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By Carlos Renato Inchoste Meure, José Ernesto Boff

Nowadays, many companies have the idea where to be occupied is to be productive, this work aims to show with practical tests that to get the best performance of the machine with tools of high performance and yield is the best option for a company to become productive and economic at the same time . The company targeted for this work began its activities in the Metallurgical branch more than 75 years, Metisa Metalúrgica Timboense serves the national and international market with several product lines. Due to its large backlog of overdue hours, a job was started in the tooling sector to make the process faster and more economical. In this context, this work has as general objective the restructuring of the critical processes of the tooling sector, aiming at a better functioning of the organization and greater satisfaction of its direct clients. In addition, this work has specific objectives, such as (1) application of high performance tools, (2) analysis and improvement of existing processes, development and application of new processes, (3) (High Speed Machining) (4) production monitoring and technical support for maintenance of new processes. Thus, after the implementation of the process improvements, it was possible to obtain a reduction of 81% in the final cost and 80.5% in the process time. In addition, with some of the new processes deployed, there was a reduction in the use of personal resources and better management of machine hour load and a significant gain in the sector response time.

Nov 22, 2018

By Detlef Ehlert

In view of the increasing level of cost pressure on the part of plant owners, optimized plant operation with top product quality and maintenance costs is indispensable. Unscheduled shutdowns with increased repair costs and production downtimes are significantly reduced by preventive maintenance and the stock-keeping of spare parts. To remain competitive in the steel market, it is important for plants owners to operate their plants with the highest possible degree of energy efficiency and at high availability in order to manufacture high-quality products. Plant Monitoring Systems make it possible to optimize the manner of production. An integrated overview of the overall process, under consideration of process stability, product quality, production costs and plant availability ensures a “transparent plant”.

Aug 16, 2017

By F. D. Rodriguez, J. Ramirez Cuellar, J. Salinas Reyes, C. Gómez-de-la Garza

The Pickling Line and Tandem Continuous Mill (PLTCM) at Ternium Pesquería Facility with a Five Stands, Six High configuration started in 2013. Manufactured by PRIMETALS, to produce steel to exposed automotive market, Turnkey project, with supervision of best practices from Nippon Steel. The main equipment that the process has are; Laser welding machine, 3 loopers, Scale Breaker, jet Pickling tanks, Inspection Station and COGNEX System Side Trimmer (flying width change), Type of Mill: UCMW(S) Carrousel, 2 Tension Reels. The principals goals are, Simulate production programs, validate materials for thin thicknesses before processing, low Re-welds, optimization use Cognex, good performance in Thickness, flatness and productivity.

Oct 1, 2019

By Andrea Pezza

The paper describes the recent new installation and start-up of the second RH (Recirculation Degasser) in Rio de Janeiro plant of thyssenkrupp CSA Siderúrgica do Atlântico. The new plant is installed as part of the existing RH, the twin solution increases the overall melt shop production in the area of quality plates especially for deep drawing grades. With this new equipment, CSA is able to increase degassed grades production with a state of art asset that has the ultimate technology in operation, safety and automation. The description of the main components parts and the operational concept gives an overview of the latest experience in RH plant engineering combined with best operational practice of world class steel producer.

Oct 30, 2017

By Alberto Tremea

The eddy current system is universally recognized as a most suitable method to point out discontinuities or modifications on the roll surface. The automation of the controls through the implementation of sophisticated equipments on the grinding machine has favoured its employment in the roll shop. A big effort is still going on to clarify the best way to promptly identify situations that could be really unsafe for the roll life. The results presented in this paper have been obtained through an intensive activity conducted in field by Innse Cilindri on work rolls of finishing stands of hot strip mills. The correct interpretation of the eddy current signals and a good calibration of the automatic system have allowed, in many cases, a substantial optimisation of regrinding practices.

