Metallurgist (v.59, #1-2)
Innovative Water Treatment Technologies for Metallurgical Plants by S. R. Sivrikov (3-8).
Water is one of the most important components of any metallurgical production process, which is why the overwhelming majority of metallurgical plants are built near natural sources of water. In Russia, 200–220 m3 tons of water is consumed in the production of one ton of steel. To save money and resources, most metallurgical plants use circulation-type water supply systems that need to be equipped with modern systems to clean the water. The selection of an efficient, high-quality water treatment system is not a simple problem, since its successful solution is necessary for reliable and efficient operation of the main equipment used in production processes at the plant. Otherwise, scale and deposits of iron oxides are formed, corrosion takes place, and other undesirable events ensue. The modern water-treatment industry offers many different ways of solving this problem. This article describes innovative water-treatment technologies that have been developed by Amiad Water Systems in Israel based on automated filtration systems.
Keywords: water treatment; filtration; automatic self-cleaning filter; vacuum scanning; micro-fiber; disk
Three-Dimensional Mathematical (Dynamic) Model of the Sintering Process. Part II* by Yu. A. Frolov; L. I. Polotskii (9-15).
This article presents a three-dimensional mathematical (dynamic) model of the sintering process. The model was developed to solve theoretical and practical problems. It allows real-time determination of the distributions of the temperatures and the chemical compositions of the charge, the melt, the sinter cake, and the gas in the bed of charge materials with allowance for transients. The model also permits real-time determination of the temperatures in the pallets and the parameters of the gas flow (including infiltrating air) in the flue system of the sintering machine.
Keywords: mathematical three-dimensional (dynamic) model; sintering process; sintering machine; gas; moisture content; reduction; gas dynamics; evaporation; condensation; heating; oxidation; cooling; melting; filtration velocity; temperature; fuel; chemical composition; charge
Study of Heat Losses in a Blast Furnace with the Injection of Pulverized-Coal Fuel Into the Hearth by V. I. Andreev; A. V. Pozdnyakov; Yu. L. Kurbatov; I. V. Mishin; D. S. Pikalov (16-24).
Studies were made of the changes in heat loss that occur during the operation of a blast furnace with pulverized-coal fuel (PCF). It is shown that the use of PCF increases heat losses relative to the furnace's heating capacity. These losses increase from 1.15% without PCF use and an intact lining to 3.7% with maximal lining wear and the use of PCF at a rate of 187 kg/ton pig iron. Minus the chemical heat of the top gas, the heat losses incurred relative to the heating power of the furnace increase from 2.78 to 8.81%.
Keywords: blast-furnace technology; pulverized-coal fuel; heat losses; radiation; convection
XIII International Congress of Steelmakers by G. N. Elanskii; A. E. Semin; N. A. Smirnov; V. M. Parshin; L. N. Shevelev (25-43).
The XIII International Congress of Steelmakers was held October 13–16, 2014 at the Severskii Pipe Plant. The event was organized by the Association of Steelmakers inter-regional nongovernmental organization and the United Metallurgical Company. The theme of the Congress was “Steel: The Answer to the Needs of Our Times.” There were 295 participants from 85 different organizations in Russia, Belarus, Germany, Moldavia, Kazakhstan, Israel, Poland, Brazil, Rumania, the U.S., China, and Japan.
Manufacture, Study, and USE of Briquetted Ferroalloys for Steel Deoxidation by O. K. Tokovoi; V. I. Khyakkinen; A. I. Zorin; V. V. Obrezkov (44-48).
A method is developed for manufacturing briquettes based on fine ferroalloy screenings providing sufficient mechanical strength and suitability for transportation. A batch of briquettes is manufactured from ferroalloy screenings for steel deoxidation. Ferroalloy briquette composition is studied in a scanning electron microscope. It is shown that a briquette consists of fine ferroalloy particles and pure silicon bonded by sodium silicate with various additives. Ferroalloy briquettes are tested for medium-carbon steel deoxidation in a steel-pouring ladle. Silicon assimilation from ferroalloy briquettes is 65% on average.
Keywords: ferroalloy briquette; electron microscope; steel deoxidation; silicon assimilation
Behavior of the Melt When Air is Supplied Through Spatially Oriented Lances During the Melting of Electronic Scrap by A. N. Telyakov; D. V. Shmidt; T. A. Aleksandrova (49-53).
