scholarly journals Influence of the mechanical characteristics of harp screen material on screening process

2018 ◽  
Vol 61 (9) ◽  
pp. 678-682 ◽  
Author(s):  
A. D. Bardovskii ◽  
A. A. Gerasimova ◽  
A. M. Keropyan ◽  
P. Ya. Bibikow
Keyword(s):  
Mechanical Characteristics ◽  
Raw Materials ◽  
Frequency Range ◽  
Lateral Separation ◽  
Technological Parameters ◽  
Steel Cable ◽  
Screening Process ◽  
Clay Particles ◽  
Steel Cables ◽  
Technical And Economic Indicators

The paper presents the results of studies on the influence of mechanical characteristics of harp screen material on the technological  parameters of screening. A mathematical model of the vibrational  process of harp screens is presented depending on the length of their  free areas, magnitude of technological load and characteristics of the screened material. Dependences of the relative vibrations amplitudes  of rubber and cable strips on the length of their free areas are determined for different values of process load. As a result of the researches, it was established that the amplitude of the relative vibration of  rubber strip under load decreases with increasing length of their free  areas and for steel cable strips it increases, reaching a maximum at  certain values of process load. It was also found that presence of the  load dramatically reduces the amplitude of relative vibration of rubber  strips, especially, in the area of dimensionless frequencies of the order of (0.6  –  1.4)g, while the vibrations amplitude of cable strips vary  slightly in this frequency range. The article presents information on  rubber-cable harp screening surfaces of mesh type: strips in the form  of steel cables, rubberized with rubber cover having lateral separation  projections. The use of rubber-cable strips as working elements of the  screening surface allows to increase the “open area” of the screen due  to the increase of distance between supports while maintaining high  and stable amplitude of strips vibrations. Optimization of mechanical characteristics of the working elements material of harp screens and  conditions of their fixation allows to intensify separation of screened  material into fractions by eliminating sticking of the screened surface  with clay particles and clogging of the material with “difficult” grains, and to improve significantly technical and economic indicators of the  screening process. Such screening surface passed successful industrial tests at a number of quarries producing construction aggregates for the separation of crushed stone and gravel. Economic efficiency of the rubber-cable harp screens is presented in comparison with the wire screens in technological schemes of processing of mineral raw materials.

scholarly journals Smelting options for carbon ferrochrome based on ore raw materials, middlings and their technological evaluation

2022 ◽  
Vol 320 (1) ◽  
pp. 51-59
Author(s):  
S. Baisanov ◽  
◽  
Ye.Zh. Shabanov ◽  
K.V. Grigorovich ◽  
R.T. Toleukadyr ◽  
...  
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Main Idea ◽  
Economic Indicators ◽  
Processing Plant ◽  
Technological Parameters ◽  
Gas Cleaning ◽  
Carbon Ferrochrome ◽  
Technological Evaluation ◽  
Technical And Economic Indicators

The article presents the results of large-scale laboratory tests carried out in the conditions of the Chemical and Metallurgical Institute named after V.I. Zh. Abishev on the use of briquetted mono-charge in the smelting of carbon ferrochrome on a 250 kVA furnace. The purpose of these studies was to determine the technological parameters of the use of briquetted mono-charge containing in its composition chrome ore, wastes from the production of high-carbon ferrochrome, middlings and various carbonaceous reducing agents. The main idea of using these briquettes was to multiply the contact surface of the reductant and ore, which should speed up the technological process. The principal possibility of smelting a standard alloy using briquetted mono-charge is shown. The alloy for individual charge options meets the requirements of the standards. In comparison with the technology without the use of briquettes, the mono-charge technology has shown advantages in all main parameters. The technology with the use of briquettes from the dust of the AktZF gas cleaning system is distinguished by a low yield of non-standard metal and slag, the bulk of the material goes into the gas collection system. Technologies from briquettes from fines pellet production area of Donskoy ore mining and processing plant and flash have very low specific technical and economic indicators and cannot be recommended for industrial use. Improvement of briquetting modes and technology of their smelting is required. The technical and economic indicators were higher than the current one, showed briquettes from ore and coke of the People's Republic of China, briquettes of ore from borlin and shubarkol coals of Kazakhstan.

scholarly journals RESEARCH OF DRYING PROPERTIES OF CERAMIC MASS IN THE SYSTEM «LOESSLIKE LOAM - ASH OF EKIBASTUZ HPP”