Aug 16, 2017

By Detlef Ehlert

With the proven “Plug & Work” concept developed by SMS Siemag, automation systems are tested and optimized in the test field in a near-reality environment before being shipped and commissioned at a customer’s site. The process and production simulations provide scenes showing the specific mechanical equipment, the drive systems and the technology of the corresponding customer plant. Beside the technological simulation of the plant and the IO-simulation with the automation system, the production simulation is one of the three important parts of the Plug & Work simulation environment. It serves two important additional purposes: the 3D visualization of the entire customer plant on the one hand and the mapping of the logistic procedures in the plant on the other. In order to provide a close-to-reality visualization of the plant, the original design data of the individual customer plant are used for creating the visualization and prepared using an appropriate export filter. In this way, it is ensured that production sequences can be optimized in advance together with the customer, so that each customer can be trained on his own future plant.

Aug 16, 2017

By Juliano Braz Possatti, José Fagundes Júnior

This project involved a teamwork including process control, maintenance and operation specialists, R&D and CTO experts to identify and actuate on each opportunity to increase charging temperature, furnace efficiency, decrease discharging temperature when possible, decrease FM and RM cycle time (mainly speed increase and interpass time decrease), tracking zones optimization, safe use of equipment power limits, safety interlocks revision and tune models for Mill Pacing Control and Slab Design.As result of these efforts, ArcelorMittal Tubarão HSM today occupies a prominent position among the best HSM of similar layout and produced mix of the group and worldwide. This paper will show the path which was followed by the AMT HSM team to achieve more than a 20% productivity increase resulting in a hot coils production per year more than 700 million tons higher.

Oct 1, 2019

By Daniel Andrade Paes de Lima, Gerson Evaristo de Paula Júnior, Beatriz Fausta Gandra

The gradual reduction of the sinter feed size has been a complicating factor in the maintenance of sintering productivity. In addition, pellet feeds have been used for chemical correction. Because of this, it is necessary an effective cold agglomeration step in sintering to keep the ironmaking competitiveness. Thus, in the present paper, four different technological routes for cold agglomeration with sinter feeds (drum mixer, intensive mixer + drum, double drum and HPS - Hybrid Pelletized Sinter) were evaluated in pilot scale and their impacts on the indicators of the sintering and the sinter quality was obtained. It was found that the best results on granulation index and, consequently, productivity were obtained in the route using HPS. However, the sinter from this process was the most fragile among the analyzed ones. The performance of the double drum process was superior to the intensive mixer from the point of view of productivity and sinter quality.

Oct 1, 2019

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 Emanuelle Garcia Reis, Gustavo de Sousa, Rodney Pardo Alves

Gerdau Ouro Branco´s plate mill started the operation in 2016 with high level technology. In general, national and international plate markets are every day more rigorous about final product quality. Suppliers must be aware about dimensional accuracy, surface quality and flatness of the plates, independent of the quality standards. To guarantee the best service to this increasingly demanding and competitive market, it is extremely important to guarantee the original project conditions executing the right maintenance of the rolling mill main components. In order to maintain the product quality and avoid the production and maintenance cost increase, it is important to find ways to control the mill and the main process variables, through daily measurements of the equipment performance. This paper aims to present the influence of the main equipment variables that affect the mill operational stability and how to control and evaluate the mill performance.

Oct 1, 2019

By John Anthony Vasquez

During the last years Riva Acciaio Verona has taken the decision to invest in the route of a fully automated meltshop. The aim is to reduce at the minimum the operator's intervention from the bucket preparation till the ladle transfer to the continuous casting bay. The foundation for achieving the goal is the introduction of innovative technological solutions (fully automated cranes for bucket charge in the EAF, robots for sampling, etc. The paper underlines how the different solutions are based on the best practices to improve operator's safety and describes the different steps of the project, the different solutions adopted and the results in terms of production, energy savings, cost reduction and improved safety. Details are presented for: scrap yard management and bucket preparation, EAFs centralized controls and related robots for auxiliary operations (sampling, EBT cleaning, scraper for slag door automation, complete mass & energy balance based on process control), LFs centralized controls and process integration.