Results are presented from studies of the intensive radial injection of an air blast into a crucible to recycle electronic scrap. A relation is found to describe the effect of the blast and the unsubmerged air jet on mass transfer, and an empirical formula is obtained to calculate the unit air flow rate in the critical regime.
Keywords: melt; air flow rate; blast; electronic scrap; concentrates; silicon; melting; copper-nickel anode; lead
Effect of Liquid Melt Nitriding Method on Steel’s Nitrogen Content by I. P. Shabalov; G. A. Filippov; A. E. Semin; L. E. Shchukina (54-59).
Various methods are considered for introducing nitrogen as an alloying component into steel in order to improve a set of metal mechanical and corrosion properties subsequently. It is noted that use of a high-temperature plasma makes it possible to affect the form of nitrogen present within a gas stream (molecular, excited, atomic). The last two forms are very actively absorbed by metal, and this makes it possible to obtain its required content within metal in quite a short time. Thermodynamic calculations are performed for assimilation of different forms of nitrogen by metal. A series of laboratory experiments for nitriding alloy steel 10Kh8NMVFB confirm the results of calculations for greater nitrogen solubility with plasma-arc melting.
Keywords: special metallurgy; nitrogen steels; plasma-arc melting; critical nitrogen concentration
Effect of Accelerated Cooling Parameters on Microstructure and Hydrogen Cracking Resistance of Low-Alloy Pipe Steels by Yu. I. Matrosov; A. A. Kholodnyi; M. Yu. Matrosov; E. S. Popov; G. N. Konovalov; S. V. Sosin (60-68).
The effect of accelerated cooling parameters on microstructure and hydrogen initiated cracking (HIC) is studied for thick-walled low-alloy steels of strength categories X52–X65 used for manufacturing large diameter pipes intended for operation in hydrogen sulfide media. Optimum accelerated cooling regimes are determined providing formation of a ferrite-bainite microstructure throughout the rolled product’s thickness, exhibiting improved hydrogen cracking resistance.
Keywords: low-alloy steel; controlled rolling; accelerated cooling; microstructure; hydrogen initiated cracking (HIC); hardness; ferrite; bainite
Mechanical Tests and Construction of Analytical Models of the Behavior of Materials Under Superplastic Conditions. Part II* by E. N. Chumachenko; V. K. Portnoi; I. V. Logashina (69-75).
Different test methods are described to determine the mechanical properties of materials in the superplastic state. The flow stress depends on strain and strain rate, the structural parameter of the materials, and temperature. The rheology and mechanics of superplastic deformation are discussed. The methods have been checked for reliability and produced good results in testing titanium alloys and constructing mathematical models as part of an order submitted by the company EADS (Airbus). The information given on the test methods and the subsequent approximation of materials’ mechanical properties is of considerable interest for making reliable predictions of the deformation of materials during shaping operations.
Keywords: Mechanical properties of materials; Superplasticity; Modeling; Mechanical tests
New Developments in the Formation of Pantograph Brushes and Collectors from Carbon-Based Materials by M. N. Samodurova; L. A. Barkov; N. S. Dzhigun; Yu. S. Latfulina (76-80).
An analysis is made of existing and new designs of carbon brushes and collectors for the pantographs of trams and electric trains. Descriptions are given of a new method of making carbon brushes and a new design of pantograph collector. The new method and the new design are based on inventions of the authors of the article.
Keywords: carbon brushes; pantograph collectors; designs; manufacturing methods
Use of Condensed Soda Pulp for Soda Crystallization in Alumina Production by A. V. Perestoronin; V. M. Ronkin; A. V. Panov; A. N. Fedyaev (81-86).
Sodium carbonate crystallization is studied on an industrial test scale with supply of condensed soda pulp into the production vessel of an evaporator battery, and the effect of soda pulp supply conditions on an increase in the period between washings is determined. The size of soda crystals is compared with different Na2CO3 solid phase concentration in evaporated pulp, and evaporation battery operating parameters are determined. Further areas for changing the equipment and production scheme for alumina manufacture with the use of a soda seed in all evaporator batteries are determined.
