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By Gerhard Finstermann, Ichiro Maeno, Takehiko Saito, Hironori Shimogama, Konrad Krimpelstätter

Automobile manufacturers are developing Electrified Vehicles with light steel body structure designs that reduce mass and therefore greenhouse gas emissions over the vehicle’s entire life cycle. This raises the demand for the production and development of Advanced and Ultra High-Strength Steels (AHSS / UHSS) and Electrical Steels with increased permeability and reduced core loss to improve energy conversion efficiency. To meet this requirements the steel market is tending towards new generations of AHSS with improved formability (3rd generation AHSS) and high-silicon steels with higher strength and thinner products. With this growing demand for advanced high-strength steels and electrical steels, producers are faced with a unique and interesting challenge in producing materials that strain or exceed the capabilities of existing mill equipment and automation designed to produce low- to medium-carbon sheet. While specialty steel producers have known for decades how to process special high-strength steels and thinner gauges, this equipment typically does not offer the yield and productivity desired by the market, necessitating innovation in re-engineering existing equipment to meet the market demands more economically than new construction. In the case of cold rolling, this can be supported through variable roll geometries, more effective roll-gap lubrication technologies, application of strip heaters (Warm Rolling) to reduce risk for edge crack propagation and strip breaks as well as continuous rolling managed by state-of-the-art automation technologies.

Oct 1, 2019

By Gigliola Salerno

The carbon-epoxy composite has high specific resistance and strength, which means specific applications. However, its behavior under compressive stress could be decreased by delamination, needing more detailed studies. The main purpose of the present work is to verify the mechanical properties in bending process considering two different fiber orientations. The composite materials were made by woven fibers and epoxy resin. Primarily, the carbon fiber fabrics suffered a superficial physical treatment called silanization, in order to developing a better chemical adhesion between fibers and resin. After the superficial treatment, the layers were embedded with epoxy resin. The composite resin’s cure was made in a Fanem heater, model 320, during 1 hour at 120°C at 1.5 bar; subsequently the specimens were cut by water jet. Specimens oriented in 0°/90° and 0°/90°/45 were manufactured and taken to bending tests, accordingly to the ASTM E855 and D790 standards, in an universal testing machine MTS – Material Test System, full capacity of 250 kN. It was concluded that all specimens failed by tension. Specimens with internal void volumes results in lower flexural modulus and those with presence of fracture mechanisms, like delamination, showed lower strength values. Scanning Electronic Microscopy demonstrated the damages involved during bending process.

Oct 30, 2017

By José Aparecido Pereira

The customer asked for a 5” angle roll pass design. For this angle, in a normal pass design, a 160mm billet is required. For the production of this billet would be necessary a new 160mm mold for the Continuous Casting Machine, which produces 150mm billets, increasing the complexity of the melt shop. The rolling mill is designed to produce angles up to 4", technical information recommended the replacement of a gearbox because this process would generate torque up to 15% above nominal. An innovative roll pass design was done using 150mm billet using the Aparecido-W Method that cause a higher spread in the first three passes, thus reaching the desired leg length. As this method is not used in any other known rolling mill, a FES (Finite Element Simulation) and FEM (Finite Element Modeling) was done by a Research & Development center which demonstrated that the design was viable. From July, 2018, three tests were done being produced around 700 t of good quality products without difficulty of set up. The rolling mill team carried out this project at a very low cost and in record time of five months. The average torque of the motors was 36%, without overload for the equipment.

Oct 1, 2019

By Darina Manova

Plasma assisted surface modification methods have been used to nitride stainless steels in order to enhance hardness and therefore the lifetime of industrial components. Nevertheless, the corrosion resistance is not always preserved since it is very sensitive to the process parameters, either in implantation or in thermochemical diffusion techniques. AISI 316L stainless steel was plasma nitrided using three different techniques: Low Energy Ion Implantation (LEII), Plasma Immersion Implantation (PI3) and conventional DC pulsed plasma nitriding (DCPN). For each method several parameters were tested and some of them were selected to achieve the so called S phase of about 3 µm thickness and no nitrides precipitation. The nitrided layer was characterized with OM and SEM. Hardness was assessed on the surface with Vickers indenter and 25 g load. XRD was performed to characterize the S phase and to detect other phases if present and electrochemical corrosion tests were carried out in 3.5% NaCl solution. Although the S phase thickness in the three groups of samples was comparable, hardness was not and neither was the corrosion resistance. The PI3 samples were the hardest with the best performance in corrosion experiments, resulting in a higher breakdown potential and lower currents.

