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By Chad Byron Donovan

There is a strong need in North America and other major steel producing markets where major capital investment in new equipment has been minimal over the past several years to make improvements to existing casting machines. In many cases, very cost effective improvements can be made to existing equipment in order to maximize the efficiency and production of an older designed continuous caster, a classic caster. SMS Group and its predecessor companies have been maintaining continuous casting molds for over forty years. This experience has allowed SMS Group to intimately understand the advantages and disadvantages of each design. The most vital component of the continuous caster is the mold copper design, as it has the most influence over the ability to cast a quality product. Updating to a modern copper design is less complicated than most steel producers think and the benefits are significant. Premium mold coatings such as UniGuard® and NanoGuard® allow casters to guard against exposed copper and wear while producing quality products for record campaign lengths.

Aug 16, 2017

By Chad B. Donovan

There is a strong need in North America and other major steel producing markets where major capital investment in new equipment has been minimal over the past several years to make improvements to existing casting machines. In many cases, very cost effective improvements can be made to existing equipment in order to maximize the efficiency and production of an older designed continuous caster, a classic caster. SMS Group and its predecessor companies have been maintaining continuous casting molds for over forty years. This experience has allowed SMS Group to intimately understand the advantages and disadvantages of each design. The most vital component of the continuous caster is the mold copper design, as it has the most influence over the ability to cast a quality product. Updating to a modern copper design is less complicated than most steel producers think and the benefits are significant. Premium mold coatings such as UniGuard® and NanoGuard® allow casters to guard against exposed copper and wear while producing quality products for record campaign lengths.

Oct 30, 2017

By Paulo Rodrigues dos Santos Junior, Luciano Passos de Jesus, Vagno Dordenoni Beltrame, Vinicius Antonio Ramos Pin

Faced with an increasingly demanding and selective market, a thorough analysis of each step of the processes is required in order to achieve high levels of performance. In addition to a major factor of importance in the rolling process, due to its high price, the rolls represent one of the main items in the cost of hot coils production. Using the 6 sigma methodology, there were opportunities for improvement in the grinding process, fatigue analysis, improvement in NDT in rolls, as well as means to guarantee operational stability, which allowed the reduction of roll’s consumption and consequently the cost of production.

Oct 11, 2019

By Detlef Ehlert

Energy efficiency is coming to the center of attention in the metallurgical and rolling mill industry due to increasing energy costs, limited resources and political requirements. Also, a green image and energy efficient production is a clear competitive advantage. SMS Siemag, being familiar with automation and measurement equipment, provides an energy data management system which gives transparency over the energy consumptions. All energy relevant media including electricity, gas, water, compressed air and further more can be recorded. The system is manufacturer-independent and allows the use of already installed measuring technology with the possibility of subsequent extension. So potentials for improvement can be recognized and energy savings can be estimated and proven after the implementation of the measures. Being familiar with the processes in the metallurgical and rolling plants, the system by SMS Siemag allows the assignment of the energy data to the production and plant data. Only by this connection, the data can be reduced to key performance indicators allowing authoritative evaluation of energy efficiency. The results are clearly represented on dashboards and support the continuous improvement process. The system also supports the energy controlling with an automatic reporting system, cost center assignment and in support with certification according to ISO 50001.

Jul 30, 2018

By Túlio Magno Fuzessy de Melo, Luciano Santos Marques, Vicente Tadeu Lopes Buono

The influence of the coiling temperature after hot strip rolling on the microstructure and on the tensile and hole expansion properties of a 800 MPa multiphase steel was investigated. For the temperatures between 150°C and 600°C the microstructure consisted of a ferritic matrix with a dispersion of fine martensite-austenite (MA) and regions of degenerated upper bainite. In all cases the ferrite presented a heterogeneous mixture of polygonal, quasi-polygonal and acicular grains. The yield and tensile strengths showed a tendency of decreasing with the increasing coiling temperature, probably because of the larger fraction of MA particles at lower temperatures and higher fraction of quasi-polygonal ferrite at higher temperatures. The elongation was not significantly affected by the variation of coiling temperature. The average hole expansion ratio showed a maximum of 80% for the material coiled at 400°C and fell below 50% only for the coiling temperature of 150°C, probably due to the larger hardness difference between the ferrite matrix and the MA particles.

