Defending the “Peace of Sunday”: The Debate over Sunday Labor in the West German Steel Industry after the Second World War

Working hours were largely unregulated in nineteenth-century Germany, but a powerful alliance emerged in the 1890s between the Christian churches and the socialist labor movement to prohibit most industrial labor on Sunday, including most production of steel. In the 1950s steel management persuaded organized labor that it would be advantageous to produce steel continuously throughout the week, the prevalent system in other countries. The Evangelical Church retreated in this debate, but the Catholic Church waged a fierce and partly successful campaign from 1952 to 1961 to defend the old prohibition. Until the 1980s organized labor continued to cooperate with both major churches to keep Sunday industrial labor quite rare. Their influence declined suddenly after national reunification in 1990, however, and many Germans have come to prize individual freedom above the old principle, honored by Christians and the unchurched alike, that most people should have the same day of rest.

Methods to optimize energy consumption in Conarc furnaces

Over the past few decades, steelmaking has reached its zenith in terms of annual productivity, and relevant processes have been developed over time to produce steel with maximum efficiency in a shorter time. One of the prominent steelmaking practices used extensively in contemporary industries is the Conarc Steelmaking Practice, which involves the use of electrical and chemical Energy to carry out melting and decarburization in respective shells. This article reviews the factors that affect the energy consumption in Conarc furnaces and provides insight into the technologies developed to alleviate energy consumption and make the steelmaking process optimal in terms of energy consumption and requirement. This article also accentuates relevant systems and melting practices for the raw materials, which can be utilized in the Conarc Steelmaking practice to make the entire process less energy-intensive. Oxygen-enhanced combustion and thermophotovoltaic systems can alleviate energy consumption substantially while maintaining steel quality at the same time, as discussed in the paper. Additionally, some mathematical models have been discussed that facilitate in formulating an energy optimal and financial steelmaking process.

Iron ore market report 2019–2020

Preliminary figures of global iron ore and steel production in 2020 show a slight decline. The article reviews iron ore production by global companies (Vale, Rio Tinto, BHP, FMG, Anglo American, etc.) in 2019 and 2020, as well as production figures by the leading steel producing countries (China, India, Japan, Russia, USA, South Korea) in 2020. Iron ore imports and exports are also analyzed. It is noted that the global iron ore exports had increased by around 43% over the previous decade, however, they went down by 1.7% in 2019, and this decline in exports continued in 2020. Australia is the largest iron ore exporter with a market share of 55%; this share increased by one percentage point in 2020 compared to the previous year. Green-field projects by global producing companies are presented in Brazil, Australia and other countries. A conclusion is made that despite a 3.5% decline in the global economy forecast by the International Monetary Fund in 2020, it is possible to acknowledge that the iron ore market is well balanced. However, if steel demand and steel production volumes increase unexpectedly and some of the planned new mines are not commissioned, the surplus can quite promptly turn into a deficit. In the long term, the plans to produce steel without using fossil fuels, without coke and therefore without CO2 emissions, could revolutionize the iron ore market and increase the demand for products with a high iron content. Источник: https://mining-media.ru/en/articles/original-paper/16396-iron-ore-market-report-2019-2020

Investigation of CGHAZ Simulations of Low-Carbon Bainitic Steels

The effect of ten different combinations with various amounts of niobium (0-0.6 wt.%) and chromium (1-4 wt.%) on weldability and mechanical properties of thermomechanically rolled and direct-quenched low-carbon (0.035 wt.%) microalloyed bainitic steel were investigated. Two compositions were alloyed with boron to increase the hardenability, and two with titanium to improve the toughness properties in heat affected zone. The target of the study was to produce steel with 700 MPa yield strength combined with good impact toughness. Coarse grained heat affected zone (CGHAZ) simulations were performed using the Gleeble 3800 thermomechanical simulator to evaluate the weldability of the investigated steels using cooling time from 800 °C to 500 °C (t8/5) of 5 s and 15 s to simulate different heat inputs in actual welding procedure. Microstructures were characterized using light optical microscopy, and hardness profiles of simulated heat affected zones were determined as well as Charpy-V impact toughness at-40 °C and-60 °C. Shorter t8/5 time (5 s) produced generally better impact toughness properties compared to longer t8/5 -time (15 s). Steels with 4 % Cr had the highest impact energies. Generally, more softening occurred with longer t8/5-time (15 s). However, Cr and Nb alloying decreased the amount of softening in the CGHAZ region, especially with longer t8/5 -time. These results indicate that even with higher t8/5 -time, it is possible to achieve strength properties equivalent to the base material in the CGHAZ region by Cr and Nb alloying.

Preliminary Study on the Capability of the Novel Near Solidus Forming (NSF) Technology to Manufacture Complex Steel Components

The benefits of the novel Near Solidus Forming (NSF) process has shown previously in its ability to produce steel components with comparable as-forged mechanical properties but with a cost reduction of 10–15%. This study further pushes the NSF technology to produce parts that are conventionally difficult to produce via conventional methods. A 2.7 kg 42CrMo4 steel grade component was manufactured into a complex geometry using only a 400t press. Different manufacturing parameters were evaluated to show their influence on the process and final component. A combination of X-ray fluorescence (XRF), optical microscopy and SEM analysis of the microstructure was also conducted revealing the deformation pattern of the material and shedding some light on how the material evolves during the process. The successful forging of these components shows the capability to produce previously deemed difficult geometries, with much a lower specification forging press, in a single deformation.