Aug 8, 2018

By Peter Grawenhof

In steel mills universal joint shafts, slipper spindles and gear spindles are used to overcome the design- and process- related offset between the axis of the motors and the work rolls. At the roll side the available space for the couplings is limited by the minimum work roll diameter. This leads to extremely high loaded components of the universal couplings especially at the roll side joints. Furthermore modern steel mills continuously strive to roll larger plates and materials with increased strength. This requires drive solutions with even higher torque capacity. For these applications conventional design joints are not sufficient anymore. Even alternative solutions such as hybrid- or offset- designs fall short. Therefore the companies Voith and BUMA Engineering developed together the new GearLink drive concept in close cooperation with the Voestalpine Grobblech GmbH. A completely new combination of universal joints and gear couplings offers an up to now unique solution enabling the use of 1,35- times bigger joint with a 2,5- times higher torque capacity and a 20- times longer lifetime. The GearLink system was first time successfully taken into operation at Voestalpine Grobblech in December 2013 and is up to now working without issue.

Aug 16, 2017

By Andrea Donadon

This article introduces the Danieli Total Asset Management System, which involves 360 degrees service methods and equipment. Danieli Condition Monitoring System and Danieli Torque Monitoring System are fundamental to evaluate the conditions of the working components in heavy duty transmissions. The first one monitors the vibrations and the lubrication fluid conditions with the purpose to identify the presence of malfunctions, by detecting any variation of the signals from the standard values. The second one monitors the transmitted torque for each spindle and gearbox, with the aim of detecting any anomaly in torque distribution and magnitude, and evaluating the residual life of the mechanical parts, on the base of a dedicated fatigue damage algorithm. All these features are useful in avoiding serious damages to machines, facilities and people, but allow also planning the maintenance and overhaul activities with efficiency, in order to achieve the best plant availability and reliability. The data analysis is made by the IntelliCMS software, which interfaces with plant and Danieli operators and includes the possibility to cooperate by remote connections, simplifying service activities and support. All these features allow providing new full service programs, where the client is totally supported in maintenance, overhauls and substitutions. This is the best way to ensure the most efficient, high quality and reliable after sales assistance.

Aug 16, 2017

By Patrick E. Connell

During the ABM Conference of 2015 the latest design and process features of the new 3-roll RSB® generation were presented together with a unique Size Control System SCS® for a real time closed loop control to produce an extraordinary quality SBQ – day in, day out. In the past two years, Kocks has focused on improving the repeatability of the rolling process and developed technology to enhance the performance of its equipment. These developments include Fast Remote Control (FRC), Stands Adjustable Under Load (AUL) implementation of closed loop Size Control System (SCS), and finally a state of the art laser Gauge (4D Eagle) that pulls all of these developments into a complete package of quality. Gauges used in the past generally operated with the “shadow” measuring system. The latest gauge developments are based on the “light section” method. This method is more suitable to provide real time measurement parameters of the rolled bar. Placed close to the last rolling stand, the “light section” gauge is capable of measuring around the complete diameter with a clear definition of the bar stage in relation to the axes of the rolls. It is also capable of making these measurements using a very high measurement frequency. Following requirements of the market, requiring the highest gauge measuring frequencies which display the bar in the most accurate way even at the highest rolling speeds, the “4D Eagle” gauge was developed. This paper describes all the process features and parameters of this impressive and unique newly developed gauge as well as the other described technical improvements.

Oct 30, 2017

By Bernhard Hiebl

Global trends that are constantly challenging the iron and steel producers are related to worsening of the iron ore grades, higher substitution rates of main iron ores to cheaper raw materials due to economic pressure and increased environmental standards. Changing the raw materials in an operating plant can significantly influence the sintering or pelletizing process. Adjusting all process parameters to regain stable and high productive operation takes considerable time and causes production losses. Furthermore changes in raw materials lead to variations in the process gas flows and emission concentrations.Therefore SVAI developed two models for numerical simulation of sintering process and pelletizing process. Amongst others the models are based on Ergun equation and include chemical reactions of the related process. For already operating plants the simulations shall predict changes of the process parameters when raw materials are exchanged or when operational parameters are varied. Furthermore the simulations give advantageous information for the design of green field plants and allow the simulation of different plant configurations.The objective of this paper is to demonstrate what the latest developments are in these numerical simulations and what Siemens VAI is doing to overcome the remaining challenges in this field.