Aug 16, 2017

By Andrea Pezza

The steel market is experiencing a difficult conjuncture: on the one hand steel producers minimize their investments while optimizing their over- production, on the other hand suppliers reduce their internal human resources and capacity in order to overcome the instability of the new era. A return to the steel production levels of the past is not expected in the short term. Research, development and plant concept optimization is one recipe to drive the future of the steel business. This article describes a new concept for a VOD plant developed as a result of thorough investigation and assessment of all possible solutions. A joint and tight cooperation with the final customer was necessary to reaching important results. This article consists of the contributions from the plant suppliers in terms of their experience and feedback, as well as the final user’s. The final customer, voestalpine Giesserei Linz GmbH, and the plant supplier, Primetals Technologies, are both worldwide players and highly focused on reaching best quality and innovation.

Oct 30, 2017

By HaiWen Luo, Bin Hu

A ultra-high strength medium Mn steel with good ductility was designed and manufactured via the combination of warm rolling and V alloying, which produced not only the extensive precipitation of fine VC particles in both ferrite and austenite but also the bimodal size distribution of retained austenite (RA) grains. A substantial increase of yield strength up to 650 MPa was achieved due to the addition of V without deteriorating ductility. The coarse RA grains firstly transformed to martensite during yielding at the much higher stress threshold, followed by a significant work hardening due to dislocations multiplication, twinning-induced-plasticity (TWIP) and transformation-induced-plasticity (TRIP) in the ultrafine RA grains. The best combination of strength and ductility included 1.5 GPa ultimate tensile strength and 28% total elongation. This was achieved due to the sustainable TRIP and TWIP effects in the later straining stage resulting from the ultrafine austenite grains, the latter were reversely transformed from the recrystallized ferrite grains.

Oct 1, 2019

By Jackson Teixeira de Oliveira, Douglas Batista Mazzinghy, Vanderson Eney de Matos, Alexandre Camilo Leles de Figueiredo

This work studied the effect of different ball sizes in the secondary grinding stage of Samarco. The Moly-Cop Tools 3.01 spreadsheet was used for models calibration and simulations, considering grinding balls topsize of 15, 20, 25, 30 and 35mm diameters. A normal specific selection function up to the largest fed ore particle size (840μm) was obtained. The higher generation of fines and compliance with particle size specifications (+ 74μm and -44μm) proved to be more favorable for smaller ball sizes. The specific energy consumption was lower for the 15mm ball (10.7kWh/t), increasing up to the 35mm ball (13.0kWh/t). Although smaller diameter balls seem to be the best option for the size specifications, some factors may limit their use, such as: the higher generation of specific surface area; and the amount of ball purge in the discharge of the mills.

Oct 3, 2019

By João Carlos Jânio Gigolotti

O avanço tecnológico tem gerado demanda crescente por materiais que possam ser utilizados em alta temperatura e ambientes oxidantes, o que inclui ligas intermetálicas MR–Si–B (MR = metal refratário) com estruturas multifásicas. Assim, este trabalho teve por objetivo estudar a microdureza de ligas do sistema Hf–Si–B na seção isotérmica a 1600ºC, na região rica em Hf. Ligas Hf–Si–B foram fundidas com lâminas de Hf (min. 99,8%), Si (min. 99,998%) e B (min. 99,5%), em forno a arco e tratadas termicamente a 1600 ºC em atmosfera de argônio. As relações de fases nessas ligas foram identificadas por difração de raios-X e por contraste, em imagens obtidas via microscopia eletrônica de varredura no modo elétrons retroespalhados. As ligas tiveram sua dureza medida pelo método Vickers (microdureza) com cargas de 0,05 kgf e 0,2 kgf e tempo de aplicação de 20 s. Os resultados, obtidos da média aritmética das medições realizadas nas regiões heterogêneas de cada liga, mostraram uma dureza média de 11,08 GPa, com pequeno coeficiente de variação de 3,8%. Os boretos HfB2 (19,34 GPa) e HfB (11,76 GPa) apresentaram dureza mais elevada que os silicetos Hf2Si (8,57 GPa), Hf5Si3 (9,63 GPa), Hf3Si2 (11,66 GPa), Hf5Si4 (10,00 GPa), HfSi (10,02 GPa) e HfSi2 (8,61 GPa).