2020 ◽  
Vol 3 (77) ◽  
pp. 126-133
Author(s):  
S. A. MONTAYEV, ◽  
◽  
A. B. SHINGUZHIYEVA, ◽  
K. ZH. DOSOV, ◽  
B. T. SHAKESHEV , ◽  
...  
Keyword(s):  
Mechanical Characteristics ◽  
Raw Materials ◽  
Control Sample ◽  
Sensitivity Coefficient ◽  
Plastic State ◽  
Drying Process ◽  
Technological Parameters ◽  
Ceramic Mass ◽  
Drying Properties

The article investigates the drying properties of ceramic mass in the system “loesslike loam - ash of Ekibastuz HPP”. Ceramdor obtained from pure loam was selected as a control sample. A change in the structural and mechanical characteristics of ceramic masses during the drying process is associated with a change in temperature and moisture content of the material. The following results were obtained: molding moisture indicators, ductility numbers decrease with increasing ash. According to the classification of clay raw materials by plasticity, loam from a moderately plastic state goes into the category of low-plastic raw materials. With an increase in ash content of up to 20%, the sensitivity coefficient to drying leads to an increase in the time of crack appearance on the samples. A slight decrease in strength indicators is observed from 5.4 to 4.5 MPa. Thus, the results serve as the basis for the development of technological parameters in order to obtain ceramdor.

Effect of Technological Parameters of Raw Materials on the Physical-Mechanical Characteristics of Ceramics

2016 ◽  
Vol 73 (5-6) ◽  
pp. 213-218
Author(s):  
N. P. Uglev ◽  
V. Z. Poilov ◽  
V. V. Karmanov ◽  
K. S. Merzlyakov ◽  
V. L. Zvezdin ◽  
...  
Keyword(s):  
Mechanical Characteristics ◽  
Raw Materials ◽  
Technological Parameters

A possibility of using nickel concentrate, obtained as a result of hydrometallurgical enrichment of manganese-containing raw materials, at steel alloying

2020 ◽  
Vol 76 (7) ◽  
pp. 709-715
Author(s):  
O. Yu. Kichigina
Keyword(s):  
Raw Materials ◽  
Experimental Studies ◽  
Selective Extraction ◽  
Technological Parameters ◽  
Nickel Iron ◽  
Nickel Recovery ◽  
Nickel Concentrate ◽  
Steel Alloying ◽  
High Degree ◽  
Comprehensive Processing

At production of stainless steel expensive alloying elements, containing nickel, are used. To decrease the steel cost, substitution of nickel during steel alloying process by its oxides is an actual task. Results of analysis of thermodynamic and experimental studies of nickel reducing from its oxide presented, as well as methods of nickel oxide obtaining at manganese bearing complex raw materials enrichment and practice of its application during steel alloying. Technology of comprehensive processing of complex manganese-containing raw materials considered, including leaching and selective extraction out of the solution valuable components: manganese, nickel, iron, cobalt and copper. Based on theoretical and experiment studies, a possibility of substitution of metal nickel by concentrates, obtained as a result of hydrometallurgical enrichment, was confirmed. Optimal technological parameters, ensuring high degree of nickel recovery out of the initial raw materials were determined. It was established, that for direct steel alloying it is reasonable to add into the charge pellets, consisting of nickel concentrate and coke fines, that enables to reach the through nickel recovery at a level of 90%. The proposed method of alloying steel by nickel gives a possibility to decrease considerably steel cost at the expense of application of nickel concentrate, obtained out of tails of hydrometallurgical enrichment of manganese-bearing raw materials, which is much cheaper comparing with the metal nickel.

Comparative assessment of rubber steel cables for vertical mine hoists

2020 ◽  
pp. 85-93
Author(s):  
V. E. Perekutnev ◽  
V. V. Zotov
Keyword(s):  
Feasibility Study ◽  
Carrying Capacity ◽  
Load Distribution ◽  
Comparative Assessment ◽  
Life Extension ◽  
Steel Cable ◽  
Motion Stability ◽  
Cable Length ◽  
Steel Cables ◽  
Mine Hoist