Aug 2, 2018

By Li Shanqing, Xu Jianghua, Li Hongmei, Huang Peijie

Cold rolled high strength steel are playing a very important role in reducing automobile weight for energy saving and environment protection. In recent year, more and more high strength steel were manufacturing in steel company. But there are some problems in the cold rolling process for high strength steel products. Periodic thickness deviation especially in strip head or tail is an important one in these problems. In this paper, the reason of periodic thickness deviation was analysed and a new AGC algorithm called Property FFC for high strength steel in tandem cold rolling was developed. The application of this new algorithm shows that it can reduce the thickness deviation.

Oct 1, 2019

By Elham Kordzadeh

As the world’s reserves of coarse and high-grade iron ores continue to shrink, beneficiation is becoming increasingly important. The resulting concentrates cannot be used directly as feedstock for iron making, but require an additional agglomeration step. Pelletizing is preferred, because the uniform chemical, physical, and metallurgical characteristics of pellets make them a more desirable feed for the iron making processes. The heat hardening or induration of pellets is typically done in shaft furnaces, grate-kiln systems or on straight grates. Rotary kilns were originally developed in the late 19th century for Portland cement production [1]. The main development work for the successful adaptation of the process to the thermal treatment (induration) of green balls from iron ore was performed by Allis Chalmers in Milwaukee, Wisconsin, USA in the 1960’s [2].The straight grate process, which was first used in 1955 at Silver Bay, Minnesota, was a dedicated development with the aim to pelletize and indurate magnetite (taconite) concentrate [2]. There are various important technical and economical distinctions between the two pelletizing technologies. The most important differences include that a grate-kiln has three distinct pieces of equipment, a preheat grate, a rotary kiln and an annular cooler, whereas in the case of a straight grate, the entire indurating process is done on one piece of equipment only. In addition, both technological solutions have differences in their recuperation systems, direction of air flow in drying, number of burners, form of pellet movement, etc., which cause differences in raw material suitability, process control, economical aspects, plant operation and product pellet quality.

Oct 30, 2017

By Ruediger Holz, Tommaso Settimo, Luciano Vignolo

Optimized CAPEX, OPEX, new products, yield and product quality in new process equipment as well as by upgrading of existing facilities are the key factors for success and profitable operation. For this, innovation in processes and design is crucial. Danieli can support their clients by offering innovative and well-thought-out process equipment and upgrade solutions. In 2018, Danieli has put into operation a complete cold processing complex in Turkey, which includes a new continuous pickling tandem mill featuring latest generation of market oriented technologies. In this line, dedicated to run a broad range of size and grades (IF to AHSS as DP1000), the highly efficient Turboflow® pickling process was selected. This technology already proved its efficiency and ability in former applications handling ultra-thin gauges at speeds even exceeding 400 m/min in the pickling tanks. The 5-stand 6-high OSRT tandem mill features important developments, like actuators to improve significantly strip flatness and a special air knife arrangement on the tandem mill exit side to generate perfect strip surface cleanliness. In galvanizing lines, the zinc pot is the most effective area to reduce costs in operation and consumables and increase the product quality. Danieli has spent significant efforts in developing most advanced technology for the wiping process. A fully integrated system solution has been designed to perform a wiping process with high quality, economy, accuracy and productivity. Center part is the newly developed X-Jet / Compact X-Jet air knife, added by new generation electromagnetic stabilizer as well as robotic systems to reduce human intervention and health risks in this area. This technological package is ideal also for upgrade of existing lines, typically generating a return of investment less than 1 year. On top, Danieli has developed advanced automation systems including L2 and L1 controls to achieve outstanding product performances.