Aug 17, 2017

By Luiz Alberto dos Santos

Neste trabalho foram usinados CDPs da liga com composição de 50,9 % at de Ni e, em seguida, as amostras foram envelhecidas em temperaturas entre 350-550 ºC, tensões aplicadas de 60 MPa e tempos de 45 e 180 minutos. Além disso, foram realizados também envelhecimento sem aplicação de carga nas mesmas condições de temperatura e tempos para comparação das propriedades, porém acrescentando uma amostra solubilizada a 850ºC durante 1 hora. Posteriormente as amostras foram caracterizadas por DSC para determinação das temperaturas de transformação de fases. Observa-se neste trabalho que o DSC de algumas amostras apresentou tanto no aquecimento quanto no resfriamento dois picos de transformação que pode estar relacionado ao aparecimento da fase R. Além disso, pode ter ocorrido a formação da fase Ni3Ti4, pois ligas com teores acima de 50,6 %at. de Ni são caracterizados pela formação de precipitados ricos em Ni, que pode acarreta na diminuição da concentração de Ni na matriz e aumento da temperatura de transformação. Este trabalho é importante, pois há poucos estudos relacionados com o efeito do envelhecimento sob carga nas propriedades de efeito de memória de forma e superelasticidade da liga NiTi.

Aug 16, 2017

By Alberto Pesamosca

The paper presents the results obtained by the AC EAF supplied by Danieli at Kroman Çelik (Gebze-Turkey) after the planned upgrade to 150 ton. The EAF – 7,4 m diameter, based on the full platform standard design - is able to handle a maximum power of 114 MW and is equipped with the most advanced and reliable technology, including module injection system and the Hireg electrodes regulation system. Excellent results were already obtained with 120 heat size in terms of fast start-up and excellent performance figures. After the upgrade, productivity was increased up to 212 t/h, maintaining high process efficiency (365 kWh/t with 32,1 Nm3/t O2).

Jul 30, 2018

By Claudio Fabbro

The increasing demand of wire rod high carbon grades for both small and large sizes are challenging the wire rod producers to enhance new technologies by combining high plant productivity and efficiency of superior quality finished products with extreme process flexibility. The possibility to change process route according to the final application of the rolled steel grade and to simplify production planning is one of the most important keys to success that distinguishes the mill plants developed by Danieli. This paper will focus on the most important metallurgical and process targets and on the in-line heat treatment technologies representing the core of Danieli know-how on high carbon grades production.

Jul 30, 2018

By Herrmann Flor

In steelmaking process, where up to 70% of variable cost of finished product is already incurred, energy and refractory costs account for 45-50% of the cost of production of crude steel and contribute significantly to the carbon footprint of the end product. Any attempt to control and reduce these costs will automatically lead to more competiveness and reduced carbon emissions. Leading the technology for ECOPLANT (characterized by the fact that the economic and ecological benefits are integral part of our products), SMS has developed innovative solutions which can be applied to both new and existing plants alike. This paper reviews one of the electrical and automation concepts. Tackling the secondary gas cleaning system and hence being applicable to almost all steel plants, the X-Pact® Gas Cleaning Assistant optimizes the control of individual dampers based on modelling of fluid resistances of ductwork in gas cleaning system. It guarantees the best dust removal from work place at minimum energy consumption.

Oct 30, 2017

By Patrick Tassot

Increased worldwide highly competition in steel market imposes innovative measure for the steelmaker targeting cost reduction and climate-friendly steelmaking process in order to have the ability to withstand the pressure of the market. At the same time the demand for high purity and highest quality steels continues to grow from year to year, especially in the sector automotive in transportation of oil and gas, in the construction Industry and in the manufacture of heavy plate. As they allow producers to be up to the requirements while allowing expanding their product mix, new secondary metallurgical treatments have become a must additionally to standard equipment elements of steel plants modern. Most of these treatments occurs in the steel ladle increasing the pressure to ensure a reliable and as possible neutral reactor. Intelligent solutions for refractory lining ladles should integrate better adaptation to the operational process parameters and the high reliability/availability at the best cost/performance. This challenge has conducted Refratechnik to develop new concepts to overcome the frontier between shaped and unshaped materials and that’s what will be covered in this paper.

Aug 17, 2017