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By Patrick Edward Connell

The next generation of the well-established 3-roll Reducing & Sizing Block (RSB), the RSB SCS® is the latest milestone in reducing and sizing technology for SBQ products. It offers enhanced bar quality, improved productivity, mill availability and economy as well as a simplified, safe and environmentally friendly operation. A newly developed modular drive concept of the RSB SCS® grants a smaller footprint in the layout, a reduced oil-lubrication volume and a simplified maintenance schedule. Intelligent engineering leads furthermore to reduced hydraulic functions of the RSB SCS®, which ensures a safe and environmentally friendly rolling. Another integral part of the RSB SCS® is an innovative stand changing concept, which allows automatic stand changing within three minutes. The new RSB SCS® also includes a Fast Remote Control (FRC) which enables the immediate adjustment of the roll gap against the rolling force (under load) within milliseconds. Size changes along the free-size range can also be made within the traditional billet gaps in less than five seconds. At the core of the future-oriented RSB SCS® is a real-time closed-loop control system called Size Control System (SCS®) acting with 3-roll stands adjustable under load (AUL) and / or the heavy duty stands. These features remarkably further improve the rolled tolerances and their reproducibility, and at the same time simplify the operation by means of an automated optimization of the process parameters for the rolled bars.

Aug 16, 2017

By Michael Windhager, Karl H. Ziehenberger

ULTIMA® are high performance, centrifugal cast, double poured (CC duplex) work rolls. This paper describes the principle of the ULTIMA® roll concept and its wide range of usability. The ULTIMA® concept provides a solution for rod and bar mills to increase performance and output, even under harsh rolling conditions. The main focus is on highly loaded mill stands that require both high wear resistance and resistance against thermal fatigue, like pre-dog bone, dog bone, slitter. Specific case studies of quite different mill configurations and rolled product mix prove the positive impact on production yield, mill and roll shop operations, and profitability in terms of TCO (total cost of ownership).

Oct 1, 2019

By Evan Thomas

It has been shown before that liquids can slip at a solid boundary, which prompted the idea that parallel-surface bearings can be obtained by the use of alternating slip and non-slip regions in the direction of fluid flow. The amount of slip at the wall depends upon the surface tension at the liquid - solid interface, which in turn depends on the chemical composition of the surface and its roughness. In the present study a heterogeneous surface was created by coating half of a circular glass disc with a coating repellent to glycerol. A rotating glass disc was placed at a known distance above the coated stationary surface and the gap was filled with glycerol. With the top surface moving in the direction of slip to non-slip region, a pressure build up can be theoretically predicted. The pressure gradient in the two regions is constant, similar to that in a Rayleigh step bearing, with the maximum pressure at the boundary. In order to accurately measure the force generated by the pressure increase, a load cell was attached to the heterogeneous disc. Experiments were conducted by varying both sliding speed and distance, and the resultant load carrying capacity was measured and compared with theoretical calculations. This allowed the slip coefficient of the coated surface to be evaluated.

Jul 31, 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

By Jean-Paul Simoes

The development of the blast furnace over the last years lead to a substantial increase in production capacity and productivity. This development triggered an evolution of the cooling systems in order to cope with the raising heat loads. The excellent protection of the shell by copper staves allowed blast furnace operators to achieve campaign lifetimes of more than 20 years. However in recent years some blast furnaces have experienced severe wear of the copper staves due to abrasion. The influences of the blast furnace design as well as of the operation conditions on this premature wear have been analysed and the mechanisms leading to the wear will be explained. New developments in the copper stave technology are part of the solution for avoiding premature wear during periods with less favourable conditions. The protection mechanisms made available by the new design extend the inherent protection mechanisms of copper staves to these periods. BFXpert® system is the ideal tool for the monitoring of the process data, the process models and the recommendations given by Sachem® support the operator in choosing efficient operation points. The charging with a Bell Less Top® (BLT) allows an accurate controlling of the blast furnace with regard to the optimization of the gas distribution. High performance operation together with long campaign lifetimes are thus made possible.