Operation of inhaul rubber steel cables in vertical mine hoisting is discussed. The research in the field of mine hoisting is reviewed, and the further R&D directions are identified. Some studies concern life extension of hoisting ropes. One of the promising trends seems to be application of belt pullers as inhaul cables, which can essentially enhance mine hoist efficiency. In the meanwhile, capabilities of rubber steel cables suffer from deficient attention. The performance capabilities of rubber steel cables of top manufacturers (Promkanat and SAG) are compared, and application ranges in vertical mine hoisting are determined for such cables. It is found that the Polish manufacturer’s rubber steel cables offer a wider range of application. The analysis shows that rubber steel cables can be used as inhaul cables of vertical mine hoisters. Rubber steel cables possess suitable characteristics and are capable to elevate considerable loads to various hoisting heights. In particular, the existing rubber steel cables ensure carrying capacity of hoists up to 20-25 t at the hoisting heights to 400-500 m and sometimes can elevate skips with tonnage of 10 t to a height up to 1000 m and more. The further feasibility study of operation of inhaul steel rubber cables in hoisting units should address motion stability of a puller on a driving drum, load distribution in ropes of base of rubber steel cables, validation of hoister design, adjustability of rubber steel cable length during its operation, etc.

scholarly journals Electromagnetic Interference Shielding and Physical-Mechanical Characteristics of Rubber Composites Filled with Manganese-Zinc Ferrite and Carbon Black

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 616
Author(s):  
Ján Kruželák ◽  
Andrea Kvasničáková ◽  
Klaudia Hložeková ◽  
Rastislav Dosoudil ◽  
Marek Gořalík ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
Zinc Ferrite ◽  
Mechanical Characteristics ◽  
Hybrid Composites ◽  
Rubber Matrix ◽  
Butadiene Rubber ◽  
Frequency Range ◽  
Manganese Zinc ◽  
Manganese Zinc Ferrite

In the present work, composite materials were prepared by incorporation of manganese-zinc ferrite, carbon black and combination of ferrite and carbon black into acrylonitrile-butadiene rubber (NBR). For cross-linking of composites, standard sulfur-based curing system was applied. The main goal was to investigate the influence of the fillers on the physical-mechanical properties of composites. Then, the electromagnetic absorption shielding ability was investigated in the frequency range 1 MHz–3 GHz. The results revealed that composites filled with ferrite provide sufficient absorption shielding performance in the tested frequency range. On the other hand, ferrite behaves as an inactive filler and deteriorates the physical-mechanical characteristics of composites. Carbon black reinforces the rubber matrix and contributes to the improvement of physical-mechanical properties. However, composites filled with carbon black are not able to absorb electromagnetic radiation in the given frequency range. Finally, the combination of carbon black and ferrite resulted in the modification of both physical-mechanical characteristics and absorption shielding ability of hybrid composites.

Effects of Annealing Temperature on Morphology and Dielectric Property of BiFeO3 Films

2012 ◽  
Vol 512-515 ◽  
pp. 1736-1739
Author(s):  
Li Li Zhang ◽  
Guo Qiang Tan ◽  
Meng Cheng ◽  
Hui Jun Ren ◽  
Ao Xia
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Dielectric Property ◽  
Annealing Temperature ◽  
Raw Materials ◽  
Sol Gel ◽  
Frequency Range ◽  
Annealing Temperatures ◽  
Pure Phase ◽  
Lower Loss

Fe(NO3)3•9H2O and Bi(NO3)3•5H2O were used as raw materials. BiFeO3 thin films were prepared by sol-gel method. The effects of annealing temperatures on the morphology and dielectric property of the thin films were studied. XRD results show that the multi-crystal thin films with pure phase are obtained when annealed at 500°C and 550°C. But annealing at 580°C will lead to the appearance of Bi2.46Fe5O12 phase.AFM images show that as the increase of annealing temperatures the surface toughness of the thin film is decreased, but the surface undulation of the thin films is decreased gradually. Within the frequency range of 1KHz~1MHz, the dielectric constant of BiFeO3 thin films is kept over 125 and it does not change very much from 500°C to 580°C. Annealed at 550°C, the BiFeO3 thin films with the lower loss are obtained. At 1MHz, the dielectric loss is 0.12.

DETERMINATION OF TECHNOLOGICAL PARAMETERS OF CULINARY PRODUCTS PRODUCTION USING MIXTURES AND EMULSIONS FOR ADDITIVE TECHNOLOGIES

2020 ◽  
pp. 189-198
Author(s):  
A. Meliaschenya ◽  
I. Kaltovich ◽  
G. Pinchuk
Keyword(s):  
Broiler Chicken ◽  
Raw Materials ◽  
Chicken Meat ◽  
Additive Technologies ◽  
Technological Parameters ◽  
Optimal Length ◽  
Layer Width ◽  
Degree Of Hydration ◽  
Rational Sequence