Oct 1, 2019

By Lesli Peterson

Spraying Systems Co® has continued to develop and evolve descale nozzles through the years. The most recent addition to the descale nozzle line, the DescaleJet® Pro, provides more impact and a more uniform distribution than previous descale nozzles. The improved performance has been achieved through multiple design changes such as a smoother approach, updated vane design and improved carbide orifice. In addition to providing improved spray performance the nozzle also lasts longer than previous versions. The new technology has been thoroughly tested in the lab using impact measurements and accelerated wear testing. In addition to lab testing the nozzle has provided improved performance and longer wear life for those that have made the change to the new technology. The new nozzle technology and the benefits to the rolling mill will be discussed.

Jul 30, 2018

By Juliano Braz Possatti, Arnaldo Carneiro Salles, Cleudson dos Santos Rego, Leandro de Lucas Mendes

The increase in customer demand for steels with higher surface requirements, associated with the need to increase ArcelorMittal Tubarão's HSM productivity, it was necessary the development of controls and actions to reduce scale losses within the scenario of high productivity. This article describes the path followed by the hot strip mill team in order to reduce the occurrence and severity of scales.

Oct 10, 2019

By José Fagundes Junior, Cleudson dos Santos Rego, Bruno Bastos da Silva Murad, Vitor Borlot Borba

Since the startup in 2002, the Hot Strip Mill at ArcelorMittal Tubarão has increased gradually the coil output as the customers demand new and more resistant dimensionally challenging (thinner and/or wider) steel grades. As a critical feature for customer applications, improvements have been carried out aiming a higher thickness performance and reduction of internal losses while still meeting the more restrict tolerances booked by the customers. This paper presents the recent thickness performance evolution since 2017 and the main actions deployed to improve it.

Oct 1, 2019

By Paul Riches

Today’s steel producers face the dual challenge of ensuring on-time delivery and ever demanding product requirements, while also running a lean operation. Every day the management of a long rolling plant requires continuous optimization of both operating and business practices. Imagine a long rolling facility, where individual pieces of equipment communicate with each other, where sensor information can be used not only for control purposes but to also monitor the condition of the equipment, where models are used to verify the process is within working limits and the equipment raises alerts to operators when it requires maintenance! Utilizing the ongoing evolution in technology though data collection, communication, internet of things, control techniques and smart sensors, there is now more information available than ever before. The collection and analysis of this information will both advance control and monitoring of plant performance; revolutionizing long rolling mill plants worldwide and optimizing the entire value chain, along with improved and more flexible production.

Oct 30, 2017

By André de Cabral Oliveira

With the onset of the global economic crisis in 2008, and more precisely from 2009, production routes in iron making as blast furnace, sinter and coke oven, indicated a significant increase in frequency as well as intensity of undesirable incidents. The cost impact of such deteriorations of the production chain cause significant losses ranging up to several hundred million dollars annually. On the other hand, opportunities for processes improvement are contributing to enhance process efficiency and results, and also reduce or even avoid losses from unexpected incidents. The use of specialized services for processes has gained projection along the plants and emerged as an attractive alternative to increase results by increasing the performance and reducing costs and expenses. Process Services are formatted to achieve cooperative and customized solution during planned or urgent interventions, conducting feasibility studies, process improvement, training, among others, providing knowledge, information and crucial actions to preserve and optimize processes and plant facilities.

Aug 2, 2018

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 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 Osvaldo Guilherme Comineli

An extensive investigation into the role of low copper contents on the hot ductility of C-Mn-Al steels has been carried out in order to better understanding the problem of “hot shortness”. Previous work has suggested that this problem results from the build up of Cu that occurs at the surface of the steel as a consequence of the preferential oxidation of iron. This causes the formation of a Cu-rich film of low melting point. A nickel addition has been reported as a solution to the problem, since it increases the solubility of copper in the austenite. After hot tensile testing to failure, samples of Cu-containing steels have been examined using optical, scanning and transmission electron microscopes. Recently published results indicate that copper, in addition to precipitating out as CuS, also segregates to MnS inclusions forming a shell around them. This does not seem to impair the hot ductility under an inert atmosphere, but may have serious consequences under an oxidising environment and lead to “hot shortness”. The influence of nickel in improving the hot ductility seems to be due to it forming a higher melting point alloy with the segregated copper. Data from this incomplete work also suggests that Ni reduces the precipitation of CuS particles. Current investigation carried out using confocal microscopy still to be completed will improve the understanding of the role of copper and nickel on the problem of “hot shortness”.

Aug 8, 2018

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