Oct 1, 2019

By Marcus Weldon

We are at the beginning of an era of profound transformation and human progress — a new industrial revolution. This “Automation of Everything” era will be brought about by digital interfaces, data analysis and control of the physical world through networks employing the Nokia Bell Labs Future X1 architecture — networks to support the digitization and connection of everything and everyone with the goal of automating much of life. The interconnection of robots, machines, drones, sensors, processing platforms and people through Future X networks will provide transformative tools for the automation and optimization of factories and warehouses, ports, electric grids, transportation networks, food, healthcare, construction, logistics and supply chain, emergency response, mining, and other physical industries. To date, the level of automation has been modest at best. Automating these physical industries — industries that account for 70 percent of the US Gross Domestic Product, for example — has the potential to drive significant increases in the world’s economic productivity.2 Realizing the potential of this next industrial revolution will require billions of wirelessly connected endpoints for high fidelity physical-to-digital conversion, millisecond response times to tightly control and coordinate machines and robots, and intelligent analysis to optimize real-time decisions — tasks beyond the reach of current networks. Increased levels of automation are already being achieved through the use of 4G advanced wireless access technologies. The untethering of sensors and actuators in industrial environments through the low-latency, high-bandwidth, high-reliability, and massive scale provided by 5G wireless access will complete this evolution, providing an unprecedented ability to digitize, analyze, comprehend and manipulate the physical world at a scale never previously thought possible. These new capabilities will enable us to create digital models of the physical world with ever higher levels of fidelity, further enhancing our ability to improve operational efficiencies and increase productivity and worker safety. Doing this will require a dramatic evolution in network architecture toward massively distributed cloud control and baseband capacity to achieve the required ultra-low latency and ultra-high bandwidth for industrial and infrastructure automation services — the Future X architecture. In early 2019, Nokia Bell Labs will publish a sequel to “The Future X Network: A Bell Labs Perspective”. “Future X for Industries: A Nokia Bell Labs Perspective” will explore how the Future X architecture will automate many of the world’s physical industries, including chapters devoted to electric power, cities, rail, mining, public safety, manufacturing, ports, logistics and supply chain, and an overarching chapter devoted to securing this highly automated world. To give you a small taste of the feast that’s to come, we’re sharing with you an initial installment — “Future X for Industries: Mining” — the Nokia Bell Labs view of how mining will be transformed through a Future X architecture..

Oct 1, 2019

By Bernardo Siqueira

This paper presents a unique stirred milling technology, Outotec HIGmill™, a modern, flexible and energy efficient grinding solution for fine and ultra fine grinding being tested in an industrial scale level. The test was performed at an iron ore pellet producing plant in Sweden (for confidentiality reasons, it will be referred to only as “the client”) where a pilot HIGmill™ unit (HIG25) was installed parallel to a conventional regrind circuit to compare its performance to the existing ball mill. By using a continuous test run procedure and evaluating the parameters of F80, P80, mill shaft rotation speed and power drawn it was determined its grinding capabilities, operational flexibility and energy efficiency. Outotec HIGmill™ outperformed the existing ball mill in the plant proving its capabilities to grinding finer, with steeper particle size distribution (PSD) and much higher energy efficiency. The tests performed showed that, with further refining of its operation, it is capable of consistently deliver the required PSD with up to 30% higher grinding efficiency.

Aug 16, 2017

By Antonio Adel dos Santos, Carmos Antonio Gandra, Fabricio Mazola da Silva Paiva, Vicente Tadeu Lopes Buono

Abstract Usiminas Steel Plant in Ipatinga installed an accelerated cooling device named CLC (Continuous On-Line Control) in 2010, enabling it to supply steels produced by TMCP (Thermo Mechanical Control Process) technology. This technology complements the TMCR (Thermo Mechanical Control Rolling), with the inclusion of the accelerated cooling process after controlled rolling. There are various gains in terms of quality and productivity associated to the application of such technology. However, the flatness control for API steel becomes crucial because large thermal stresses may be generated due to thermal heterogeneity during the fast cooling when the austenite phase decomposes mostly into ferrite and bainite. In literature, there is lack of knowledge regarding a full understanding of the relation among cooling conditions and plate flatness. Therefore, this work has focused on the effect of the cooling strategy for API steels, aiming at optimizing flatness and keeping the mechanical properties within the specified ranges. The starting point was dilatometer simulation, where cooling conditions such as start cooling temperature, SCT, finish rolling temperature, FRT, and cooling rate, CR, were changed in order to evaluate their effect on microstructure. Those laboratory conditions supposed to give the best results were transposed to industrial scale, so as to produce experimental lots of plates with five different cooling strategies. It was shown the possibility to find a cooling profile that guarantees the balance between mechanical properties and flatness requirements. The influence of cooling strategy on flatness was explained by the varied heat transfer regimes occurring from hot steel surface to the ambient