The article presents the results of research on the determination of rational technological parameters for the production of culinary products using dry mixtures and emulsions based on animal raw materials for additive technologies. It was found that when making products using mixtures and emulsions based on broiler chicken meat, as well as a combination of broiler chicken meat and pork, pork and beef (ratio 1:1) rational height of the layer, which makes it possible to ensure stability and safety of the product shape (with a fixed diameter of the opening of the culinary syringe – 7 mm and the optimal length of the layer - 100 mm), is from 14–21 mm (with a layer width of 7 mm) and up to 133–154 mm (with a layer width of 98 mm), which allows for improved structural and mechanical (SSL – 1090.7–1099.9 Pa) and functional and technological indicators of these products (WHC – 92.7–97.5%). The rational sequence of application and the duration of chopping of the main and auxiliary raw materials for the manufacture of emulsions, the duration of preparation (3 minutes), the degree of hydration (1:2 – 1:3) and the temperature of water for the reduction of dry mixtures (60±1° C) were established, which made it possible to develop technological schemes for the production of culinary products using additive technologies.

RATIONAL PROCESS PARAMETERS OF CHOPPED SEMI-FINISHED PRODUCTS PRODUCTION USING EMULSIONS FROM COLLAGENCONTAINING RAW MATERIALS

2020 ◽  
pp. 199-213
Author(s):  
I. Kaltovich
Keyword(s):  
Heat Treatment ◽  
Weight Loss ◽  
Connective Tissue ◽  
Raw Materials ◽  
Steam Treatment ◽  
Point System ◽  
Technological Parameters ◽  
Genus Lactobacillus ◽  
Rational Process

The article presents the results of research on the determination of rational technological parameters for the production of chopped semi-products using emulsions from collagen-containing raw materials fermented by bacteria of the genus Lactobacillus. Water dosages are installed in the composition of chopped semi-finished products: 12% – with emulsions from pork skin and tails and 11% - with emulsion from connective tissue. Duration of ingredients mixing (5 minutes), sequence of raw materials laying during manufacture of articles, as well as duration of heat treatment of chopped semiproducts is determined: 25 minutes – during steaming (t = 95–100 °С), 20 minutes – during baking (t = 180 °C), 15 minutes – during frying (t = 110 °C), while recommended methods of bringing semifinished products to culinary readiness are steam treatment and baking, which allow for improved functional and technological (TUS – 79.3-81.8%, weight loss during heat treatment – 5.1–7.9%), structural and mechanical (PNS - 1413.9–1470.4 Pa) and organoleptic indicators (juiciness, appearance, consistency, taste, smell) of these products (9 points according to the 9-point system).

scholarly journals Use of Industrial Waste for the Optimization of Ceramic Construction Materials

2020 ◽  
Author(s):  
Carlos Galhano ◽  
Pedro Lamas ◽  
Diogo Seixas
Keyword(s):  
Industrial Waste ◽  
Mechanical Characteristics ◽  
Raw Materials ◽  
Bottom Ash ◽  
Construction Materials ◽  
Fine Fraction ◽  
Mineral Resources ◽  
Ceramic Materials ◽  
High Production Rate ◽  
Marble Powder

The massive growth of the ceramic industry and the consequent demand for construction materials worldwide has motivated the search for alternative solutions aimed at reducing the use of mineral / natural resources as the main source of raw materials. One of the strategies frequently adopted by the scientific community is the reuse of industrial waste. It is beneficial not only to reduce the overexploitation of mineral resources but also to reduce the environmental, economic and social impacts resulting from their incorrect disposal/treatment and consequent deposition on land unsuitable or that purpose. Duetoconsiderationssuchasphysico-mechanical characteristics and the high production rate, two different types of industrial waste were selected for this work, ashes resulting from the burning of coal in thermoelectric power plant, commonly known as bottom ash (B), and the Marble Powder (MP). It was intended to test the technological feasibility of the manufacture of ceramic materials produced from clay mixtures containing these two residues. For this purpose, the fine fraction(<63μm)obtained from the sieving of the marbleresidue(MR)and slag(Bf)was used,aswellasacoarsergrainslagfractionrangingfrom63-125μm(Bg). The resulting test samples were subjected to a firing of 950 °C under an oxidizing atmosphere, following a primary drying process. Faced with the standard values, the new ceramic materials obtained from MP have seen their mechanical and porous characteristics decrease and increase, respectively. Atthesametime,althoughtheadditionofBinno way influenced the mechanical characteristics,a significant improvement the porous characteristic was observed. The incorporation of these residues produced a color very close to the original sample material. Keywords: industrial waste, ceramic, construction materials, bottom ash, Marble Powder

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