In the production of ferroalloys, high quality of charge materials and their careful preparation are required to ensure the normal operation of furnaces and compliance of products with customer standards. Carbon reducing agents used in this process must have high reactivity, electrical resistance, and meet strict requirements for ash, moisture, and volatile matter content. The quality of reducing agents significantly affects the technical performance of the main equipment and the metal recovery process. One of the important indicators of reducing agents is their humidity, which affects the operating mode of furnaces and their transportation. In the ferroalloy industry, fluctuations in the moisture content of the charge components can lead to changes in the thermal and electrical modes of the furnace. For example, the production of high-carbon ferrochrome requires pre-drying of reducing agents to a strictly defined humidity index. The moisture capacity and water saturation of reducing agents are important indicators for determining the temperature and drying mode. The study examines the use of brand G coals from the Zhalyn deposit for the production of special coke and mixed with brand D coals from the Shubarkol deposit in a ratio of 1:1. The purpose of the experiments was to study the moisture capacity and water saturation process of the resulting special coke in comparison with the Shubarkol special coke. The research results show that the moisture capacity of the special coke affects the optimization of production processes, improvement of operational characteristics, storage and transportation, quality control, energy efficiency and environmental safety. Therefore, researches of the moisture capacity of special coke play an important role in improving the efficiency, safety and sustainability of industrial processes.

https://doi.org/10.48081/RKRP8312

2024

Issue 2

This article presents the results of the development and methodology for the selection of rational compositions of polymer and fiber concrete, providing physical and mechanical characteristics of new structural materials for the engineering industry. The novelty of these studies is the proof of the technical feasibility and economic feasibility of obtaining a new composite material that can be used in mechanical engineering in the manufacture of equipment for the mining and metallurgical complex. At the moment, composite materials such as polymer and fiber concrete are widely used in various industries. Studies have revealed that it is rational to use a filler with intermittent granulometry consisting of three fractions. At the same time, smaller fractions fill voids in larger fractions, which increases the density of polymer concrete and its strength. The influence of the main factors on the characteristics of polymer concretes is investigated: the rotation frequency of the mixer working body, the mixing time of the components and the temperature of the resin ED. The technology of mixing the components in two stages has been developed, which ensures the production of a homogeneous mixture and an isotropic material after curing. The conducted studies have confirmed that the use of these materials for body parts in mechanical engineering is not inferior in technical characteristics to traditional materials such as cast iron and aluminum alloys. The equipment used in mining enterprises and metallurgical plants is subjected to severe operating conditions, such as exposure to aggressive media, high dust content, sudden temperature changes, transportation of abrasive liquids, etc. In this regard, in the production of machine bodies and mechanisms, it is necessary to increase their thickness, which leads to excessive metal consumption, difficulties in maintenance and an increase in cost. Replacing traditional metals with composite materials with improved characteristics seems appropriate.

https://doi.org/10.48081/MIQJ9460

2024

Issue 2

The results of laboratory experiments on the influence of temperature, reducing agent consumption and process duration on the distribution of zinc and lead between products of high-temperature burning of clinker together with calcium chloride are presented. It was found that at temperatures above 700 ° C, the zinc content in the clinker decreases sharply. The minimum zinc content in the clinker is 0.85 % achieved at a temperature of 900 °C. An increase in temperature to 1000 °C only slightly reduces the zinc content in the clinker (up to 0.77%). An increase in the consumption of CaCl2 from 1.0 to 1.3 times higher than its consumption from the SRQ increases the zinc content in the distillates from 36.23% to 40.85 %. A further increase in the consumption of CaCl2 has little effect on the zinc content in the sublimations. The optimal parameters of high-temperature burning of clinker together with calcium chloride have been established: T =900 °C, t= 60 minutes, the consumption of CaCl2 is 1.3 times higher than its consumption from SRQ. High quality zinc sublimates were obtained, % by weight: 40.87 Zn; 0.16 Pb; others. The extraction of zinc into the distillates is 99.3 %. The presence of a minimum lead content in the distillates will not significantly affect their quality. The results obtained form the basis of the final stage of the chlorinating technology for processing lead-containing zinc dust of ferrous metallurgy and are used in the construction of a common technology for the selective extraction of zinc and lead into commercial products.