Aug 1, 2018

By Hervé Thomasson

Siemens VAI has made an important Research & Development effort since 10 years on laser welder field. The last step of this program was in 2010, the evolution of its laser welder range by implementing the solid state technology with laser cutting and welding. Since this step, 8 welders were produced by Siemens VAI. Now after more than 1 year of industrial feedback, the results are showing a high level of performances on very demanding processing lines for a large range of products from Silicon steel to High Strength Steel with DP and TRIP grades. This laser welder concept using laser cutting and welding through solid state laser source is also proposed by Siemens VAI for pickling lines and tandem mills with significant advantages compared to standard solution.

Jul 30, 2018

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 Jörg Schwelberger

Government regulations around the world concerning environmental care are becoming more stringent, also including regulations and restrictions of depositing and use of dust, sludge and slag generated in the iron and steelmaking process. With this scenario, by-products such as iron containing dust, sludge, oxide fines, mill scales and slag, become a valuable resource and recycling may be a profitable activity within a plant. Up to ten percent in mass of the total steel output of dust, sludge and mill scale by-product materials and more than 40% of slag by product are generated within an integrated steel plant with an iron content ranging from 50% to 65% for fines and up to 25% for BOF-slag. Slags are being widely recycled and used in the cement industry, as is the case for BF slag, and in the construction industry in the case of BOF slags and EAF slags. However, value of BOF unmodified slag is typically low and environmental regulations limit the usage of the unmodified BOF slag. This paper describes innovative solutions for recycling of fines using cold briquetting technology and the modification and granulation of slag from steelmaking that increase the value of the by-product and yield a marketable product.

Aug 16, 2017

By Christian Geerkens

Increasing requirements on slab quality initiates SMS group in developing products with a high sophisticated level regarding production and process. These characteristics are represented by SMS group’s HD family. HD stands for High Definition or the improvement of product quality via higher precision of the casting processes. A deep look inside into casting process is realized by the use of fiber optical equipped HD mold. High definition casting process control is assured using the HD spray and HD size. For objective, environmentally friendly and highly informative analyze of the inner quality of the cast products the new HD scan is present.

Aug 16, 2017

By Ian James McDonald

Each year, approximately 400 million tons of blast furnace slag is produced worldwide with a tapping temperature of around 1,500°C. It is normally used as a substitute for cement clinker or as an aggregate material in road construction. Currently, the slag is granulated in wet-granulation plants using large volumes of water and to date, it has not been possible to utilise the remnant heat energy of the molten slag, which amounts to approximately 1.8 GJ of energy per ton. However, in an R&D project currently underway led by Primetals Technolgies and industrial partners, a new dry atomising technology is being investigated to use air to cool molten slag and recover the lost heat energy. The resultant pelletised slag fulfils the same criteria as wet-granulated slag for use in the cement industry. Phase 1 of the project has now been completed where a technical plant was set up at the University of Leoben in 2012. A series of dry-slag granulation campaigns were carried out using remelted blast furnace slag. The elevated offgas temperatures and the quality of the slag product as verified by the FEhS Building Material Institute have shown the process suitability as an industrial application and the decision was taken to escalate the project from large laboratory scale to a full size pilot plant. The phase 2 development of this plant is now underway and is scheduled for installation at the site of an industrial partner in early 2016 where full slag flow will be fed directly to the plant from Blast Furnace ‘slag runners. This paper will show the development path taken to date and the planned route to our goal in 2016 of being the first to industrialise the ‘game changing’ process of dry Slag Granulation with Heat Recovery from the slag.