Keywords: evaporation; sodium carbonate; washing interval; evaporator battery; test evaporator unit; seed
Study of Serov Deposit Oxidized Nickel Ore Hydrochloric Acid Leaching by O. B. Kolmachikhina; V. N. Kolmachikhin; S. S. Naboichenko (87-89).
Laboratory studies are performed for leaching oxidized nickel ore with hydrochloric acid in relation to temperature, leaching duration, and leaching acid consumption. It is revealed that the amount of hydrochloric acid dispensed has the greatest effect on metal extraction into solution. The maximum nickel extraction into solution is 88.2%.
Keywords: oxidized nickel ore; hydrochloric acid; leaching
Mechanical Properties of a High Si and Mn Steel Heat Treated by One-Step Quenching and Partitioning by Hamid Reza Ghazvinloo; Abbas Honarbakhsh-Raouf; Ali Reza Kiani Rashid (90-96).
In recent decade, there has been increasing interest in applying quenching and partitioning (Q&P) as a novel heat treatment for obtaining excellent combinations of mechanical strength and ductility in steel components. This process leads to microstructures containing martensite and carbon-enriched retained austenite in which martensite acts as a strengthening phase while retained austenite significantly contributes to the elongation due to the transformation-induced plasticity (TRIP) effect during the deformation. In this research, Q&P heat treatments in which the partitioning step is performed at a temperature equal to the quenching temperature were applied to a high Si and Mn steel, and the mechanical properties of the treated specimens were evaluated and discussed. According to the final results, considerable balances of strength and ductility were obtainable in Q&P treated specimens for application in the automotive industry such as B-pillar reinforcement, inner B-pillar, front floor side member, inner door panel, etc.
Keywords: one-step quenching and partitioning; partitioning time; mechanical properties
Risk-Assessment Practices of Companies in Ferrous Metallurgy by A. G. Butrin; Z. S. Gel’manova; D. L. Yarushin (99-103).
The author presents an original method of evaluating risks for companies in ferrous metallurgy. The method involves identifying sources of risks on the basis of parameters of the external and internal environments. It was developed to help upgrade equipment at factories and increase sales.
Keywords: risk assessment; losses; mathematical expectation of cumulative losses
Software for the Raw-Materials Management System in Blast-Furnace Smelting by N. A. Spirin; V. V. Lavrov; I. E. Kosachenko; O. P. Onorin; A. S. Istomin; A. A. Burykin; K. A. Shchipanov (104-112).
A description is presented of an information-modeling system developed to help optimize the composition of the charge materials and fluxes in sintering and blast-furnace smelting. The system is based on models that provide for end-to-end accounting of the sintering-machine and blast-furnace charges, calculate the technical-economic indices of blast-furnace smelting (coke rate, productivity) when there are changes in the blast parameters, the properties of the coke, and the composition of the iron-ore-bearing part of the charge, calculate the properties of the primary and secondary slags and the desulfurizing ability of the final slag, predict the sulfur content of the pig iron; model the gasdynamic regime during smelting, and diagnose the course of the smelting operation. The software that has been developed is designed to automate the work station of production personnel in the blast-furnace shop at the Magnitogorsk Metallurgical Combine.
Keywords: blast-furnace smelting; mathematical modeling; smelting parameters; iron-ore-bearing raw materials
Finite-Element Modeling of Plate-Rolling by A. A. Bogatov; D. Sh. Nukhov; K. P. P’yankov (113-118).
Results are presented from calculation of the geometry of the deformation zone and the kinematics of plate-rolling. The results were obtained using the program packages DEFORM-3D and Q-FORM. A comparative analysis is made of the data based on the length of the lag and advance zones and the character of the nonuniformity of the stress and strain states during the rolling of plates. The criterion chosen to characterize the nonuniformity of strain inside the deformation zone is the coefficient of variation S/Λav, where Λav is the average shear strain over the height of the plate and S is the standard deviation. The stress state was evaluated on the basis of the stress-state index σ/T. A mathematical model of the plate-rolling process was constructed with allowance for the range of steels rolled on the 5000 mill at the Magnitogorsk Metallurgical Combine and the technological capabilities of the mill's equipment.
Keywords: longitudinal rolling of plates; cast structure; hot-rolled plate; fineness of the structure; mathematical modeling; stress and strain states; indices of the stress state; degree of deformation in shear; coefficient of variation; axial and contact regions of the deformation zone; lateral spread of the metal
Controlling the Composition of the Metal in the Direct Reduction of Dust-Sized Materials and Waste Products in a Jet-Emulsion Reactor by V. P. Tsymbal; S. P. Mochalov; K. M. Shakirov (119-125).