Oct 1, 2019

By Jose M. Rodriguez-Ibabe, Beatriz Pereda, Beatriz Lopez, Felipe Bastos

The modeling of austenite evolution during the hot rolling of steels is covered in the literature for a wide range of chemical compositions, although mainly for carbon contents below 0.20%. In addition, most research on this topic is oriented for processes that are characteristic of flat products. Compared to those processes, the hot rolling of bars for structural applications presents considerable particularities concerning mainly deformation, rolling speed and rolling temperature profile. Those particularities result in considerable changes on process parameters that affect the austenite microstructure evolution, both in the softening and hardening mechanisms if microalloying elements such as Nb is present. The aim of this work was to develop a model to predict the evolution of austenite microstructure that is suitable for the hot rolling of structural reinforcing bars. Different torsion tests simulating industrial schedules particular from those type of processes were performed. The tests showed the need to investigate Nb strain-induced precipitation interaction with softening mechanisms that can occur during the deformation schedule. At the end, the new proposed kinetics and routines were introduced to a program, MicroSim-Bars®, that is able to model austenite evolution under structural bar hot rolling conditions.

Oct 1, 2019

By Daniel Stickel

Current political, economic and ecological guidelines demand the increase of power densities of nearly all machinery parts today. In order to further lower the wear rate towards the ultra-mild sliding wear regime an integral approach is needed, which has to regard contact conditions, surface topography, surface chemistry, as well as sub-surface properties. Still there are no simple parameters to classify the performance of tribosystem. In this study the area and volume affected by tribocontacts are calculated by means of a three dimensional elastic-ideal plastic contact model. The surfaces are generated by means of conventional machining procedures and characterized by scanning white light interferometry. The further input data as to normal and friction forces are derived by ultra-mild sliding wear tests under boundary lubrication conditions of carburized steel against carburized steel and 52100 steel against case-hardened spheroidal cast iron. This contribution will depict the distinct influence of the topography on friction and ultra-mild sliding wear of common Fe-base materials and point on the marked importance of highly localized effects, which govern the acting mechanisms.

Jul 31, 2018

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 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 Luca Tommasi

Danieli complemented its wide range of production plants for the iron and steel industry with a further step upstream into iron ore pelletizing and beneficiation. Danieli has engineered and constructed a state of the art and fully automated pilot plant facility – pot grate and sinter box – at Altos Hornos de Mexico S.A. (AHMSA) Pelletizing Plant, Monclova, Mexico. Installation and commissioning were completed in October 2009. Key features of the pot grate include the avoidance of the need for operator intervention during the test, automatic system preheat, absence of dead time, heat recuperation system with an air/air heat exchanger, oxygen control in preheating and firing with zirconia oxygen analyzer, possibility to test deep beds up to 625 mm. A series of projects have been accomplished by AHMSA availing of the pot grate facility with the aim to enhance pellet plant productivity and to reduce operating costs. The results obtained by use of Danieli pot grate combined with the experience and skill of plant operators has shown significant technical and economical benefits thus fully justifying the initial investment made by AHMSA and confirming the importance of having an in-house testing facility in order to optimize industrial plant operations.

Aug 16, 2017

By Lucia Vieira

Kelvin probe force microscopy (KPFM) can be used to monitor electrostatic charges on the surfaces of materials. In this paper, we describe the use of KPFM to evaluate the electrostatic effect induced by silver nanoparticles incorporated as clusters in diamond-like carbon (DLC) films, before and after scratching. The results are compared to those obtained for DLC films without silver nanoparticles. Raman spectroscopy was used to identify the DLC signature, and energy dispersive X-ray spectroscopy (EDX) was used to confirm the presence of silver in the film. The morphology of the DLC film containing silver was investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The findings suggest that the incorporation of silver nanoparticles in amorphous materials could offer new options for electrostatic energy storage on the surfaces of these materials.

Jul 31, 2018