view.

Aug 2, 2018

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 Klaus-Peter Kinzel

Staves Coolers de cobre proporcionaram uma excelente proteção da carcaça do alto-forno em áreas de alta temperatura. Isso resultou para que os operadores de alto-forno alcançassem alto desempenho em termos de produtividade e taxa de combustível, além de campanhas de mais de 15 anos. No entanto, nos últimos anos, alguns altos-fornos experimentaram um desgaste prematuro nos staves de cobre. Algumas dessas empresas se alinharam com Paul Wurth para investigar a causa fundamental desse fenômeno com base em todos os fatores de influência e, em seguida, propor ações corretivas. Estes resultados são discutidos e apresentados a seguir no trabalho técnico.

Oct 30, 2017

By Filippo Verlezza

Conventional wire rod blocks have some limitations. They can only roll with fixed reduction ratios which always require the same rolling diameters within the block. With MEERdrive® SMS, as a pioneer, has introduced an innovative drive concept for wire rod blocks that can overcome the limitations of conventional solutions. The clue: the concept is based on individual drives for each stand position. The exigent wire rod market demand and the available technology melt in a new variant of MEERdrive®, the MEERdrive®PLUS, which represents a sizing block solution for finished size rolling and allows conventional as well as thermomechanical rolling. Further “one family rolling” is also possible, since all roll / size changes will occur in this block.

Oct 30, 2017

By Esteban Ruisanchez Rodriguez

In this paper we will discuss the process of the grain size customization of the EBT filler sand in relationship to the technical characteristics of the furnace and its tap hole. By customizing the grain size distribution, the glassy area formed on the top of the tap hole varies and supports differently the metallurgical pressure of the molten steel providing increased free opening speeds. Taylor made sand improves therefore the free opening rate, reduces the tap to tap time and increases the lifespan of the tap

Aug 16, 2017

By Davidson Marcos de Oliveira, Antonio Adel dos Santos, Vicente Tadeu Buono

The benefits of using the controlled rolling process followed by accelerated cooling (TMCP), currently used in the main rolling mills in the world are already well known and metallurgically based. The need to obtain mechanical properties with a high degree of homogeneity means that in some situations the ends of the rolled material are discarded, negatively affecting the metallic yield of the process. Therefore, this work focused on the determination of the mechanical properties variation at the ends of thick plates processed by TMCP of steels for application in oil and gas pipelines, in order to map the extent of these differences and to correlate them with the microstructure obtained, the profiles of temperature and cooling rates in these regions. To perform the work, two slabs of the studied material were rolled, and the temperature profile was recorded along the plate in the controlled rolling and accelerated cooling processes. The ends of the material were sampled in sections at every 100 mm and subjected to tensile test, hardness and the Charpy V-notch impact test, as well as dilatometry and microstructure evaluations. For the used process conditions, the results indicated the formation of a banded microstructure, basically consisting of polygonal ferrite and bainite, occasionally containing small fractions of perlite. The mechanical properties in the top and the base were higher than the values found in the plate middle, justified by the microstructure found. The work allowed understanding the relationship between the mechanical properties, microstructures and process conditions at the ends, helping the team to improve the process in order to result in a high degree of homogeneity of the product and, thus, lead to optimization of the metallic yield.

Oct 1, 2019

By Jéssica Vicente Luiz, Rayander Martins Pimenta, Everton Pedroza dos Santos

The Hybrid Pelletized Sinter (HPS) is a agglomeration process that involves the combination of conventional sintering and pelletizing techniques and can be used with the purpose of obtaining improvements in the agglomeration stage of iron ore, and one of the great advantages of the process is the use of a wide particle size range of the ore. In this way, the superfines of low-cost ores, which are improper in sintering, can be used in the HPS process for the formation of the quasi-particle. The use of HPS with the sintering plants of the industries presented throughout the study, enabled an increase in productivity, decreased fuel utilization and reduced slag formation in blast furnaces. Thus, the present study aims to present a review of the literature on the Hybrid Pelletized Sinter (HPS) process and its main characteristics, as well as the results obtained by the companies that adopted the process.

Oct 1, 2019

By Willian dos Reis Lima, Breno Totti Maia, Guilherme Silva Machado, Adeilson Roberto Ribeiro, Carlos Alberto de Souza, Douglas Augusto Pena, Fabrício da Silveira Garajau, Marcelo de Souza Lima Guerra

Oct 1, 2019