Aug 16, 2017

By Henara Lillian Costa

This paper aims to investigate the effects of a possible incorporation of ethanol to the lubricant during engine use on friction and lubricant film thickness, by adding small amounts of ethanol to Group I base (with and without an organic friction modifier) and to formulated oils. Film thickness was measured using ultrathin film interferometry. Friction tests were carried out using a mini-traction machine to obtain Stribeck curves. The film thickness measurements showed that in the region of low speeds, where the elastohydrodynamic film is very thin and therefore boundary lubrication may prevail, the addition of ethanol produced some boundary film, which was not present for the base oils. For the base oil with an organic friction modifier, the presence of ethanol increased the thickness of the low friction boundary film. For the formulated oil, the addition of ethanol reduced film thickness in all lubrication regimes. The friction tests showed some friction reduction due to addition of ethanol to the base oil, in particular at low speeds. For the formulated oil, the addition of ethanol reduced friction at high speeds, which was associated to a reduction in the viscosity of the lubricant, but at low speeds, the presence of ethanol reduced the formation of a boundary layer, increasing friction. For the base oil containing an organic friction modifier, the presence of ethanol increased the range of speeds for which low boundary friction occurred.

Jul 31, 2018

By Ron Webber

With the difficult economic challenges currently facing the steel industry, it is essential to perform a complete analysis when determining which rolls to purchase. A properly designed “Total Cost of Ownership” model can result in significant savings. This paper will review the costs associated with rolls in both Hot Strip and Cold Strip Mills. The multitude of factors that must be considered in performing a complete analysis for the roll purchasing process will be discussed. Models for both Hot Strip and Cold Mills will be presented. Examples where traditional analysis can lead to expensive, incorrect decisions will be presented.

Oct 30, 2017

By Marco Castenetto

Some of the most significant Danieli innovations in the field of long products are the: i) The EWR® system, through automatic continuous head-to-tail flash welding of billets at reheating furnace exit side, enables uninterrupted production of the mill for endless rolling of straight bars, wire rod and bar in coils. The process is particularly beneficial to wire rod and bar-in-coil mills as it enables production of “customized-size coils” (any coil weight according to specific Customer request) and with extra-high final coil weight, even starting from low-weight billets; ii) The Spooler process is based on twistfree winding of hot-rolled rebars into highly-compact/ultra-heavy coils featuring a unique cobble-free un-coiling capability. This enables high-speed feeding of the downstream cold-processing lines with hot-rolled spooled coils coming directly from the rolling mill without the need of any traditional off-line operation (such as de-coiling, stretching & re-winding). The system results highly beneficial both to bar-in-coil producers and to the downstream lines operators. The latest step forward is the combined application of these two systems that has made it possible for endless rolling of spooled bar in coils, enabling to cumulate the benefits of the two processes, particularly as far as transformation costs are concerned.

Aug 16, 2017

By Michaela Böberl

State of the art sinter coolers are working based on the cross flow cooling principle. Thus, only a part of the thermal energy can be used for heat recovery application. The other part of the cooling air is brought unused to the environment. Furthermore, environmental regulation regarding dust emission and intelligent usage of exergy are getting stronger. Therefore, Primetals Technologies developed sinter coolers based on the counter flow principle. The cooling air passes the sinter bed in counter-flow direction enabling a direct heat transfer from the hot sinter to the air. The exhaust gas temperature can be maximized by using the total heat of the hot sinter. Due to the possible usage of the total exhaust gas amount, diffusive dust emission is reduced to zero. Two types of counter flow coolers are in the portfolio of Primetals Technologies. One type is based on a stationary shaft, in which the hot sinter is charged. The flow of the hot sinter is in vertical direction from top to bottom, in counter direction than the cooling air. The second type is a circular hopper cooler. The hot sinter is charged on top of a moving bed. At the bottom of the bed the sinter is discharged. The cooling air flows also from the bottom to the top, following the counter flow principle. Depending on the requirements, one of the two counter flow cooler types can be chosen for optimized and efficient cooling of hot sinter..