https://doi.org/10.48081/WDEH9242

2024

Issue 2

The article considers one of the urgent tasks in the field of metal pressure treatment – the study of patterns of microstructure changes during the implementation of intense shear deformations during rolling in the oval-circle gauge system. To describe the evolution of the microstructure, a numerical modeling method was chosen based on the phenomenological Johnson-Mail-Avrami-Kolmogorov model (JMAK model), widely used in studies of various metal forming processes. In the DEFORM 3D software package, finite element modeling of the rolling process using the trapdicine and new schemes was performed, and the microstructure parameters for AISI 316 steel were calculated using a dynamic recrystallization model. A comparative analysis of the values and nature of the cross-sectional distribution of the average grain sizes of materials obtained by rolling according to the traditional and new scheme was carried out. Based on the modeling results, it was established that the implementation of intense shear deformation during rolling in the oval-circle gauge system provides more intense and uniform grain refinement over the entire cross-section of the strip compared to the traditional rolling scheme. Confirmation of the heterogeneity of the mechanical properties of the metal across the cross section during rolling according to the traditional scheme was obtained. The effectiveness of the new rolling scheme in working out the areas of the original billet most affected by defects has been proven.

https://doi.org/10.48081/GTRY3997

2024

Issue 2

Thermodynamic modeling was carried out using the HSC Chemistry software package to determine the optimal process parameters using a second order rotating design (Box-Hunter design). This modeling helps improve the understanding of physical and chemical processes, allows you to predict the behavior of a system under various conditions, optimize processes and reduce the time and resources required for experiments. The influence of temperature on the equilibrium distribution of silicon, manganese and aluminum in the briquette-coal-quartzite system was determined. The degree of transition of silicon and manganese into the complex alloy, as well as the content of these metals in the alloy, were determined using thermodynamic modeling. Increasing the efficiency of complex processing of raw materials in the ferroalloy industry is also facilitated by the use of prepared charge in the form of briquettes of ore and a reducing agent. We offer smelting of a complex master alloy from a briquette consisting of substandard manganese raw materials, coke screenings, as well as high-ash coal and quartzite, followed by modeling the smelting process in a laboratory ore-smelting furnace. Electric smelting was carried out using manganese-containing briquettes, high-ash coal and quartzite (to adjust the chemical composition and neutralize residual carbon) in an ore-thermal electric furnace with a capacity of up to 150 kVA. As a result of experiments on ore-thermal electric smelting of briquettes with high-ash coal, a complex master alloy with an average silicon content of 45.92–53.11%, manganese 27.72–34.81% and aluminum 5.60–6.91% was obtained.

https://doi.org/10.48081/YBOS2438

2024

Issue 2

One of the most important technological processes that determine the quality of castings is the manufacture of a casting mold. The article provides an analysis of the current state of the issue of obtaining high-quality castings in sand-resin molds (SRM). It is determined that SRM allows to produce high–quality castings with a minimum percentage of casting defects, but the disadvantage of such molds is the high cost of a binder - thermosetting resin of pulverbakelite. It is determined that one of the main directions of reducing the cost of the mold by reducing the binder content, and, consequently, the casting as a whole, is the use of pressure in the shaping process. The research is aimed at working out technological modes in the conditions of applying regulatory pressure, which make it possible to reduce the binder content in the SRM. In this regard, studies contributing to the improvement of the technological process of manufacturing sand-resin molds, in particular, providing high strength and density while reducing the content of expensive binder (pulverbakelite) in mixtures, and not degrading other parameters, are relevant. An important issue for molds is their composition. Traditionally, the main components of the molds are filler (quartz sand) and binder (one type of resin is pulverbakelite). In addition to the main components, additives are used in the study: kerosene and industrial alcohol. In studies, sanitary and hygienic standards are strictly observed in the workplace due to the release of phenol and ammonia during the destruction of resin. In total, about 20 sources were analyzed.