Use of the theory of self-organization has made it possible to deviate from the entrenched ways of thinking that led to the creation of traditional metallurgy's unwieldy many-pronged structure and to invent a new technology that has advantages over the established processes used in international metallurgy. Thanks to the development of a flow-rate controller (a reactor-oscillator), complete isolation of the process from the atmosphere, high pressure, internal transport, and bottom-feeding of the working mixture into a vertical column reactor, it has become possible to create dissipative dynamic structures (zones) inside the reactor and independently control oxidation and reduction reactions in these zones. All this has sharply increased the rates of the rates of the physicochemical processes that take place and decreased the volume of the unit (by a factor of 10), cut capital expenditures (by a factor of 2–3), and reduced energy consumption.
Keywords: control; direct reduction; self-organization; dissipative structures; zones; reactor-oscillator; column reactor
Cooling of the Anode Gases of Aluminum Reduction Cells in Alumina-Heating Heat Exchangers by S. G. Shakhrai; V. V. Kondrat’ev; A. V. Belyanin; V. N. Nikolaev; V. A. Gron (126-130).
An analysis is made of the amount of heat lost in heating alumina to the temperature of the melt after it is charged into the reduction cell. Also analyzed are the amount of electric power consumed to make up for this loss and the amount of heat that the anode gases carry off into the gas exhaust system. A technical solution is proposed to reduce the amount of energy consumed by reduction cells with a self-baking anode. The solution entails using the heat of the anode gases to heat the alumina, which makes it possible to reduce unit electric-power consumption by 135–170 kWh/ton Al.
Keywords: reduction cell with self-baking anode and upper current lead (VSS) ; heating of alumina ; heat of anode gases ; recovery
On the Efficiency of Oxygen Enrichment of the Blast and the Use of High Top-Gas Pressure as Means of Intensifying Blast-Furnace Smelting by G. V. Korshikov; V. N. Titov; V. G. Mikhailov (131-140).
This article discusses the main mechanisms by which the oxygen content of the blast and high gas pressure affect the smelting rate in a blast furnace. It is shown that oxygen enrichment of the blast – just as an increase in gas pressure in the furnace – is a means of intensifying the smelting operation. Oxygen enrichment of the blast accomplishes this by reducing the quantity of gases flowing inside the furnace.
Keywords: oxygen; pressure; intensity; coke rate; productivity; unit output of hearth gases
Features of Bivalent and Trivalent Iron Oxide Reduction from Slag with Carbon by S. A. Makeev; A. K. Zaitsev; V. S. Valavin; Yu. V. Pokhvisnev (141-148).
Liquid-phase reduction of bi- (FeO) and trivalent (Fe2O3) iron from slag with activated coal is studied: BAU (wood) and KAD (bituminous). Kinetic relationships are obtained for reduction at 1450°C from slag with an initial overall iron content Fetot ≈ 5%. It is shown that regardless of the type of coal liquid-phase reduction of iron to metal from slag with a preponderance of Fe2O3 is difficult compared with slag containing mainly FeO, and requires preliminary reduction of trivalent to bivalent iron. A relationship is established for the rate of liquid-phase reduction on carbon reducing agent properties (structure porosity, ash content, sulfur content). The greater reducing capacity of BAU coal compared with KAD correlates with the lower ash and sulfur content of BAU coal.
Keywords: liquid-phase reduction; bi- and trivalent iron; activated coal; thermodynamic modeling; Romelt technology
Trends in Technologies for the Production of Quality Steels by S. V. Tyutyunik; A. A. Klachkov (149-151).
The 13th International Congress of Steelmakers was held at the end of 2014 in Polevskoy (Sverdlovsk Oblast) at the Severskii Pipe Plant (STZ), which is part of the Pipe Metallurgical Company (TMK).
Development of Optimum Billet Cooling Temperature and Rate Regimes for CBCM Conditions at the Dneprovskii Metallurgical Combine by A. V. Gress; O. A. Chebotareva (152-155).
A calculation procedure is proposed for optimum billet cooling temperature and rate regimes by finding a multicriterion global extremum. Calculated results are provided with respect to a specific CBCM.