Oct 30, 2017

By Leonardo Araújo Peruch, José Fagundes, Henrique Carneiro Pinto, Marco Túlio Costa, Nayara Coutinho, José Fabiano Martins Assunção

The objective of this project was to increase the hot charge by reducing reheating energy consumption and raising the productivity of ArceloMittal Tubarão's hot strip mill by changing the HSM’s schedule process with optimization of the relocation process of slabs after HSM’s chance with focus on slab temperature in reheating time. The project began with the revision of metallurgical rules for the relocation of materials, definition of criteria temperature setting (hot / cold), definition of restrictions of the process and review of modus operandi scheduling process. With the implementation of the process / system it is expected to achieve a 10% increase in the hot charge index in slabs reheating furnaces and increase productivity of the ArcelorMittal Tubarão hot strip mill

Oct 3, 2019

By Alain Denis, Marcelo Curtes Martins, Jeferson Rocio de Oliveira

In this work we present a study of optimization of a new inhibitor for turbulence pickling line. The efficiency of inhibition was measured and the weight of loss was evaluated in four different materials to optimize the dosage of the inhibitor. In seven months we had 8.7% of reduction in pickling losses.

Oct 1, 2019

By Rob van Opbergen, Edo Engel

The highly dynamic economic climate of recent years has tightened the operating envelope for steel producers world-wide. Steel producers continue to experience immense pressure to respond quickly to changing circumstances and the focus has shifted towards efficiency improvement and maximizing flexibility in operations. The ability to safely stop, restart and ramp-up production facilities has become essential. Establishing this level of flexibility, without sacrificing efficiency, requires sound process control, fit-for-purpose process management practices and solid know-how and experience regarding special situations in blast furnace ironmaking operations. The same business environment that demands this increased flexibility has made it increasingly difficult for steel producers to sustain sufficient knowledge about these situations. While many experienced, senior operational staff have retired, a new generation of ironmaking specialists has acquired its hands-on experience over more recent decades, during which these process situations have been much less frequent than before. Over the past 10-15 years, the requirement in the industry for external operational support during e.g. blast furnace blow–downs, salamander tapping and restarts after planned and especially unplanned stops, has become increasingly frequent. This article presents a number of these cases from a process management perspective as well as with regard to project organization and optimized cooperation between internal and external teams of experts.

Oct 1, 2019

By L. Martins Demuner, D. Burzic, V. Cunha Aranda, F. L. Lourenço, G. Romeu Trindade dos Santos, F. Ramstorfer

For many years, Dynamic Soft Reduction has been regarded as a proper method in improving internal quality of slabs. Even though processes models improved significantly over the past years, the efficiency of Soft Reduction was always limited by the discretization error, which inherently exists if segment rollers cannot be positioned individually. The recently developed SRD segment type allows for an individual roller positioning within the mushy zone by avoiding any discretization deviation from the optimal gap. This paper provides a detailed technological overview of the SRD segments as well as operational results at their very first implementation at Ternium Brazil.

Oct 1, 2019

By Osvaldo Guilherme Comineli

While the hot cracking of Cu-containing steels is a serious and widely known problem for the industry, the literature reports that copper only slightly impairs the hot-ductility measured in laboratory. A distinction is drawn between hot ductility and hot shortness and the respective cracking operating mechanism involved at the respective range of temperature. The representability of the laboratory assessment of hot cracking of Cu-containing steels by hot tensile tests compared with actual results in industrial practice is discussed. The effectiveness of the variable affecting in each cracking mechanism and respective temperature range, focused in improving the hot cracking assessment of Cu-steels and the relative importance of oxidation will also be discussed. It is concluded that the hot tensile test in argon might be a good simulation if properly interpreted and that the role of oxidation is secondary in causing hot shortness. A schematic diagram for the hot tensile test is proposed.

Oct 30, 2017

By Shanti Arangala

Several improvements were made to the single strand rod mill at Laverton to increase production, reduce maintenance and improve several aspects of product quality. With changes to the water cooling line and control system, cobbles could be significantly reduced, more consistent properties obtained and yield improved. An upgrade of the laying head enabled vibrations to be reduced and thus allowed for higher speeds on small sizes. With potential for dramatically increased pipe life, a new pipe support and laying pipe system provided for improved laying pattern on small sizes and thus more uniform cooling on the conveyor and better coil package. This paper discusses details of these equipment and control system upgrades and the resulting benefits that have been realized from the project.

Aug 16, 2017