Near Net Shape Casting: Is It Possible to Cast Too Thin?

With increased efforts across the steel industry to produce steel in more economical ways, interest in near net shape casting has increased. Although much has been reported on the production of exotic alloys via these methods, to make the investment in new casting equipment, capability to produce current high value steels by these methods would derisk the capital expenditure. This study assesses the production of a dual phase steel (DP800) by belt casting and compared to that of conventional continuous casting. Although a drop in yield and tensile strength was seen in the belt cast-produced material, the increased elongation allowed for a comparable/improved UTS × elongation factor. A combination of in situ dendrite measurements, thermal modeling, and lab-scale belt casting has allowed insight into the relationship between cast thickness and final band spacing. The inherent lack of deformation of near net shape casting results in coarser band spacing and is not accounted for by the refinement of the secondary arm spacing caused by the faster solidification rates. This limits the strength achievable for a given martensite volume fraction. This has been predicted across the full range of casting thicknesses (1 to 230 mm) and good agreement has been shown with experimental results.

Hydrogen Ironmaking: How It Works

A new route for making steel from iron ore based on the use of hydrogen to reduce iron oxides is presented, detailed and analyzed. The main advantage of this steelmaking route is the dramatic reduction (90% off) in CO2 emissions compared to those of the current standard blast-furnace route. The first process of the route is the production of hydrogen by water electrolysis using CO2-lean electricity. The challenge is to achieve massive production of H2 in acceptable economic conditions. The second process is the direct reduction of iron ore in a shaft furnace operated with hydrogen only. The third process is the melting of the carbon-free direct reduced iron in an electric arc furnace to produce steel. From mathematical modeling of the direct reduction furnace, we show that complete metallization can be achieved in a reactor smaller than the current shaft furnaces that use syngas made from natural gas. The reduction processes at the scale of the ore pellets are described and modeled using a specific structural kinetic pellet model. Finally, the differences between the reduction by hydrogen and by carbon monoxide are discussed, from the grain scale to the reactor scale. Regarding the kinetics, reduction with hydrogen is definitely faster. Several research and development and innovation projects have very recently been launched that should confirm the viability and performance of this breakthrough and environmentally friendly ironmaking process.

Dynamic Modeling and Simulation of Basic Oxygen Furnace (BOF) Operation

Basic oxygen furnaces (BOFs) are widely used to produce steel from hot metal. The process typically has limited automation which leads to sub-optimal operation. Economically optimal operation can be potentially achieved by using a dynamic optimization framework to provide operators the best combination of input trajectories. In this paper, a first-principles based dynamic model for the BOF that can be used within the dynamic optimization routine is described. The model extends a previous work by incorporating a model for slag formation and energy balances. In this new version of the mathematical model, the submodel for the decarburization in the emulsion zone is also modified to account for recent findings, and an algebraic equation for the calculation of the calcium oxide saturation in slag is developed. The dynamic model is then used to simulate the operation of two distinct furnaces. It was found that the prediction accuracy of the developed model is significantly superior to its predecessor and the number of process variables that it is able to predict is also higher.

Effect of Steel Cord Tension During the Lapping on Steel Cord Straightness After Lapping

One of the variable parameters in steel cord twisting technologies is the steel cord tension before final reel. Changing this parameter is used to produce steel cord with high quality of straightness. Steel cord straightness is the most important technological parameter after tensile strength. It is simple to change the value of steel cord tension with special mechanisms or devices in composition of cable machines and twisting machines. It is very important to know the measures of tension setting. Low tension causes bad quality of steel cord and defects. High tension may brake steel cord during the twisting and lapping. Also high tension may change the mechanical properties of steel wire in the steel cord construction. The influence of steel cord tension in the range from 9 N to 30 N on active equivalent stresses in wire cross section and macro displacements of wire contact points in steel cord construction was shown. Effect of steel cord tension during the lapping on steel cord straightness after lapping was shown. In this research the optimal tension for producing steel cord 2x0.30HT was defined with numerical simulation, finite element analysis and criteria method. The optimal value of tension for other steel cord constructions will change, because of number of wires and its hardness.

Raw Materialism and Socioeconomic Change in the Coal Industry

In the midst of activist, citizen, and policymaker concerns about and advocacy for the end of coal as a fuel, this chapter takes a long-term historical-materialist perspective on energy and society relations. The historical evolution of coal commodity chains from mines in global peripheries to consumption in world-system cores through four periods of attempted and real hegemonic ascent (British, US, Japanese, and Chinese) are addressed. This analysis from the nineteenth century to 2015 demonstrates that generative sectors based on coal helped drive economic ascent in all four of these cases. Further, coal remains critical for aspiring powers, notably China and India, to produce steel and electricity. China’s and India’s combined coal consumption drove a near doubling of global hard coal production between 2000 and 2015, despite declining coal use in the OECD countries. The medium-term future of coal is therefore far from certain, despite environmental costs and concerns.