https://doi.org/10.48081/LYLN8169

2024

Issue 2

This project presents a three-stage ball traction drive for electric vehicles, providing a remarkable speed ratio of 1/27. The geometric and kinematic aspects were carefully analyzed and calculated manually and then verified using Recurdyn software at different rotational speeds (100, 500, 1000 rpm). To prevent ball displacement at higher rotational speeds, a strategy involving a small gap between the intermediate balls was employed. For material selection, "Gear-Steel" was favored because of its high yield strength complemented by thrust bearing integration. The static equilibrium analysis was performed manually to provide insight into the relationship between the preload forces, which were further visualized using MATLAB graphs. The rolling efficiency for each stage was calculated separately. The design involved connecting three circular flanges using 18 pins and 18 heavy hex bolts. Modeling in ANSYS revealed a maximum equivalent stress of 737 MPa in the third stage. Finally, Solidworks helped optimize the topology, resulting in a noticeable 14.5% reduction in overall volume.

https://doi.org/10.48081/AHMR1201

2024

Issue 2

This article describes the existing methods of agglomeration of ore raw materials. Their main methods and mechanisms are considered. The technologies for the formation of briquettes and brex are described in detail. In the work, finely dispersed chromium raw materials from the Kempirsai deposit were used as the materials under study. The material is a free-flowing substance obtained after drying chromium ore. The chemical and granulometric composition of finely dispersed chromium raw materials are given. The binder material is organic matter, solid and amorphous material polyacrylamide. Which is a polymer based on acrylic acid amide, odorless, powder with a particle size of less than 1 mm. A comparative analysis and differences between the methods of agglomeration were made. The procedure for carrying out agglomeration is described, and the results of laboratory studies on agglomeration are also obtained. The briquettes and brex were tested for drop, drop, impact and abrasion strength. The results of testing briquettes and brex for strength are given, which are presented on the graph. Qualitative indicators of the obtained agglomerated products and resistance to transportation and numerous transfers were evaluated. The recipe for the optimal composition of the mixture for agglomeration has been selected. The factors influencing the quality of briquettes and brex are determined. Keywords: Polyacrylamide

https://doi.org/10.48081/MGFW7056

2024

Issue 1

This article presents studies of the introduction of fluxes into the sinter mixture; the more FeO in the melt, the more magnesium in the magnetite phase lattice. In metallurgy, in the production of ferrous metals, technogenic waste is often used as cheap substitutes for iron, manganese, and chromium ores. As a rule, technogenic waste has a fractional composition of less than 5 mm. Agglomeration of alumina production waste with the production of iron ore agglomerate makes it possible to involve various man-made wastes in metallurgical processing. According to the data presented, when dolomite is used as a flux, it is confirmed by the presence of metallic iron in the iron ore agglomerate. The introduction of dolomite into the sintering charge makes it possible to produce a fluxed agglomerate. When using sinter for metal smelting, fluxed sinter will allow limestone to be removed from the furnaces. A conclusion that leads to saving a significant amount of heat spent on dissociation СаСО3 and MgСO3, fuel is saved accordingly. Magnesium dissociates with magnetite to form MgFe2O4 and MgO. To confirm the reliability of the research carried out, samples of non-fluxed and fluxed agglomerate were studied and the averaged elemental composition of the sinter was carried out according to EDS analysis, shown in the figures and tables in this work.

https://doi.org/10.48081/RPJE8094

2024

Issue 1

One of the methods of high-performance finishing turning is based on the use of peakless cutters, the cutting edge of which in the cutting plane is inclined to the axis of the workpiece, and the angle in the plan is most often zero. It is not the tip that is in contact with the workpiece, but a certain part of the cutting edge of the cutter, as a result of which turning is carried out in conditions close to the conditions of free cutting. The design of a rotary peakless rotary turning cutter with a chip breaker is devoid of one of the design disadvantages – the presence of a vertex, the weakest and most worn part of the cutting edge of conventional cutters. A constantly renewable cutting edge due to its rotation allows you to evenly distribute wear, temperature and specific loads, which significantly increases the service life of the cutting tool. Rotary peakless rotary turning cutter with a chip breaker for turning external surfaces, in the design of which a cup cutting plate is placed, mounted and rotating on an axis with bearings and due to its rotation allows the tool to provide high processing performance, increase the operating time and service life of the cutting tool due to the adjustable angle of inclination of the cutting edge – makes it possible to process various materials, and the presence of a chip breaker in the structure allows to improve the quality and reduce the roughness of the treated surface, as well as the chip formation process.

https://doi.org/10.48081/LCIP1731

2024

Issue 1