Keywords: CBCM; temperature and rate regimes; stresses; liquation; global optimum
Comparative Analysis of the Use of Different Types of Dies to Draw Tubes by R. A. Okulov; S. V. Parshin (156-158).
A study was made of the effect of different types of drawing dies on the geometry of faceted tubes. The object of study was a process for mandrel-free cold drawing of hexagonal tubes made of carbon steel 20. The study was performed on a computer by means of finite-element analysis.
Keywords: steel 20; drawing; faceted tube; die tool
Use of Lubricants on a Stretch Leveller for Steel Strip by A. P. Dolmatov; P. P. Dolgikh; M. A. Usachev; V. D. Shipilov (159-163).
To reduce the adhesion of contaminants to the straightening rollers of a machine designed to straighten cold-rolled steel strip that has been annealed and undergone temper rolling, it has been proposed that the rollers of the stretch leveler be sprayed from above and below with a 5.0–6.0% solution of process lubricant Volgol-355. A series of measures has been implemented to optimize the conditions under which the solution is delivered and solution residues are removed from the strip's surface. This has eliminated the formation of streaks of contaminants on the surface, reduced the number of "scratches" and "dents" formed on it, improved the surface finish of the straightened rolled product, and made it possible to begin cutting the strip and shipping it to complete customers' orders. The deviation of the strip from planarity is no greater than 2 mm/lin. m.
Keywords: stretch leveler; non-planarity; process lubricant Volgol-355; degree of contamination based on the reflection coefficient
Detection of Metallurgical and Production Defects in Engineering Components Using Metal Magnetic Memory by A. A. Dubov (164-167).
The main sources of damage during engineering component operation are local stress concentration zones (SCZ) that form under action of operating loads, and primarily at defects of metallurgical and production operation origin. The size of these SCZ is from several tens of micrometers to several millimetres. However, where these local zones are located and how it is possible to detect them are unknown. The non-destructive monitoring (ultrasound, x-ray, MFD, and others) quality control standards used in manufacturing plants considerably exceed the dimensions of metallurgical defects. A fundamentally new non-destructive monitoring (NM) method is more widespread in practice, based on use of metal magnetic memory (MMM). It is based on the natural magnetization developed during component manufacture. Possibilities of the MMM method are considered during diagnosis of metallurgical and production defects in new components.
Keywords: engineering component; non-destructive monitoring (NM); diagnosis; metal magnetic memory (MMM) method; ultrasonic monitoring (UM); magnetization; stress concentration zones (SCZ); defect
The Rate of Lead Sulfide Distillation from Polymetal Concentrate and Polymetal Matte Prepared from it by G. V. Skopov; K. V. Bulatov; D. Yu. Skopin (168-176).
A probabilistic-deterministic planning method for an experiment under laboratory conditions in a neutral atmosphere is used to determine lead sulfide distillation rate for a copper-lead-zinc concentrate of the composition, %: Cu 12.57, Pb 19.86, Zn 12.93, Fe 17.62, S 29.43 and matte prepared from it, %: Cu 19.33, Pb 12.85, Zn 9.76, Fe 30.95, S 22.50. At 1100°C the lead sulfide distillation rate from concentrate was six times higher than for matte; 10.1·10−4 kg/(m2·sec) against 1.69·10−4 kg/(m2·sec). In experiments the values of distillation process activation energy from concentrate in the range 800–1100°C and from matte in the range 1000–1200°C are close and correspondingly 119.6 and 102.1 kJ/mole. The dynamic transfer of lead sulfide activity within matte determined by the method was 0.05 which points to strong bonding of zinc sulfide with matte components.
Keywords: concentrate; matte; zinc sulfide; distillation; rate; activity
Autoclave Leaching of Arsenic from Copper Concentrate and Matte by V. I. Neustroev; K. A. Karimov; S. S. Naboichenko; A. A. Kovyazin (177-179).
Results are given for autoclave leaching of concentrates and mattes from polymetal semiproduct melts containing arsenic alongside copper. The possibility is demonstrated of selective copper and arsenic leaching into solution. It is confirmed that with autoclave leaching arsenides are broken down better than for natural arsenic-containing minerals.
Keywords: leaching; matte; concentrate; copper; arsenic